International Journal of Environment and Climate Change

Floating Treatment Wetlands for Emerging Contaminants in Wastewater: A Critical Review of Removal Mechanisms, Performance and Sustainability

2026-09-21T11:31:18+00:00

Floating treatment wetlands (FTWs) are buoyant, vegetated treatment systems in which plant roots and associated biofilms develop directly within the water column. They are increasingly presented as low-energy, modular nature-based technologies for polishing wastewater and contaminated surface waters, yet their capacity to manage emerging contaminants remains less certain than their performance for nutrients, suspended solids and some conventional pollutants. This critical narrative review evaluates evidence for removal of pharmaceuticals and personal care products, antibiotics, pesticides, per- and polyfluoroalkyl substances, endocrine-active compounds and microplastics, while examining the mechanisms and sustainability trade-offs that determine whether apparent removal represents transformation, retention or simple transfer between environmental compartments. Literature from 2010 to 18 July 2026 was synthesised alongside selected earlier methodological and foundational studies. The evidence indicates that contaminant behaviour is strongly compound-specific and governed by hydrophobicity, ionisation, persistence, plant traits, rhizosphere activity, hydraulic residence time, biofilm maturity and water chemistry. Mesocosm studies demonstrate substantial attenuation of some pharmaceuticals, endocrine-active compounds and pesticides, but persistent compounds such as carbamazepine and perfluoroalkyl acids are less consistently removed. PFAS studies show that plant uptake, sedimentation and sorption can attenuate aqueous concentrations without destroying terminal PFAS, creating a requirement for biomass and sediment management. Antibiotic studies show that bioaugmentation can increase parent-compound removal, but commonly use concentrations far above those found in receiving waters and provide little evidence on antibiotic-resistance genes. Microplastic evidence introduces a further sustainability concern because floating polymer components can become contaminant sources. Hybridisation with sorbents, immobilised microorganisms or bioelectrochemical systems can improve treatment, but also increases material, maintenance and end-of-life burdens. The field therefore requires mass-balance designs, transformation-product analysis, environmentally realistic exposures, long-term field validation and lifecycle-aware performance metrics before FTWs can be regarded as broadly reliable treatment barriers for emerging contaminants.

Allelopathy in Sustainable Weed Management: From Chemical Interference to Field-scale Integration

2026-09-21T14:18:49+00:00

Allelopathy has long been proposed as a biological route to reduce reliance on synthetic herbicides, yet the agricultural evidence is more conditional than the frequency of laboratory phytotoxicity reports suggests. This critical narrative review evaluates allelopathy as a component of sustainable weed management by integrating evidence on allelochemical production, release and fate; crop–weed interference; breeding and phenotyping; cover crops and residues; plant extracts and natural-product herbicide discovery; and field-scale implementation. Literature was considered through 6 July 2026, with emphasis on peer-reviewed studies that linked biological effects to plausible chemical mechanisms and agronomic outcomes. The evidence is strongest for well-characterised chemical systems such as momilactones in rice, sorgoleone in sorghum, and benzoxazinoids in rye and wheat. Even in these systems, however, chemically mediated inhibition in the rhizosphere is difficult to separate from resource competition, canopy effects, residue-mediated physical suppression and microbial transformation. Field studies of weed-suppressive cultivars and cover crops demonstrate practically useful suppression, but they often establish an interference phenotype rather than allelopathic causality. Plant extracts and formulated allelochemicals provide credible leads for reduced-herbicide programmes and bioherbicide development, although dose realism, stability, selectivity, formulation, non-target effects and economic performance remain major translational constraints. The most defensible role for allelopathy is therefore not as a universal replacement for herbicides but as one ecological and biochemical hurdle within diversified integrated weed management. Future progress depends on field experiments that combine genetic contrasts, chemical quantification, spatial rhizosphere measurements, competition controls, microbiome-aware fate analysis and multi-environment agronomic validation. Such evidence would allow allelopathy to move from recurrent proof-of-concept towards reproducible, selective and economically credible weed-management functions.

Plant Biostimulants and Crop Yield and Quality under Climate Change: A Critical Review of Mechanisms, Field Evidence and Translational Constraints

2026-09-23T11:26:35+00:00

Climate change is reducing the stability of crop production through more frequent drought, heat, salinity and combined stresses, while rising atmospheric carbon dioxide threatens the nutritional quality of staple crops. Plant biostimulants, defined by their capacity to improve nutrient use efficiency, abiotic stress tolerance, quality traits or nutrient availability independently of their nutrient content, are increasingly promoted as adaptation tools. The evidence underpinning these claims is extensive but fragmented across controlled-environment physiology, product-specific field trials, meta-analyses of heterogeneous studies and a small number of multi-site agronomic networks. This critical narrative review evaluates how far the available evidence supports the use of plant biostimulants to protect or enhance crop yield and quality under climate-related stress. Peer-reviewed literature published between January 2014 and July 2026 was identified through searches of agricultural, biomedical and multidisciplinary scholarly indexes, supplemented by citation tracking and institutional sources, and was appraised thematically with attention to study design, scale, heterogeneity and conflicts of evidence. The synthesis indicates that mechanistic plausibility is well established for several categories, particularly seaweed extracts, protein hydrolysates, humic substances and beneficial microorganisms, which modulate hormonal signalling, water relations, osmotic adjustment, antioxidant capacity and root function. Quantitative syntheses consistently report mean yield gains in the mid-teens, with larger responses in arid environments, degraded or nutrient-poor soils and low-yielding systems. These averages conceal very high heterogeneity, and large regional field networks have reported negligible or modest responses for some commercial products. Quality responses are frequently positive for antioxidants, vitamins and micronutrients but can involve trade-offs such as nitrate accumulation. Inconsistent product composition, poor viability of some microbial inoculants, limited reporting of stress intensity, publication bias, geographical concentration and scarce multi-season data substantially constrain confidence. Evidence concerning combined stresses, elevated carbon dioxide, waterlogging and long-term soil effects remains particularly thin. Plant biostimulants are best regarded as context-dependent complements to breeding, water management and nutrient stewardship rather than as generic climate solutions. Standardised stress-explicit field protocols, independent multi-environment testing, product characterisation and integrated yield-quality-economic assessment are required before strong adaptation claims can be justified.

Carbon Sequestration in Agricultural Soils through Agronomic Management: Mechanisms, Evidence, Accounting Boundaries and Research Priorities

2026-09-24T09:36:59+00:00

Agricultural soils have lost substantial organic carbon through land conversion, intensive cultivation and insufficient organic inputs, creating a technically important but highly context-dependent opportunity for carbon restoration. This critical narrative review evaluates whether agronomic management can produce additional, measurable and sufficiently durable soil organic carbon (SOC) gains while maintaining agricultural production. Literature published from 1 January 1990 to 6 July 2026 was considered, with earlier or later-dated online records excluded from the evidentiary synthesis when outside this interval. The evidence indicates that SOC responses are governed principally by changes in plant-derived carbon inputs, microbial transformation, mineral association, aggregation, erosion and vertical redistribution rather than by any agronomic label alone. Cover crops, diversified rotations that increase biomass inputs, residue retention, perennial phases and agroforestry generally provide credible pathways for endogenous carbon accrual, although effect sizes vary with biomass production, soil mineralogy, climate, starting SOC and duration. Reduced and no-tillage frequently increase near-surface SOC but do not consistently increase whole-profile stocks when equivalent soil mass and deeper sampling are used, making tillage a particularly sensitive case for carbon accounting. Manure, compost and biochar can substantially increase measured soil carbon, but their climate value depends on carbon-source counterfactuals, processing emissions, displacement of organic resources and non-CO₂ greenhouse gases. Nutrient and water management can enhance SOC indirectly by increasing crop carbon inputs, yet gains must be evaluated against fertiliser-related nitrous oxide and energy emissions. Across practices, finite sink capacity, reversibility, spatial heterogeneity and measurement uncertainty constrain claims of permanent sequestration. The most defensible strategy is therefore not a universal practice hierarchy, but context-specific agronomic design that increases photosynthetic carbon inputs, protects soil from loss, verifies stock change across an appropriate soil mass and depth, and evaluates whole-system greenhouse-gas consequences. Future research should prioritise long-term, profile-scale, carbon-source-aware experiments and monitoring frameworks that connect total SOC change with particulate and mineral-associated fractions, crop performance, permanence and full greenhouse-gas accounting.

Climate-driven Harmful Algal Blooms and Marine Aquaculture: A Critical Appraisal of Early Warning, Fish Mortality, Exposure Mechanisms and Farm-level Adaptation

2026-09-26T13:17:24+00:00

Harmful algal blooms represent one of the few climate-sensitive hazards capable of destroying an entire marine farm's standing biomass within days, yet the scientific literature that underpins farm protection remains fragmented across oceanography, fish pathology, sensor engineering and resource economics. This review critically examines the evidence connecting climate variability and change to bloom hazard in aquaculture regions, the quantification of farmed fish mortality, the cellular and physiological mechanisms through which exposure becomes death, and the effectiveness of early warning systems and farm-level adaptation. Peer-reviewed literature was identified through structured searching of open scholarly databases and indexes, supplemented by backward and forward citation searching, and appraised for design adequacy, measurement validity, ecological realism and consistency with independent evidence. Four conclusions emerge with differing degrees of confidence. Attribution of increased bloom frequency to climate forcing remains contested at the global scale because observational effort has expanded alongside aquaculture itself, although regional attribution is considerably stronger where hydroclimatic anomalies have been reconstructed independently of bloom records. Mortality quantification rests largely on cell-abundance thresholds whose transferability between species, sites and years is weak, and which conflate very different killing mechanisms. Mechanistic work has converged on reactive oxygen species, lipophilic and polyketide toxins, and mechanical gill injury as complementary rather than competing pathways, but laboratory potency rankings predict field outcomes poorly because exposure dose, water-column structure and prior gill condition are rarely measured concurrently. Early warning systems have matured technologically while remaining substantially under-evaluated against operational decision criteria, and most farm-level mitigation measures are supported by mechanistic plausibility and small-scale trials rather than by controlled comparison at commercial scale. Priorities include standardised exposure reporting, prospective forecast verification against farm decisions, and evaluation of mitigation under realistic bloom conditions.

Managing Soil Acidity and Fe–Al Toxicity in Submerged Paddy Soils: Biogeochemical Processes, Environmental Implications and Integrated Amelioration Strategies

2026-09-28T10:40:39+00:00

Submergence transforms acidic rice soils into a dynamic biogeochemical environment in which redox potential, pH, iron and aluminium speciation, nutrient availability and microbial activity change throughout the cropping period. These transformations can partly alleviate aluminium toxicity through pH-mediated hydrolysis, while simultaneously increasing soluble Fe(II) through microbial reduction of Fe(III) minerals. Consequently, acid-affected submerged rice soils may experience a shifting combination of acidity, aluminium toxicity, iron toxicity and nutrient imbalance rather than a single, static constraint. This review synthesises the mechanisms governing these changes and evaluates the roles of liming materials, phosphogypsum, dolomite, magnesium sulphate, calcium silicate, organic amendments and biological approaches. Particular attention is given to the complementary functions of amendments: acidity neutralisation, calcium and magnesium supply, aluminium detoxification, silicon-mediated stress tolerance and modification of the rhizosphere environment. The review also considers water management and the environmental implications of amendment use, including nutrient imbalance, amendment quality, sulphur cycling and the need to avoid excessive inputs. Evidence indicates that no single amendment can reliably resolve all constraints in strongly acid, Fe-rich submerged soils. A site-specific strategy that integrates soil diagnosis, temporal monitoring, complementary amendment functions and appropriate water management is therefore more defensible than blanket application. Future research should combine time-resolved soil chemistry with plant responses, amendment interactions, environmental risk assessment and field-scale validation to develop resilient and resource-efficient management strategies for acid-affected rice ecosystems.

Benzophenone-3 in Aquatic Environments: Sources, Occurrence, Toxicity and the Prospects for Microalgae-based Bioremediation

2026-09-29T13:11:08+00:00

Benzophenone-3 (BP-3), also known as oxybenzone, is a widely used organic ultraviolet filter incorporated into personal care products, cosmetics, paints and sunscreens. Its photostability, lipophilicity and slow biodegradation promote environmental persistence and facilitate its entry into aquatic systems through recreational activities and wastewater treatment plant effluents. BP-3 has been detected in wastewater, surface water, seawater, sediments, soils and remote marine environments, with reported concentrations spanning ng L^-1 to mg L^-1. Both BP-3 and its transformation products are biologically active, and available evidence indicates endocrine-disrupting, genotoxic, behavioural, reproductive and photosynthetic effects across humans, fish, aquatic invertebrates, corals and microalgae. Conventional wastewater treatment shows variable removal, while advanced oxidation processes can achieve high degradation under controlled conditions but may be constrained by cost, incomplete mineralisation and transformation-product formation. Biological treatment is therefore of interest as a potentially lower-cost and environmentally sustainable option. Microalgae are particularly relevant because they can remove contaminants through bioadsorption, bio-uptake and biodegradation while simultaneously supporting nutrient removal, carbon dioxide fixation and biomass production. However, direct evidence for microalgae-mediated BP-3 removal remains limited. Further work should prioritise strain screening, environmentally realistic exposure conditions, real wastewater matrices, transformation-product characterisation, mixture effects and scale-up to clarify the practical feasibility of microalgae-based BP-3 bioremediation.

Biodiversity in the Republic of Guinea: Evidence, Threats, Conservation and Research Priorities — A Review and Bibliometric Map

2026-10-05T12:51:34+00:00

This evidence map characterises how biodiversity research concerning the Republic of Guinea is represented in a fixed OpenAlex record set and complements the literature map with an illustrative Global Biodiversity Information Facility (GBIF) occurrence-data sample. Ten English-language query families were run in OpenAlex on 22 July 2026, producing 852 unique records after identifier deduplication. Lexical and thematic screening yielded a fixed 120-record descriptive corpus. Because the source search was restricted to OpenAlex and the corpus may contain contextual regional records and different publication versions, it is treated as a bibliometric record set rather than an exhaustive systematic-review corpus; Guinea-specific narrative conclusions are restricted to studies with identifiable evidence from the country. Non-exclusive coding identified strong representation of forests and flora (89 records), conservation pressures, and primates and other mammals, with marked concentration in Forest Guinea, Mount Nimba and established primate-research sites. An illustrative subset of 2,996 georeferenced GBIF occurrences was drawn from 415,770 country-coded occurrences reported by the API at retrieval; this subset is used only to visualise data availability and not to estimate national richness or taxonomic composition. The mapped literature documents substantial biological value and recurring pressures associated with habitat conversion, infrastructure and mining, hunting, fire and wood extraction, and climate-related risks, while revealing uneven geographic and taxonomic coverage. Priority needs include harmonised national inventories, longitudinal observatories, research on neglected taxa, cumulative-impact assessment, protected-area evaluation, ecological connectivity, aquatic systems and community-centred monitoring. The analysis is therefore best interpreted as an exploratory map of a bounded indexed corpus that identifies research clusters and information gaps and provides a transparent foundation for a future multi-database systematic map and a national biodiversity data infrastructure.

Water Conservation and Irrigation Management in Natural Farming Systems: A Critical Review of Practices and Technologies

2026-10-07T09:28:53+00:00

Natural farming combines biological inputs, soil cover and crop diversification with reduced dependence on purchased agrochemicals, but its water-conservation claims require clearer separation of mechanisms, measurements and scales. This critical narrative review examines evidence on soil-water management, rainwater harvesting, irrigation scheduling and monitoring technologies, with particular attention to Indian natural farming and the transferability of wider agroecological research. Literature eligible through 30 July 2026 was selected through targeted searches of accessible scholarly records, institutional repositories and citation networks. Direct natural-farming experiments were distinguished from component studies, quantitative syntheses and mechanistic evidence. The strongest transferable support concerns management of soil cover, avoidance of unnecessary irrigation and context-specific scheduling. Evidence that complete natural-farming packages consistently reduce consumptive water use or groundwater depletion remains insufficient. Higher shallow soil moisture, infiltration, yield or irrigation water productivity cannot independently establish such reductions. Contrasting field results show that favourable performance in diversified farm trials should not be generalised to nutrient-demanding cereal systems, while omission experiments caution against attributing package effects to individual biological inputs. Living covers and trees can improve soil functioning yet compete for water; organic carbon accumulation does not guarantee a large increase in plant-available storage. Drip systems, alternate wetting and drying, simple soil-water indicators and remotely sensed evapotranspiration offer complementary opportunities, provided that calibration, maintenance, nutrient supply and water quality are addressed. A decision framework is developed around the limiting water process, an appropriate comparator, farmer capacity and the scale at which conservation is claimed. Immediate research priorities are replicated multi-season package-by-irrigation experiments, root-zone water balances, transparent nutrient accounting and evaluation of farm-to-catchment consequences. Natural farming is best treated as a context-dependent management system within which water conservation must be demonstrated, rather than as an intrinsically water-saving label.

Advances in Water Conservation and Irrigation Efficiency in Natural Farming: A Critical Review

2026-10-07T13:33:54+00:00

Natural farming brings renewed attention to biological soil management, local resource recycling and reduced dependence on purchased inputs, but its water-conservation claims require clearer hydrological interpretation. This critical narrative review examines evidence available through 27 June 2026, distinguishing evaluations of explicitly identified natural-farming systems from research on potentially transferable practices. Scholarly records, primary studies, evidence syntheses and authoritative irrigation guidance were assessed for treatment definition, comparator quality, measurement validity, temporal coverage and scale of inference. Recent Indian studies support the possibility of maintaining yields, improving selected soil properties and reducing production costs, although responses differ among crops and environments. These findings do not establish a general reduction in seasonal evapotranspiration or basin-scale water depletion. The strongest transferable evidence concerns surface residue management, context-sensitive irrigation scheduling and the integration of soil cover with controlled water delivery. Living cover can instead reduce water available to subsequent crops in dry environments, while increased soil carbon does not translate uniformly into large increases in plant-available storage. Microbial preparations have plausible biological functions, but their independent contribution to irrigation savings remains insufficiently resolved. Drip systems, buried pitchers, alternate wetting and drying in rice, and sensor-based scheduling offer distinct opportunities, subject to nutrient supply, salinity, maintenance and affordability constraints. Greater irrigation productivity may coexist with unchanged or increased total water consumption when farmers expand cropped area or intensify production. An integrated assessment therefore needs to separate soil condition, crop performance, farm withdrawals and catchment depletion rather than treating them as interchangeable benefits. Priority research should combine multi-season natural-farming comparisons, component experiments, measured water balances and implementation analysis. Natural farming is best understood as a context-dependent platform for improving water stewardship, not as an intrinsically water-saving label or a substitute for hydrological accounting.

Zeolites for Sustainable Agriculture: From Soil Amendment and Nutrient Retention to Environmental Remediation and Next-Generation Delivery Systems

2026-10-12T10:14:14+00:00

Agricultural intensification has increased pressure on soil, water and nutrient resources while accelerating nutrient losses, salinity, contaminant mobility and other environmental impacts. Zeolites—crystalline, hydrated aluminosilicates characterised by interconnected channels, cages, high cation-exchange capacity and reversible water sorption—offer a multifunctional mineral platform for addressing several of these challenges simultaneously. This review synthesises the supplied literature on natural and synthetic zeolites and reframes it around the central question of how zeolite structure and surface chemistry can be translated into measurable gains in agricultural resource-use efficiency and environmental protection. The evidence indicates that zeolites can modify soil physical properties, increase water retention, buffer soil acidity, retain ammonium and other cationic nutrients, reduce nutrient losses, and support slow-release fertiliser systems. Their adsorption and ion-exchange properties also underpin applications in heavy-metal immobilisation, pesticide removal, wastewater treatment and controlled delivery of agrochemicals. Natural clinoptilolite is particularly attractive because of its abundance, comparatively low cost and strong ion-exchange behaviour, whereas synthetic and modified zeolites provide opportunities for tailoring pore structure, surface charge and selectivity. However, responses are highly context dependent: soil texture, mineralogy, zeolite composition, particle size, application rate, pH, contaminant speciation and amendment combinations can alter outcomes. Recent research increasingly emphasises zeolite–biochar, zeolite–compost, organo-zeolite and nanozeolite systems, but field-scale validation, long-term environmental safety, economic assessment, standardised characterisation and life-cycle analysis remain insufficient.

Soil and Crop Management for Climate-Resilient Millet Production: Fertility, Water, Establishment and Cropping-System Strategies

2026-10-15T12:35:57+00:00

Millets are frequently described as climate-resilient cereals because several species maintain production under heat, intermittent drought and low-input conditions that constrain major cereals. That description is directionally correct but agronomically incomplete: resilience is strongly conditioned by soil fertility, rooting environment, rainfall timing, crop establishment, genotype, weed pressure and the way water and nutrients are co-managed. This critical narrative review evaluates soil and crop management strategies for sustaining and increasing millet production under changing climate conditions, with emphasis on pearl millet, finger millet and representative small millets in rainfed and semi-arid systems. Literature published from 2000 to 5 August 2026 was identified through AGRIS, PubMed, OpenAlex, OpenAIRE, DOAJ, Semantic Scholar and Google Scholar, supplemented by citation searching and authoritative institutional sources. Evidence was appraised for design quality, duration, environmental representativeness, resource-use measurements and transferability. Across the literature, the most defensible conclusion is that no single practice provides climate resilience across environments. Integrated nutrient management, site-specific fertiliser targeting, strategic microdosing, residue retention, moisture conservation, timely sowing, stress-adapted cultivars and diversified millet-legume systems can improve yield or resource-use efficiency, but benefits are highly contingent on soil constraints and rainfall pattern. Nutrient microdosing is effective in low-input Sahelian systems yet may create nutrient-balance risks when not paired with organic matter and wider nutrient replenishment. Sensor-guided or soil-test-based fertilisation is promising, although evidence remains geographically concentrated. Water management is most effective when aligned with reproductive-stage sensitivity and soil water storage rather than treated as an irrigation-only intervention. Intercropping can improve land productivity but does not uniformly buffer severe drought. Future progress requires multi-year, multi-location experiments that test management bundles, quantify yield stability and soil change, include economic and labour outcomes, and explicitly evaluate genotype-by-management-by-climate interactions. Climate-resilient millet production should therefore be framed as adaptive soil-crop system management rather than as an inherent crop property.

Application of the SCS–CN Method Integrated with GIS and Remote Sensing for Watershed Runoff Estimation: A Review

2026-10-16T08:10:49+00:00

Accurate estimation of runoff is crucial for watershed planning, soil and water conservation, flood mitigation, and the management of ungauged watersheds. The Soil Conservation Service Curve Number (SCS-CN) method has been extensively used because of its minimal input requirements and its ability to model the spatial influence of land use, soil properties, and hydrologic soil groups. This review compiles applications of the GIS-based SCS-CN method reported for watersheds in semi-arid and monsoon-affected countries such as India, Saudi Arabia, Afghanistan, China, Iraq, and Ethiopia. The reviewed literature employed rainfall data, land-use/land-cover data, soil maps, hydrologic soil groups, digital elevation models, and watershed morphometry to calculate curve numbers and direct runoff. The reported CN values varied substantially, from about 40 under dry conditions to more than 90 under urban, rocky, agricultural, or poorly infiltrating conditions. Runoff estimates ranged from relatively low values in arid catchments to more than 1,300 mm per year in high-rainfall watersheds. Several studies reported high R² correlations between observed and estimated runoff, typically ranging from 0.73 to 0.98. Important limitations identified in the review include the sensitivity of results to the choice of curve number, antecedent moisture condition, initial abstraction assumption, land-use classification, soil-group assignment, rainfall representation, and the lack of observed discharge data. The overall design of the SCS-CN method and its integration with RS and GIS offer a practical approach to assessing spatial runoff and prioritising watersheds, but the method requires local calibration, uncertainty analysis, and validation against observed rainfall–runoff data.

Microbial Consortia and Nano-fertilizers for Sustainable Nutrient Management in Wheat: A Review

2026-10-16T12:58:33+00:00

Wheat (Triticum aestivum L.) production requires nutrient-management strategies that sustain productivity and grain quality while addressing declining soil fertility and variable environmental conditions. This narrative review examines the individual and potential integrated roles of microbial consortia and nano-fertilisers in sustainable wheat cultivation. The reviewed literature indicates that functionally complementary microorganisms can support biological nitrogen fixation, phosphorus solubilisation, potassium and micronutrient mobilisation, root development and rhizosphere activity. Nano-fertilisers, including nano-urea, nano-DAP and micronutrient formulations, may improve nutrient delivery, regulate nutrient release and contribute to nutrient-use efficiency when used appropriately. The combination of biological nutrient mobilisation and nano-enabled nutrient supply offers a conceptual basis for more coordinated nutrient management. However, responses depend on microbial compatibility, formulation properties, application rates, soil conditions, crop genotype and environmental variability. Evidence for consistent benefits from directly integrated microbial–nano treatments in wheat remains limited, and favourable results from either technology alone cannot establish synergistic effects. Nano-fertilisers should therefore be evaluated as potential supplements to balanced basal fertilisation rather than universal substitutes. Further research requires comparative, multi-location field studies and long-term assessment of soil biological activity, nutrient losses, grain nutritional quality, environmental safety and economic feasibility. Standardised approaches to consortium selection, formulation assessment and agronomic evaluation could help clarify the suitability of integrated systems for sustainable wheat nutrient management.

Wild Silks in a Changing World: Biodiversity, Climate Resilience and Sustainable Futures for Tasar, Eri and Muga Sericulture

2026-10-22T13:32:31+00:00

Tasar, eri and muga silks occupy distinctive ecological and cultural positions within Asian sericulture, yet they are frequently grouped under an undifferentiated label of “wild” or “sustainable” silk. Such terminology obscures differences in domestication, host-plant dependency, exposure to climatic extremes, landscape governance, cocoon processing and livelihood organisation. This critical narrative review examines evidence concerning the tropical tasar moth Antheraea mylitta, eri moth Samia ricini and muga moth Antheraea assamensis, with particular attention to India and relevant comparative evidence. Scholarly literature, verified primary research, methodological reviews and institutional records available through 10 August 2026 were considered, using a thematic appraisal of study design, ecological scale, causal inference and transferability. Evidence indicates that host-plant quality, rearing season and local insect–environment interactions materially influence production, whereas genetic studies caution against equating named tasar ecoraces with discrete, independently adapted evolutionary lineages. Heat-stress experiments establish physiological responses in particular tissues or larval stages but cannot by themselves predict farm-level survival under combined heat, rainfall and disease exposure. Climatic distribution models identify plausible areas of changing environmental suitability for muga and its hosts, although projected suitability is not an observed productivity trend. Livelihood surveys show locally significant economic opportunities, especially in eri-based systems, but their findings depend on labour valuation, sampling and market access. Likewise, life-cycle evidence from domesticated silk cannot establish the environmental superiority of non-mulberry silks. An integrated resilience framework is advanced in which genetic resources, host landscapes, seed and rearing quality, disease surveillance, equitable institutions and verified environmental performance are jointly assessed. Priority research requires linked multi-location field experiments, genetic and phenological monitoring, comparable farm accounts, and transparent life-cycle studies. The evidence supports context-specific diversification and stewardship, not unconditional claims that wild silk is climate-proof, biodiversity-positive or intrinsically sustainable.

Quantifying the Urban–forest Trade-off in a Rwandan Secondary City: A 35-Year Multi-temporal Remote Sensing Assessment of Huye District (1990–2025)

2026-09-21T09:30:05+00:00

Rapid urban expansion is transforming land-cover patterns in Rwanda’s secondary cities, with potential consequences for forest resources and sustainable land-use planning. This study assessed long-term changes in built-up and forest cover associated with urban expansion in Huye District, Rwanda, from 1990 to 2025, and examined the spatial relationship between built-up expansion and forest-cover decline. A multi-temporal remote sensing approach was applied using Landsat imagery for four reference years (1990, 1999, 2018, and 2025). The imagery was pre-processed and classified using supervised maximum-likelihood classification into five land-cover classes, with classification accuracy assessed using error-matrix analysis and ground-reference data, achieving overall accuracies exceeding 85% for all years. Post-classification change detection quantified land-cover transitions and changes in built-up and forest areas, while Pearson correlation analysis assessed the association between built-up and forest areas, and a 5-km proximity buffer was used to examine the spatial concentration of forest-cover loss around expanding built-up areas. Built-up land increased from 2.80 km² (0.52% of the district) in 1990 to 49.30 km² (8.94%) in 2025, representing a 1,660.71% increase, while forest cover declined from 74.50 km² (13.79%) to 35.20 km² (6.51%), corresponding to a 52.75% reduction. Consequently, the built-up-to-forest area ratio shifted from approximately 1:26.6 in 1990 to 1.40:1 in 2025, indicating a substantial reversal in the relative extent of these land-cover types. Built-up and forest areas exhibited a strong inverse association across the four observation years (Pearson r = −0.92), although the relationship was not statistically significant at the 5% level (p = 0.078; n = 4). Spatial analysis further indicated that forest-cover loss was disproportionately concentrated within the 5-km zone surrounding expanding built-up areas. Overall, Huye District experienced substantial built-up expansion accompanied by pronounced forest-cover decline over the 35-year period. The strong inverse temporal association and concentration of forest loss near expanding built-up areas suggest that urban growth is an important spatial correlate of forest-cover change, although the limited number of temporal observations constrains statistical inference. The findings highlight the need to integrate forest conservation into secondary-city expansion planning through enforceable urban growth boundaries, protection of forested buffer zones, and targeted reforestation and restoration measures.

Agronomic Evaluation of Suitable Cropping Systems for Bidi Tobacco under Rainfed Conditions in Andhra Pradesh

2026-09-21T09:36:50+00:00

A field experiment was conducted for Agronomic evaluation of suitable cropping systems for bidi tobacco under rainfed conditions at Regional Agricultural Research Station, Nandyal, ANGRAU under AINP on Tobacco for three years during rabi seasons from 2020-21 to 2022-23 with the objective to evaluate different bidi tobacco based cropping systems for higher productivity, monetary returns and quality of bidi tobacco. The experiment laid out in randomized block design with 3 replications. Treatments comprised of 9 cropping systems viz., Foxtailmillet – Bidi tobacco, Greengram – Bidi tobacco, Blackgram – Bidi tobacco, Sweet corn – Bidi tobacco, Cluster bean – Bidi tobacco, Cowpea – Bidi tobacco, Bajra – Bidi tobacco, Onion – Bidi tobacco and Fallow- bidi tobacco. The pooled results revealed that significantly higher leaf length and width, bidi tobacco equivalent yield (3119 kg/ha) were recorded with Onion followed by bidi tobacco cropping system which is on par with sweetcorn followed by bidi tobacco cropping system. Whereas higher net returns (Rs. 202815/ha) and benefit cost ratio (3.5) was observed in sweet corn followed by bidi tobacco cropping system. Land-use efficiency (LUE) was the highest in onion-bidi tobacco cropping system (90.4 %) and the lowest in Fallow-bidi tobacco cropping system (49.3%). Significantly higher system productivity (9.9 kg/ha) and system profitability (676 Rs./ha) were registered with Sweet corn – Bidi tobacco cropping system. Leaf chemical parameters viz., higher nicotine (6.67 %), reducing sugars (3.90 %) and chlorides (1.21 %) were recorded in onion-bidi tobacco cropping system. Thus, Onion-bidi tobacco and Sweetcorn- bidi tobacco cropping system were more productive and remunerative than the other cropping systems in bidi tobacco growing areas of Kurnool district of Andhra Pradesh.

Agronomic Performance and Soil Chemical Responses of Kharif Rice to Balanced and Reduced P and K Supply in the Red and Lateritic Soils of Paschim Medinipur, West Bengal, India

2026-09-21T11:36:02+00:00

Balanced fertilisation is essential for sustaining rice productivity and maintaining soil fertility, particularly in acidic red and lateritic soils where nutrient availability and retention can be limiting. Although nitrogen is commonly applied to enhance rice growth, its effectiveness depends on an adequate supply of phosphorus and potassium. However, the short-term agronomic, soil-fertility and economic consequences of reducing or omitting phosphorus and potassium under a fixed nitrogen supply remain insufficiently characterised for Kharif rice in Paschim Medinipur, West Bengal. A field experiment was conducted during the Kharif season of 2025 at the Agricultural Experimental Field of Midnapore City College, Paschim Medinipur, West Bengal, India, to evaluate the effects of different NPK combinations on rice (Oryza sativa L.) growth, yield, post-harvest soil chemical properties and economic performance under red and lateritic soil conditions. The experiment was laid out in a Randomised Block Design with seven treatments and three replications. Nitrogen was maintained at 80 kg ha⁻¹ in all fertilised treatments, while P₂O₅ and K₂O were supplied at recommended, reduced or omitted levels. Treatments were T1 (80:40:40), T2 (80:40:20), T3 (80:40:0), T4 (80:20:40), T5 (80:0:40), T6 (80:20:20) and T7 (0:0:0 kg N:P₂O₅:K₂O ha⁻¹). Growth, yield attributes, yield, post-harvest soil pH, EC, organic carbon and available N, P and K, along with economic returns, were assessed. T1 recorded the highest values for most growth and yield attributes. Grain yield was highest under T1 (5.06 t ha⁻¹), followed by T2 (4.84 t ha⁻¹) and T4 (4.73 t ha⁻¹), while T7 recorded the lowest yield (2.19 t ha⁻¹). T1 increased grain yield by 131.1% over the control; however, its yield was statistically comparable with T2 and T4. Treatments involving P or K omission generally reduced growth and yield. Post-harvest soil analysis showed comparatively higher available N, P and K and organic carbon under nutrient-supplied treatments. T1 also recorded the highest gross return (₹139,363 ha⁻¹), net return (₹86,279 ha⁻¹) and B:C ratio (1.63). The study indicates that balanced NPK supply improved rice productivity, post-harvest soil chemical status and economic returns under the experimental conditions, although multi-season and multi-location evaluation is required for wider recommendation.

Seasonal Incidence of Pod Borer Complex of Pigeonpea in Relation to Weather Parameters at Sehore, Madhya Pradesh, India

2026-09-22T09:44:23+00:00

The present field investigation was conducted to study the seasonal incidence of pod borer complex of Pigeonpea during Kharif 2025 at the Research Farm of Entomology Department, Rafi Ahmed Kidwai College of Agriculture, Sehore (Madhya Pradesh). Pigeonpea, Cajanus cajan (L.), is the second most important pulse crop after chickpea. India is the world's largest producer of Pigeonpea. The study revealed that pigeonpea was infested by four major pod borers, i.e. gram pod borer, Helicoverpa armigera; leaf webber, Grapholita critica; plume moth, Exelastis atomosa and spotted pod borer, Maruca vitrata. The pests first appeared between the 36th and 41st standard meteorological week and persisted up to the 2nd and 3rd standard meteorological week of the following year attaining peak populations during the 45th - 47th standard meteorological week during the crop period. Correlation studies showed that maximum temperature had non-significant negative correlations (r= -0.328, and -0.030, respectively). Correlation studies revealed that minimum temperature, relative humidity and rainfall had negative and non-significant correlations (r= -0.436, -0.422, -0.413; -0.059, -0.031, -0.263 and -0.192, -0.172, -0.341, respectively) with Gram pod borer, plume moth and spotted pod borer, while maximum temperature showed positive, non-significant associations with leaf webber and plume moth (r= 0.394 and 0.131, respectively). The weak and statistically non-significant correlations with temperature, relative humidity and rainfall indicate that these weather parameters alone did not have a significant influence on pest larval population dynamics during the study period.

Assessing Division-level Variability in Soil Nutrient Retention in a Tropical Forest Reserve: Evidence from the Amrabad Tiger Reserve, India

2026-09-22T12:30:03+00:00

Aim: The present study aimed to evaluate division-wise variability and interrelationships of key soil physico-chemical properties governing nutrient retention in the Amrabad Tiger Reserve (ATR), a tropical dry deciduous forest ecosystem of the Eastern Ghats, India.

Study Design: A field-based observational study was conducted, and the data were statistically analysed using one-way analysis of variance (ANOVA) followed by Tukey’s HSD test, along with Pearson’s correlation analysis to examine relationships among variables.

Place and Duration of the Study: Soil sampling was carried out across three administrative divisions—Achampet, Amrabad, and Nagarjuna Sagar—within the Amrabad Tiger Reserve, Telangana, India, from 2023 to 2025.

Methodology: A total of 100 composite soil samples were collected from ten forest ranges at a depth of 0–15 cm. Samples were analysed for soil reaction (pH), electrical conductivity (EC), organic carbon (OC), and available nitrogen (N), phosphorus (P), and potassium (K) using standard and widely accepted laboratory procedures. Statistical analyses were employed to assess spatial variability and interrelationships among soil properties.

Results: Significant division-wise variation was observed for soil pH, EC, and available N, P, and K (p < 0.01), whereas organic carbon did not differ significantly among divisions. Nagarjuna Sagar soils exhibited higher pH but comparatively lower nitrogen availability, while Amrabad showed superior nutrient status, particularly for nitrogen, phosphorus, and potassium. Pearson’s correlation analysis identified organic carbon as a key regulator of nutrient availability, showing strong positive associations with available nitrogen (r = 0.355) and potassium (r = 0.381).

Conclusion: The study reveals pronounced spatial heterogeneity in soil nutrient retention within ATR, driven by fine-scale variations in geomorphology, vegetation, and organic matter dynamics. Organic carbon emerged as the central factor controlling nutrient availability, underscoring the need for site-specific soil management and conservation strategies to sustain productivity and ecosystem resilience in tropical dry forest reserves.

Climate Change, Length of Extreme Heat Waves in Tahoua (Niger) during the Year 2024

2026-09-22T13:33:14+00:00

Extreme heat during the March-April-May hot season is an important climatic concern in Tahoua, Niger. This study assessed the duration of heatwaves in Tahoua city during 2024 using daily maximum temperature observations from the Tahoua station. Two identification approaches were compared: the absolute 40°C threshold used by ACMAD, under which a heatwave occurs when the maximum temperature exceeds 40°C for at least three consecutive days, and percentile-based thresholds at the 85th, 90th, and 95th percentiles. The threshold approach identified eight periods of sustained high temperature during March-April-May, including several episodes lasting at least three consecutive days. The percentile analysis showed that estimated heatwave duration depended strongly on the selected percentile. At the 95th percentile (43.7°C), one heatwave episode lasting 5 days was identified. At the 90th percentile (42.8°C), four heatwave episodes lasting 4–9 days were recorded. At the 85th percentile (41.6°C), six episodes lasting 3–19 days were identified, including longer events from late March to early April and from late April to early May. These results demonstrate that the estimated number and duration of heatwave episodes in Tahoua during 2024 varied with the operational threshold used. The findings provide a station-level description of extreme-heat duration during the 2024 hot season and support careful selection of percentile or absolute thresholds when characterising heatwave conditions in Tahoua.

Impact of Abiotic Factors on Arthropod Communities and Natural Enemies in Paddy (Oryza sativa L.) - Based Agro and Agroforest Ecosystems

2026-09-26T13:30:27+00:00

Weather variables can influence the abundance and distribution of arthropods in rice ecosystems, including both pest taxa and their natural enemies. This study evaluated arthropod abundance and its association with selected abiotic factors in a paddy agroecosystem and paddy agroforest ecosystem at Kanchanpally village, Kowdipally Mandal, central Telangana, during the 2024 Kharif season (July–November). One-acre plots representing the two ecosystem types were sampled using pitfall, sticky and pheromone traps, visual counts and sweep netting. Maximum and minimum temperature, maximum and minimum relative humidity, and rainfall were related to arthropod populations by correlation analysis. A total of 3,618 arthropod individuals were recorded, comprising 1,712 individuals in the agroecosystem and 1,906 in the agroforest ecosystem. Weather relationships varied among arthropod orders and between ecosystems. For Lepidoptera, rainfall was significantly negatively correlated with abundance in the agroecosystem (r = −0.539) but significantly positively correlated in the agroforest ecosystem (r = 0.581). Natural enemies were more numerous in the agroforest ecosystem (765 individuals) than in the agroecosystem (623 individuals). Rice yield was 6,918.8 kg ha⁻¹ in the agroforest ecosystem and 6,424.6 kg ha⁻¹ in the agroecosystem, corresponding to a 7.69% increase. The findings indicate ecosystem-specific relationships between weather variables, arthropod communities and natural-enemy abundance, while supporting further investigation of agroforest-based paddy systems.

Evaluation of an Experimental Climate Information of Health Product for Vector-borne Diseases: An Initiative towards Climate Services for the Health Sector in India

2026-09-28T10:21:34+00:00

Aims: To evaluate the usefulness of the experimental Climate Information for Health (CIH) product issued by the India Meteorological Department (IMD) for malaria and dengue against observed disease-occurrence data for 2017.

Study Design: A retrospective, observational verification study using categorical (contingency-table) analysis of forecast climatic suitability against reported vector-borne disease (VBD) occurrence.

Place and Duration of Study: Office of Climate Research and Services, India Meteorological Department, Pune, India, covering all Indian states/meteorological subdivisions from May to December 2017.

Methodology: As a requirement of the WMO Global Framework for Climate Services (GFCS), IMD initiated weekly Climate Information for Health (CIH) bulletins for malaria and dengue on an experimental basis. The bulletins used two-week-ahead maximum/minimum temperature forecasts from its Extended Range Prediction System (ERPS) and were issued every Friday from the second week of May 2017. States were classified into four categories according to whether climatic suitability for VBD occurrence was anticipated and whether the disease was subsequently reported, using monthly, state-wise disease data from the National Vector Borne Disease Control Programme, FluTrackers, state health departments and municipal corporations. Skill scores (probability of detection, false alarm ratio, miss rate, bias, critical success index and Heidke skill score) were computed from the resulting contingency tables.

Results: CIH was found to be useful for malaria in most states and months from June to October 2017 (probability of detection [POD] ≈ 0.97; false alarm ratio [FAR] ≈ 0.03). For dengue, its usefulness was limited to the winter months of November and December (POD ≈ 0.38; FAR ≈ 0.11 for the full study period). This was attributable mainly to the absence of a validated maximum-temperature threshold for dengue transmission in the Indian context.

Conclusion: The experimental CIH product provides a useful, low-cost early signal for malaria risk in India and a starting point for dengue, but region-specific temperature (and possibly humidity and rainfall) thresholds for dengue transmission need to be developed in collaboration with the health sector to improve its reliability outside the winter season.

Stakeholders' Strategies and Channels of Climate Communication in the Bamenda Highlands, Cameroon

2026-09-30T12:46:59+00:00

This paper assesses the current communication strategies and channels used by different stakeholders in disseminating climate information in the Bamenda Highlands of Cameroon. The assessment goes beyond cataloguing what exists to examine whether the identified strategies and channels are capable of communicating climate variability and change information effectively. Climate variability and change information is understood here as scientifically grounded content on shifting rainfall patterns, temperature trends, increasing frequency of extreme weather events, and the consequences of these shifts for agricultural systems and community livelihoods. Drawing on a mixed-methods design that combined a stratified survey of 408 respondents, 30 key-informant interviews, eight focus-group discussions and 45 structured field observations across eight Sub-Divisions (Bamenda I–III, Kumbo Central, Nkambe Central, Santa, Oku and Fundong), the study maps participatory methods, media channels, institutional actors and communication frequency. Focus-group discussions dominate participatory approaches, yet function mainly as general environmental sensitisation rather than structured climate-science communication. Heat maps, a correlation matrix, labelled scatter plots and radar profiles of the eight Sub-Divisions show that regular programming co-varies with private weather services and independent media, that reactive communication is the statistical inverse of that cluster, and that mobile applications substitute for radio–television combinations in the most infrastructure-poor settings. Citizen-science initiatives remain under-utilised despite their direct relevance to local observation and monitoring. Radio, often combined with television or mobile applications, is the principal channel; dedicated climate-variability content is limited even in the best-performing programmes. Local NGOs are the most visible stakeholders but operate largely in isolation from government meteorological services, private weather companies and academic institutions, and three Sub-Divisions have no independent media outlet at all. Communication is predominantly reactive (when the need arises), with regular monthly and daily programming remaining marginal even in the best-resourced administrative centres. The findings reveal systemic fragmentation and call for a Regional Climate Communication Coordination Platform under the Ministry of Environment, Protection of Nature and Sustainable Development to serve as a network administrative organisation capable of aligning strategies, channels, and content standards.

Adaptive Capacity of Resettled Flood-prone Communities to Recurring Floods in Tana River County, Kenya

2026-09-28T12:58:18+00:00

This study evaluated whether resettlement had strengthened the capacity of flood-prone communities in Tana River County, Kenya, to anticipate, withstand, respond to and recover from recurring flood events. A household-based approach was used to assess socioeconomic characteristics, adaptation strategies, perceived effectiveness, institutional support and factors influencing adaptive capacity among 185 valid respondents. Descriptive statistics, Pearson’s chi-square tests and binary logistic regression were used to analyse the data. Early evacuation was the most widely adopted adaptation strategy (85.4%), followed by relocation to safer ground (78.4%) and livestock relocation (74.1%), while construction of barriers was least common (37.3%). Early warning was perceived as the most effective adaptation measure (M = 4.32, SD = 0.71), followed by evacuation (M = 4.18, SD = 0.76), whereas institutional support received the lowest effectiveness rating (M = 3.41, SD = 1.08). Socioeconomic factors, including education, income and livelihood diversification, were significantly associated with adaptive capacity (p < 0.05). Logistic regression showed that early-warning access had the strongest influence on adaptive capacity (AOR = 2.58, 95% CI: 1.39–4.79, p = 0.003), followed by livelihood diversification, education, community participation, income, institutional support and previous flood experience. The study concludes that resettlement alone was insufficient to ensure high adaptive capacity and that resilience depended on complementary socioeconomic, institutional and community-level support. The study recommends strengthening early-warning systems, livelihood diversification, disaster-preparedness training, institutional coordination, community participation and post-resettlement infrastructure and social services to enhance long-term resilience to recurring floods.

Flood Inundation Assessment in the 9th District of N'Djamena, Chad, Using an Integrated HEC-HMS-HEC-RAS Framework

2026-09-29T13:06:29+00:00

Flooding is a major natural hazard in rapidly growing African cities, where hydrological variability, urban expansion, and limited drainage capacity can increase exposure. N'Djamena, the capital of Chad, is recurrently affected by flooding associated with the Chari-Logone River system. The Chari-Logone watershed forms the principal active drainage area of the Lake Chad Basin and covers approximately 613,000 km². This study evaluates an integrated HEC-HMS, HEC-RAS, and Geographic Information System workflow for reconstructing historical flood conditions in neighbourhoods of the 9th District of N'Djamena. Hydro-climatic conditions for 2021-2023 were analysed, and the 2023 monthly discharge series at the N'Djamena station was used for HEC-HMS calibration. The calibration produced a Nash-Sutcliffe efficiency (NSE) of 0.50, a root mean square error (RMSE) of 562.93 m³/s, and a Pearson correlation coefficient (r) of 0.86. These statistics indicate moderate calibration performance, with a substantial overestimation of the principal discharge peak. HEC-HMS outputs were subsequently used in HEC-RAS to generate flood-inundation maps for 2021, 2022, and 2023. The mapped patterns were qualitatively consistent with historically affected areas, although no independent spatial accuracy metric was available for flood extent or depth. The modelling framework therefore provides a useful basis for historical inundation assessment and planning support, while its predictive application requires independent hydrological and spatial validation.

Climate-Smart Agriculture (CSA): An Alternative to Relief for Producers in Southeastern Benin

2026-10-01T14:27:52+00:00

Climate variability represents a major challenge for rain-fed agricultural production systems in southeastern Benin. This study analyses the relationships between climate variability, agro-climatic constraints, and crop production and examines potential adaptation and environmental sustainability options within the framework of Climate-Smart Agriculture (CSA).

The methodological approach combines long-term rainfall data from Météo-Bénin, agricultural statistics from the Ministry of Agriculture, Livestock and Fisheries (MAEP) for the period 1995–2018, demographic and socio-economic data from the 2013 Population and Housing Census, and field surveys conducted among 205 farming households.

The results show marked interannual rainfall variability, with 50% of the years analysed classified as dry, 38.16% as wet, and 11.84% as normal. However, no consistent relationship was found between annual rainfall totals and interannual variations in maize, cassava, cowpea, and groundnut yields. Crop performance appears to be more closely associated with rainfall distribution during the growing season and with the occurrence of critical events such as dry spells, delayed onset and early cessation of the rainy season, floods, and high-temperature events at sensitive stages of crop development. Farmers’ perceptions support this interpretation: delayed onset of the rainy season was the most frequently reported climatic constraint (25%), followed by early cessation of rainfall (20%). These disturbances can induce water stress and disrupt cropping calendars and crop development, thereby contributing to production losses and reduced farm income, with potential consequences for household food security. Adaptation options include the use of improved varieties (short-cycle and/or drought- and disease-resistant varieties), soil mulching (using crop residues or polyethylene film), and the Improved Production System (IPS)—involving crop sequencing and rotation—as well as sowing management (re-sowing, overseeding, stale seedbed techniques, dry sowing, and adjusting sowing dates). Agroforestry, capacity building for family farmers, and climate micro-insurance and safety nets for Climate-Smart Agriculture constitute the main mitigation measures in southern Benin. Overall, the results highlight the importance of combining climatic observations with farmers’ local knowledge to identify critical agro-climatic events better and support locally appropriate Climate-Smart Agriculture strategies.

Assessment of Grain Micronutrient Concentrations in Bread Wheat Generations under Early Heat Stress and Timely Sown Conditions

2026-10-03T13:34:30+00:00

Background: Wheat grain micronutrient deficiencies, particularly of iron and zinc, remain an important nutritional concern, highlighting the need for biofortification of widely consumed staple crops. Grain micronutrient accumulation is influenced by both genetic and environmental factors, including heat stress, making the identification of mineral-dense and heat-tolerant wheat genotypes important for breeding programmes.

Aim: This study assessed grain iron (Fe), zinc (Zn), copper (Cu) and manganese (Mn) concentrations across six bread wheat crosses and their P₁, P₂, F₁, F₂, BC₁ and BC₂ generations under early heat stress and timely sown conditions, and identified entries with potential for mineral biofortification breeding.

Study Design: Six wheat crosses, each represented by six generations (P₁, P₂, F₁, F₂, BC₁ and BC₂), were evaluated in a randomised block design with three replications.

Place and Duration of Study: Research Farm, Wheat and Barley Section, Department of Genetics and Plant Breeding, CCS Haryana Agricultural University, Hisar, India; Rabi 2024-25.

Methodology: Grain Fe, Zn, Cu and Mn were estimated by microwave-assisted acid digestion and atomic absorption spectrophotometry under early heat stress (E₁, sown 25 October 2024) and timely sown (E₂, sown 22 November 2024) environments. A standardised multi-mineral index (MMI) was computed from mineral z-scores, and its association with yield and heat-response indices was examined.

Results: All four minerals showed exploitable variation across generations and environments, with concentrations consistently higher under early heat stress. The F₁ generation recorded the highest mean concentration for all four minerals and the highest MMI. Fe, Zn and Mn were positively interrelated, while Cu showed the strongest association with heat resistance and yield-related traits.

Conclusion: PBW 872 × DBW 327 was the most promising cross for broad-spectrum mineral enrichment, while DBW 187 × DBW 327 combined elevated Cu with superior heat tolerance. Selected hybrid and backcross entries from these crosses are recommended for further selection and validation in wheat biofortification breeding programmes.

Seasonal Dynamics of Major Insect Pests of Cocoa (Theobroma cacao L.): A Field Survey in Andhra Pradesh, India

2026-10-03T13:41:40+00:00

Background: Cocoa cultivation in Andhra Pradesh has expanded rapidly, and insect pests are now a leading biotic constraint on tree vigour and pod yield, with their occurrence fluctuating by season and prevailing weather.

Aims: To quantify seasonal incidence of major cocoa insect pests, test the consistency of seasonal patterns across years, and relate incidence to weather parameters.

Study Design: Three-year longitudinal roving survey from February 2023 to January 2026. Place and Duration of Study: Twelve farmer-managed cocoa farms, Eluru district, Andhra Pradesh, India (16°42′N, 81°06′E); 2023 to 2025.

Methodology: Monthly pest incidence was recorded from 100 unsprayed trees per farm. Seasons were defined as summer (February–May), monsoon (June–September) and post-monsoon (October–January). The seasonal and annual incidence of major pests in the cocoa agroecosystem was assessed. The consistency of seasonal incidence across years, the influence of the year × season interaction, and the influence of weather parameters on seasonal incidence were also statistically analysed.

Results: Conogethes punctiferalis (husk borer), Indarbela sp. (bark-eating caterpillar), Planococcus citri (citrus mealybug) and Pseudococcus longispinus (long-tailed mealybugs) were dominant in all years. Peak incidence of lepidopteran pests declined progressively, with husk borer infestation decreasing from 68.38 ± 5.55% (2023-24) to 23.02 ± 3.18% (2025-26), and bark-eating caterpillar incidence from 51.81% to 8.38%. Mealybug incidence peaked post-monsoon during the first two survey years (citrus mealybug 34.79% and 32.73%) but shifted to summer in 2025-26 (35.79%). Year × season interactions were highly significant (p < 0.01) for all four pests. Lepidopteran pests were more strongly associated with relative humidity (r = −0.46 to −0.64) than with temperature (r = 0.41–0.42). Citrus mealybug correlated negatively with rainfall (r = −0.43, p = 0.01), while long-tailed mealybug showed no significant weather association.

Conclusion: The seasonality of lepidopteran pests was directionally stable, consistently peaking in summer with declining amplitude across years, whereas both mealybug species shifted their peak incidence from post-monsoon to summer in 2025-26, a directional change not fully explained by the weather associations tested here. Seasonal structuring can therefore vary in both amplitude and direction, limiting calendar-fixed control. Monitoring should focus on the summer months for husk borers and bark-eating caterpillars, and the post-monsoon period for mealybugs. Allowance should be made for seasonal shifts in years when the weather is inconsistent.

Changing Urban Forest Cover and Climate Variability in Bamenda, Cameroon: A Spatio-temporal Assessment

2026-10-06T09:50:14+00:00

This paper examines how urban forest change and climate variability jointly shape hazard exposure in Bamenda. Using a mixed-methods design, it combines Landsat classification (1984, 2004, 2025), a 75-year rainfall series (1951-2025), a temperature window (1984-2023), a 400-household survey, key-informant interviews and field observation, organised within an analytical framework where regional climate provides the trigger, urban forest and built form modify exposure, and household capacity conditions sensitivity. City-wide forest fell from 11,170.8 ha in 1984 to 10,856.3 ha in 2025 (-2.8%), but municipal trajectories diverged: Bamenda I lost 38.8%, and Bamenda III lost 22.3%, while Bamenda II gained 51.6%. Mean monthly rainfall intensity declined from 213.4 mm (1951-1970) to 139.4 mm (2011-2025), with a highly significant trend of -1.17 mm yr⁻¹ (R²=0.581; p=2.04×10⁻¹⁵). Mean temperature rose from 18.56°C (1984-1990) to 22.97°C (2013-2023). Standardized Precipitation Index (SPI) shifted from wet extremes in the 1950s-1960s to severe-to-extreme drought after 2007, including 2016 (SPI=-2.49) and a six-year severe-drought run from 2020 to 2025. Visual analytics, including graphs, heat maps, box plots, scatter plots, correlation matrices and spider charts, make co-movements visible. Flooding in Mulang, Ndamukong, Ngomgham and Ntarinkon and slope instability in Abangoh, Sisia and Mbatu are interpreted as joint outcomes of a drier, more variable climate and fragmented forest. Forest loss is thus not mere vegetation loss but a component of the climate-hazard-vulnerability nexus, amplifying flood, erosion, landslide and heat risks when combined with impervious-surface growth and settlement on floodplains and steep slopes. The following recommendations are drawn: reconstructing a quality-controlled monthly archive for Walsh-Lawler SI, SPI-3/6 and onset; adopting 2008, 2014, 2016 as design drought years while retaining flood/slope preparedness for wet extremes like 2013; sizing storage for multi-year drought; governing forest as hazard infrastructure, enforcing floodplain/slope regulation with a unified risk map and embedding annual SPI heat-maps and forest-stock visuals in climate communication.

When Extreme Heat Becomes the Norm in Ouagadougou, Burkina Faso

2026-10-06T10:21:09+00:00

Aims: To analyse the evolution of maximum temperatures and characterise thermal extremes in Ouagadougou between 1973 and 2025.

Study Design: Retrospective observational time-series study based on daily meteorological observations and extreme value analysis.

Place and Duration of Study: Ouagadougou, Burkina Faso, using observations covering the 1973-2025 period.

Methodology: Daily data from the Global Historical Climatology Network-Daily (GHCN-D) were analysed. The annual 90th percentile of TMAX (q90_TMAX) was assessed using the Mann-Kendall trend test and Sen's slope. Annual maxima were modelled with the generalised extreme value (GEV) distribution, while a generalised Pareto distribution (GPD) was fitted to exceedances above q90_TMAX. Model adequacy was assessed using graphical diagnostics and the Anderson-Darling test.

Results: The mean daily maximum temperature was 35.46 °C and the observed maximum reached 49.6 °C. q90_TMAX showed a highly significant increasing trend (τ = 0.437; P < .001), with Sen's slope estimated at 0.38 °C per decade (95% CI: 0.25-0.50). The GEV fit to annual maxima was not rejected at the 5% level (Anderson-Darling = 2.3496; P = .060), whereas the GPD fit was rejected (P < .001). GEV return levels were 42.90 °C at 2 years, 44.42 °C at 5 years, 45.33 °C at 10 years, and 47.10 °C at 50 years.

Conclusion: Extreme heat has become a recurrent hazard in Ouagadougou, highlighting the need to strengthen early warning, urban planning and health preparedness on a sustained basis.

Equivalent Potential Temperature Variability over Chennai during 2018-2023: A Spectral and Wavelet Analysis

2026-10-06T10:42:19+00:00

Background & Aim: Equivalent potential temperature (θe) integrates atmospheric temperature and moisture and is useful for examining thermodynamic variability in coastal environments. This study investigates the spectral characteristics and dominant periodicities of equivalent temperature over Chennai, a coastal station on the southeast coast of India, during 2018-2023, and to identify periodic variations associated with synoptic-scale and planetary-scale atmospheric processes.

Study Design: The study is based on the spectral analysis of equivalent temperature time-series data using the Fast Fourier Transform technique.

Place and Duration of Study: Chennai, on the southeast coast of India, during the six-year period from January 2018 to December 2023.

Methodology: Both local mechanisms and large-scale atmospheric disturbances affect atmospheric thermodynamic variability over coastal regions. This study uses radiosonde records from 2018 to 2023 to examine the temporal variability of equivalent potential temperature (θe) over Chennai, a tropical coastal region influenced by the Indian monsoon system and the Bay of Bengal. Fast Fourier Transform (FFT) and continuous wavelet transform (CWT) methods were used to analyse seasonal θe time series. Prior to spectral analysis, the time series underwent the necessary preprocessing; wavelet analysis was utilised to investigate the temporal variability and persistence of the main periodicities, while FFT was utilised to identify them. In addition to longer-period variability observed in some seasons and years, the study revealed significant short-period variability, especially in the roughly 2–6-day range. These periodic patterns indicate recurring thermodynamic variability in the coastal atmosphere above Chennai. The results provide observational evidence of temporal change in θe and may improve understanding of intraseasonal and synoptic atmospheric variability over coastal South India. The results are interpreted within the constraints of the six-year, single-station observational record.

Results: Over Chennai, the spectral analysis showed noticeable shorter-period oscillations, with dominant periodicities often falling between two and six days. These frequent variations at the synoptic scale show how convective disturbances and transient weather systems affect the thermodynamic state of the coastal atmosphere. Additionally, the spectral features show how the strength of the identified oscillations varies over time across seasons and years.

Conclusion: The findings show clear periodic variability in equivalent temperature over Chennai, with short-period synoptic-scale oscillations contributing significantly. Fast Fourier Transform analysis provides an efficient method for identifying these atmospheric variations and improving understanding of coastal thermodynamic variability. The results could help in evaluating atmospheric instability, monsoon variability, and related weather disturbances over India's southeast coast.

Net Primary Productivity Trends in Uganda (2001–2024): Regional Divergence, Climate Associations and Land-cover Diagnostics

2026-10-06T11:23:18+00:00

Net primary productivity (NPP) integrates the carbon uptake of terrestrial vegetation with the biomass available to agriculture and pastoralism, yet its recent trajectory across Uganda has not been resolved at the scale at which land is managed. We analysed the complete MODIS MOD17 record (2001–2024) for Uganda and its nine agro-ecological zones, together with satellite precipitation, reanalysis meteorology, land cover and burned area, in a zone-resolved assessment of national productivity dynamics. Trends were estimated with the Theil–Sen slope and an autocorrelation-corrected Mann–Kendall test, and were accepted as supported only where confirmed by a circular block bootstrap, with false discovery rate control throughout. National NPP increased by 15.2% (6.22 g C m⁻² yr⁻¹ per year, p < 0.001), with 65.0% of the classified area showing a significant increase, compared with 2.1% showing a decrease. This aggregate concealed marked divergence: the Mid-Northern and West Nile zones gained 31.1% and 30.9%, the Eastern Highlands was the only zone with a negative slope, and supported seasonal increases were confined to the October–December short rains. No climate variable was associated with national productivity; significant coupling was confined to the semi-arid North Eastern Dry Land, where soil moisture explained 69.0% of interannual variance. Matched land-cover transition attribution showed that cropland expansion was associated with productivity gains in the Mid-Northern zone but losses elsewhere, while the two most cropland-saturated zones contained too few eligible transition pixels for comparison. A parameter diagnostic indicated that the leading-zone gains were not primarily an artefact of the algorithm's land cover parameterisation. Uganda's productivity gains are thus concentrated where cultivation is still expanding, while intensively cultivated zones stagnate or decline, a pattern invisible to national aggregate reporting of the kind used for SDG indicator 15.3.1.

Studies on the Effect of Elevated Temperature and CO2 on Yield of Maize Crop under Raipur Condition

2026-10-08T13:01:28+00:00

Climate-driven changes in temperature and atmospheric CO₂ may alter maize productivity, and their combined effects can differ among cultivars and sowing environments. This study used the CERES-Maize model within DSSAT to assess yield responses of NK-30, NK-7328 and NK-6110 under Raipur conditions. The model was calibrated with 2022–23 crop, weather, soil and management data and validated with 2023–24 data. Grain yield was simulated for three sowing environments (D1, D2 and D3) under the current condition, elevated CO₂ concentrations of 450, 500 and 550 ppm, temperature increases of 0.5, 1.0 and 1.5°C, and corresponding combined CO₂-temperature scenarios. Root mean square error and percentage error were used to characterise differences between the present and scenario simulations. In the CO₂-only simulations, grain yield increased across cultivar–environment combinations, with tabulated changes ranging from about 2.1% to 10.2%. In contrast, temperature-only simulations showed yield reductions ranging from 2.19% to 10.61%. Under combined elevated CO₂ and temperature scenarios, yield remained below the present simulated values, with reductions ranging from 1.17% to 7.62%, indicating that the positive CO₂ response only partly offset the simulated temperature penalty. Responses varied among cultivars and sowing environments. The findings demonstrate the value of locally calibrated crop simulation for examining cultivar-specific maize yield responses to incremental climatic changes under Raipur conditions.

Spatial Variability and Geostatistical Mapping of DTPA-Extractable Cadmium in Surface Soils of Varanasi District, Uttar Pradesh, India

2026-10-09T10:33:14+00:00

Background: Cadmium (Cd) availability in agricultural soils can show strong local variation, making district-scale averages insufficient for identifying areas of concern.

Aims: To describe the spatial variability of DTPA-extractable cadmium (DTPA-Cd) in surface soils of Varanasi district, map it by ordinary kriging and assess the uncertainty of the map.

Study Design: Geo-referenced field survey with geostatistical analysis.

Place and Duration of Study: Agricultural soils of Varanasi district, Uttar Pradesh, India, sampled between April and May 2026; laboratory analysis was conducted at the Department of Soil Science & Agricultural Chemistry, Institute of Agricultural Sciences, Banaras Hindu University, India.

Methodology: Ninety-eight surface soil samples (0 to 15 cm) were collected with GPS coordinates and extracted with DTPA. Data were ln-transformed, and spherical, exponential and Gaussian models were fitted to the experimental semivariogram. Ordinary kriging (OK) and inverse distance weighting (IDW) were compared by leave-one-out cross-validation, and the OK prediction and kriging variance were mapped on a 250 m grid.

Results: DTPA-Cd ranged from 0.020 to 6.154 mg kg⁻¹ (mean 0.139, median 0.065 mg kg⁻¹), with a coefficient of variation of 441.9%; 15.3% of samples exceeded 0.1 mg kg⁻¹. The Gaussian model gave the best fit, with a nugget/sill ratio of 42.3% (moderate spatial dependence) and a range parameter of 18.0 km. OK performed slightly better than IDW (RMSE values of 0.616 and 0.619, respectively, on the ln scale), but both explained only 11 to 12% of the variation. Predicted DTPA-Cd ranged from 0.043 to 0.346 mg kg⁻¹, with the highest quartile in the central and eastern parts of the district. Kriging variance was lowest in densely sampled areas and highest in the sparsely sampled centre and along the boundary.

Conclusion: Available Cd in the district is generally low but includes isolated high values. The map shows broad regional tendencies, and the extent of the high class depends strongly on a single extreme sample, which needs field verification and denser sampling.

Root Growth Development and Nutrients Distribution Pattern of Tomato Crop under Drip and Flood Irrigation

2026-10-10T07:07:32+00:00

Root growth development and nutrient distribution are important parameters for optimising the use of inputs such as water and fertiliser. This study compared drip and flood irrigation to determine their effects on tomato root development and the spatial distribution of nutrients. The study assessed the vertical and horizontal distribution of roots and the movement of nutrients in both vertical and lateral directions under drip- and flood-irrigated conditions. The number of roots under both irrigation methods decreased with increasing soil depth and extended horizontally to 30 cm along the plant and 27 cm across the plant under drip irrigation, and to 59 cm and 60 cm, respectively, under flood irrigation. Under drip irrigation, root intensity was higher at a soil depth of 0-20 cm (0.252), whereas under flood irrigation, root density was 0.197 and the number of roots declined progressively with increasing soil depth, with few roots present below 40 cm. Root distribution in the upper soil layer was greater under drip irrigation than under flood irrigation. Most available nitrates were found in the upper soil layer under drip irrigation compared with flood irrigation. Maximum nitrogen, phosphorus and potassium contents under drip irrigation were 229.6 kg ha^-1 at 20-30 cm, 201.08 kg ha^-1 at 0-10 cm and 231 kg ha^-1 at 0-10 cm, respectively. Under flood irrigation, the corresponding values were 277.9 kg ha^-1 at 40-50 cm, 209.03 kg ha^-1 at 0-10 cm and 264 kg ha^-1 at 20-30 cm, respectively. The peak nitrogen concentration of 277.9 kg ha^-1 at 40-50 cm indicated greater nitrate leaching under flood irrigation than under drip irrigation.

Influence of Long-term Fertilization on Productivity and Organic Carbon under Rice-rice System in Inceptisols of Eastern India

2026-10-13T11:00:11+00:00

A field experiment was conducted for eighteen consecutive years (2005-06 to 2021-22) at the Central Farm, OUAT, Bhubaneswar, Odisha, under AICRP on LTFE to assess productivity and soil organic carbon fractions in a rice-rice cropping system under long-term fertilisation. Soil samples were collected from two depths (0-0.15 m and 0.15-0.3 m) under different nutrient management treatments [T₁: control, T₂: 100% N, T₃: 100% NPK, T₄: 150% NPK, T₅: 100% NPK along with FYM, T₆: 100% NPK along with FYM + Lime, T₇: 100% NPK along with Boron + Zinc, T₈: 100% NPK + Sulphur + Zinc] in a randomised block design (RBD) with three replications. Results revealed significant differences in rice grain and straw yields among the treatment combinations, with grain yield ranging from 1.69 to 5.19 t ha^-1. Application of 100% NPK along with FYM and lime produced the highest grain and straw yields of rice. The contributions of different soil organic carbon pools (VLC, LC, LLC and NLC) to TOC were 27.7%, 24.6%, 27.0%, and 20.8% at 0–0.15 m, and 19.5%, 22.8%, 32.4%, and 25.0% at 0.15–0.30 m soil depth, respectively. The carbon pool index (CPI), lability index (LI), carbon management index (CMI), and carbon sequestration (CS) were highest in the treatment receiving integrated nutrient sources. Judicious application of NPK fertilisers and organic sources (FYM), alone or in conjunction with lime, is necessary for maintaining soil organic carbon fractions and nutrient turnover to ensure sustainable crop productivity in a long-term rice-rice cropping system.

Optimizing Pre-sowing Seed Treatments and Growing Media for Enhancement of Germination Attributes of Chironji [Buchanania cochinchinensis (Lour.) M. R. Almeida]

2026-10-14T11:18:12+00:00

This study examined the effects of pre-sowing seed treatments and growing media on the germination performance of Buchanania cochinchinensis (Lour.) M. R. Almeida at the College of Forestry, Navsari Agricultural University, Gujarat. The experiment was laid out in a factorial completely randomised design (FCRD) comprising sixteen treatment combinations across two factors, including four pre-sowing seed treatments viz., S₁: Control, S₂: GA₃ @ 200 ppm (24 h), S₃: Water soaking (24 h) and S₄: Alternate wetting (24 h) & drying (12 h), and four growing media viz., M₁: Soil (control), M₂: Soil + Sand (2:1), M₃: Soil + Sand + VC (2:1:1) and M₄: Soil + VC (4:1). Each treatment was replicated three times, and the seeds were sown directly into polybags. The seed treatment with GA₃ @ 200 ppm for 24 h was found to be the most effective, while Soil + Sand (2:1) was identified as the best growing medium. The interaction of GA₃ @ 200 ppm for 24 h with Soil + Sand (2:1) significantly improved the germination parameters, resulting in earlier germination (9.33 days), shorter germination period (19.33 days), lower time to 50 per cent final germination (13.00 days), and reduced mean germination time (13.52 days). It also recorded the maximum germination percentage (98.33%), mean daily germination (5.09), peak value (1.54), germination value (7.83), and germination rate index (1.52). These findings indicate that GA₃ @ 200 ppm for 24 h combined with soil + sand (2:1) has potential for improving Chironji germination under the nursery conditions.

Spatio-Temporal Dynamics of Groundwater Levels under Climatic Variability in North Eastern Karnataka, India

2026-10-14T13:10:22+00:00

The study assessed temporal and spatial changes in groundwater depth and examined the relationship between groundwater conditions and climatic variables in North Eastern Karnataka (NEK). The study covered six districts, namely Bidar, Kalaburagi, Yadgir, Raichur, Koppal and erstwhile Ballari, from 2015-16 to 2024-25. Groundwater depth data were obtained from Central Ground Water Board observation borewells, while rainfall, relative humidity and temperature data were collected from relevant meteorological sources. Descriptive statistics, compound annual growth rate (CAGR), coefficient of variation, the Mann-Kendall trend test and Sen's slope estimator were employed to assess spatial and temporal variability. Partial correlation analysis was used to examine associations between groundwater depth and climatic variables, while ordinary least squares regression was employed to quantify their influence. The results revealed considerable spatial and temporal variation in groundwater conditions across NEK, with mean groundwater depth ranging from 5.52 m bgl in Yadgir to 14.14 m bgl in Bidar and a regional mean of 8.41 m bgl. Groundwater depth became shallower in Bidar, Raichur, Koppal and Ballari, as indicated by negative growth rates, whereas Kalaburagi and Yadgir showed an increase in groundwater depth, indicating deeper groundwater conditions. Trend analysis also showed significant shallowing of groundwater depth in Bidar, Kalaburagi, Ballari and the NEK region. Higher rainfall and relative humidity were associated with shallower groundwater conditions, whereas higher maximum and minimum temperatures were associated with deeper groundwater conditions. Regression analysis confirmed significant effects of all four climatic variables, which jointly explained 69 per cent of the variation in groundwater depth. The study highlighted the need for location-specific and climate-responsive groundwater management, improved irrigation efficiency, artificial recharge and sustainable groundwater-use practices in NEK.

Hydro-chemical Characterisation and WQI-based Assessment of Groundwater Quality for Irrigation in Chirang District, Assam, India

2026-10-15T12:44:04+00:00

Groundwater is a vital resource for agricultural use, provided that its quality remains within permissible limits. This study evaluates groundwater quality for irrigation suitability in Chirang district, Assam using the Water Quality Index (WQI). Groundwater samples were collected from fifteen locations from open wells and tube wells across the district. In each season, three samples were collected from each location, and their mean values for 2022–2023 were used to calculate the seasonal WQI for each location. Fourteen physicochemical parameters were analysed seasonally and location-wise to compute the WQI. The results revealed that during the pre-monsoon season, 80% of samples were classified as moderate quality and 20% as poor quality. During the monsoon season, 93.3% of samples were of good quality, while 6.7% were of moderate quality. During the post-monsoon season, 46.7% of the samples were classified as good quality and 53.3% as moderate quality. The hydro-chemical data for samples plotted on Piper trilinear diagrams across the three seasons indicated that groundwater was primarily characterised by mixed alkaline-earth chemistry, with most samples belonging to the Ca–Mg–Cl water type and corresponding to the Ca–Mg–Cl–SO₄ hydro-chemical facies. The overall quality of groundwater indicates its suitability for agricultural irrigation.

Mapping and Spatial Analysis of Waste-Dumping Sites in the Tilé Watershed, N’Zérékoré, Guinea: A GIS-based Contribution to Sustainable Urban Waste Management

2026-10-16T08:23:55+00:00

Background : Inadequate solid-waste management poses a serious environmental and public-health challenge in many African cities. In N’Zérékoré, the problem is particularly visible in the Tilé watershed, where informal waste-dumping sites occur close to homes, roads, and the watercourse.

Aim : This study mapped and characterised dumping sites in the Tilé watershed, N’Zérékoré, Guinea, and examined their spatial distribution to inform local solid-waste management planning.

Methods: A systematic inventory was conducted from 6 May to 17 June 2026 across nine neighbourhoods. Active dumping sites were georeferenced using a Garmin 65 GPS receiver, and site boundaries were digitised and analysed in QGIS 3.44.9. Site areas and proximity to dwellings, roads, and the Tilé watercourse were assessed. Kernel density estimation and Global Moran’s I were used to identify concentrations and evaluate spatial clustering.

Results: The survey identified 199 active dumping sites. Of these, 120 (60.3%) were small, 54 (27.1%) were medium-sized, and 25 (12.6%) were large. A total of 170 sites (85.4%) were within 50 m of dwellings, 128 (64.3%) within 50 m of roads, and 50 (25.1%) within 50 m of the watercourse. Five areas of relatively high concentration were identified in Dorota 1, Wessoua, Gbanghana, Mohomou, and Nakoyakpala. Global Moran’s I indicated statistically significant positive spatial autocorrelation (I = 0.42; p = 0.001).

Conclusion: Dumping sites were unevenly distributed across the watershed, with substantial proximity to residential areas and the watercourse. These findings provide a spatial basis for prioritising collection services, identifying suitable designated collection points, and monitoring affected neighbourhoods.

Productivity, Competitive Interactions and Soil Responses of Maize, Sorghum and Cowpea under Different Intercropping Systems in Red and Lateritic Soils of West Bengal, India

2026-10-16T08:34:56+00:00

Intercropping can improve land-use efficiency and overall productivity through complementary resource use, although competition among component crops may affect individual crop performance. A field experiment was conducted during December–April 2025 under red and lateritic soil conditions of Paschim Medinipur, West Bengal, to evaluate the productivity, competitive interactions, economic performance and post-harvest soil properties of maize, sorghum and cowpea grown as sole and intercrop systems. Seven treatments comprising sole maize (T₁), sole sorghum (T₂), sole cowpea (T₃), maize + cowpea (T₄), sorghum + cowpea (T₅), maize + sorghum (T₆) and maize + sorghum + cowpea (T₇) were evaluated in a randomized block design with three replications. Maize + cowpea (T₄) produced the highest maize growth and maintained a grain yield of 6.23 t ha⁻¹ compared with 5.97 t ha⁻¹ in sole maize. Sorghum + cowpea (T₅) significantly increased sorghum grain yield to 3.90 t ha⁻¹ compared with 3.68 t ha⁻¹ in sole sorghum. Cowpea yield declined under intercropping, with the greatest reduction in T₇. All intercrop systems recorded calculated land equivalent ratios greater than unity, with the highest value in T₇ (2.52). T₇ also recorded the highest reported maize equivalent yield (18.87 t ha⁻¹), gross return (₹362,138.5 ha⁻¹) and net return (₹250,312.5 ha⁻¹), whereas T₅ recorded the highest reported benefit:cost ratio (2.77). Cowpea-containing systems generally maintained higher post-harvest soil organic carbon, total nitrogen and available nitrogen. Overall, maize + cowpea (T₄), sorghum + cowpea (T₅) and the three-component system (T₇) showed distinct advantages in component-crop and system-level performance.

Assessment of Reservoir Filling Efficiency of Medium Irrigation Projects in Telangana State, India for Enhancing the Water Use Efficiency

2026-10-16T13:11:51+00:00

Reservoirs play an important role in regulating water availability for irrigation, particularly under variable hydrological conditions. The study assessed annual inflow variability, major water-balance components and reservoir filling efficiency of five selected medium irrigation projects in Telangana from 2009–10 to 2019–20. Secondary data on inflows, outflows, withdrawals, spillages and reservoir storage were collected from the respective project offices. Evaporation and seepage losses were estimated using water-spread area, evaporation data and prescribed seepage rates. Reservoir filling efficiency was calculated based on the maximum annual live storage attained relative to the designed live storage capacity. The results showed considerable temporal and spatial variation in annual inflows, with 2013–14 recording relatively high inflows across all five selected projects. Taliperu recorded the highest average reservoir filling efficiency of 97.11% with the lowest variability (CV 1.0%), followed by Vattivagu (95.31%), Sathnala (94.47%), Musi (89.11%) and Peddavagu (84.72%). Musi exhibited the highest variability (CV 11.2%), mainly due to exceptionally low efficiencies during 2014–15 and 2015–16. Higher inflows were associated with increased spillage, particularly in Taliperu, while seepage and evaporation contributed to continuous water losses. The findings indicate that reservoir filling efficiency is governed by the combined effects of inflow magnitude and distribution, storage conditions, reservoir siltation and water losses. Assessment of filling efficiency over multiple years provides useful information for evaluating storage utilisation, reservoir performance and overall water-use efficiency of the irrigation projects. Regular monitoring, structural maintenance, catchment treatment and improved water-level monitoring can support effective reservoir operation and better utilization of available water resources and thereby enhance water-use efficiency of the irrigation projects.

Mapping of Potential Aquifer Recharge Zones in the Fractured Aquifers of the Agboville Department in Southeastern Côte d’Ivoire

2026-10-17T05:28:36+00:00

Groundwater management in the Agboville department requires identification of areas that are favourable to aquifer recharge. The objective of this study was to identify potential aquifer recharge zones in the Agboville department to improve water-resource management and support sustainable development. Mapping these zones involved identifying six parameters (land use, soil types, weathering layer thickness, slope, induced permeability, and drainage density) that influence recharge and preparing a thematic map for each parameter. The parameters were then weighted according to their relative importance in the recharge process using Saaty's Analytical Hierarchy Process (AHP) method. The thematic maps were subsequently combined within a GIS to produce a map of potential aquifer recharge zones for the department. Five recharge-suitability classes were identified: poor (4%), marginal (17%), moderate (28%), good (31%), and very good (19%). The map indicates that favourable recharge zones (moderate, good, and very good) occupy 78% of the study area and occur across almost the entire department. These zones are generally characterised by gentle slopes (<5%), low drainage density (<1.52 km/km²), and a weathering-layer thickness of 3-30 m, which favour infiltration. Conversely, low-recharge zones cover 21% of the department's surface area and are located primarily in urban areas and along watercourses. Land use was identified as the predominant factor influencing recharge in this crystalline-basement zone. The map may therefore serve as a decision-support tool for departmental planning and groundwater-protection activities.

Contribution of Principal Component Analysis to the Hydrochemical Characterization of Groundwater in the Department of Kantché, Southwestern Zinder Region (Niger)

2026-10-18T04:42:07+00:00

The Kantché Department in southwestern Zinder, Niger, depends on groundwater for domestic and socio-economic activities, but the factors affecting its chemical composition remain insufficiently characterised. This study investigated groundwater hydrochemistry and the principal processes associated with mineralisation using physicochemical measurements, a Piper diagram and principal component analysis (PCA). Groundwater samples were obtained from 25 water points, and PCA was applied to 11 physicochemical variables. The measured pH ranged from 4.6 to 7.76, with a mean of approximately 6.2, while electrical conductivity varied from 23 to 404 µS/cm, with a mean of 100.92 µS/cm. These results indicate generally low mineralisation and a tendency towards slightly acidic conditions. The predominant hydrochemical facies was calcium–magnesium bicarbonate. The first three principal components explained 47.58%, 17.32% and 11.91% of the variance, respectively, accounting for 76.81% cumulatively. Electrical conductivity was positively associated with bicarbonate, calcium and sulphate, whereas ferric iron showed comparatively weak correlations with most parameters. The PCA projections differentiated groups of physicochemical variables and water points with similar hydrochemical characteristics. The observed associations suggest that water–rock interactions, including weathering and mineral hydrolysis, are important influences on groundwater composition, alongside possible surface-derived inputs and redox-related processes. The findings provide a hydrochemical basis for interpreting groundwater variability in Kantché and can inform subsequent assessment and protection of this resource.

Forest-savanna Boundary Dynamics in a Context of Climate Variability: The Case of the Belier Region in Côte D’ivoire

2026-10-18T04:51:41+00:00

Climate variability may influence vegetation dynamics at the forest-savanna boundary, but the temporal relationship between rainfall variability and land-cover change in the Belier region remains insufficiently resolved. This study assessed rainfall variability and forest-savanna boundary dynamics in the Belier region of Côte d’Ivoire. Mean annual rainfall data were analysed for the 1981–2020 period using the rainfall anomaly index, while Landsat imagery for 1988, 2000, and 2020 was used to map land-cover change through supervised classification. The climate analysis indicated an overall decline in rainfall, with deficits of approximately 16%. The decline was particularly pronounced during the 1991–2008 period, when rainfall anomaly indices shifted predominantly towards negative values. From 2009 onwards, precipitation showed a slight recovery. Land-cover analysis revealed forest degradation in favour of savanna between 1988 and 2000, followed by forest regeneration at the expense of savanna between 2000 and 2020. The correlation analysis indicated a strong positive relationship between rainfall and forest area and a strong negative relationship between rainfall and savanna area. These results suggest that the direction of forest-savanna boundary change broadly corresponded with rainfall trends during the study period. However, anthropogenic pressures, reforestation and conservation measures, and plantation fallowing may also have contributed to the observed vegetation dynamics. The findings therefore support a cautious interpretation of forest-savanna changes as outcomes of interacting climatic and human influences.

Impact of Climate Change on Biological Systems in the Agro-Ecological Zone 14 of Uttarakhand, India

2026-10-22T10:36:57+00:00

Uttarakhand has a predominantly rural population, with agriculture serving as a key livelihood for many people. Farming is predominantly smallholder-based, rainfed, and subsistence-oriented, especially in hilly areas where landholdings are fragmented and agricultural productivity is low because of challenging terrain, limited irrigation, and poor market access. The state faces challenges including climate change, migration, small landholdings, and inadequate infrastructure, which affect agricultural productivity and rural livelihoods.

Climate change directly threatens agricultural productivity. Rising temperatures can diminish crop yields and affect vegetable quality and shelf-life. Unpredictable rainfall and droughts may induce water stress, whereas excessive rainfall can lead to crop diseases and post-harvest losses.

The present study aims to assess the exposure of biological systems to climate change in AEZ 14 and to examine changes in climate-related conditions and their impacts on biological systems over the past ten years. The study was carried out in the Almora and Nainital districts of AEZ 14 in Uttarakhand.

Data from the last decade in AEZ 14 revealed increased incidences of diseases and pest attacks. In Almora, 26.67% of respondents reported increased crop yield, compared with 15% in Nainital, whereas 33.33% in Almora and 54.17% in Nainital reported low yield. Additionally, 71.67% of respondents in Almora and 29.17% in Nainital reported increased wildlife attacks. The use of chemicals in crop cultivation was higher in Almora (45.33%) than in Nainital (25%). In AEZ 14, households reported substantial changes in climatic conditions over the last decade.

Tracking the Emission Levels of Greenhouse Gases from Agricultural Activities in Nigeria for Global Climate Action

2026-10-23T06:57:59+00:00

Greenhouse gas (GHG) emissions associated with livestock, crop production and land-use change are important considerations for climate action in Nigeria. This study assessed concentrations of methane (CH₄), nitrous oxide (N₂O) and carbon dioxide (CO₂) at selected livestock and farmland sites across the country's six geopolitical zones. Field measurements were undertaken at 25 sites per zone, while annual emissions were estimated using an IPCC Tier 1 approach with activity data and specified emission factors. Livestock-site concentrations ranged from 1.90 to 3.67 ppm for CH₄, approximately 0.35 to 0.39 ppm for N₂O and 340.3 to 390.1 ppm for CO₂. Corresponding farmland concentrations ranged from 80.44 to 157.2 ppm, 0.293 to 0.330 ppm and 555.21 to 775.31 ppm, respectively. An illustrative emissions inventory based on 150 livestock heads and 100 ha of farmland yielded a total of 67,738,300.75 kg CO₂e/year. Within this estimate, soil-carbon losses associated with land-use change accounted for 67,100,000 kg CO₂e/year, exceeding the contributions of rice cultivation, livestock and nitrogen-related activities. A projection scenario considered annual livestock growth of 2% with farmland area held constant through 2030. The findings identify soil-carbon conservation, improved manure management, more efficient fertiliser application and alternative water management in rice cultivation as relevant mitigation considerations. Further validation of activity data, emission estimates and projections is required before extrapolating these results to national agricultural emissions.

Assessing Heatwave Severity and Trends in the Southwest Coast Region of Bangladesh Using Heat Index

2026-10-23T10:31:47+00:00

Background and Aims: Bangladesh is among the countries highly susceptible to heatwaves and heat stress. This study aims to analyse the severity and growing intensity of heatwaves in the southwest coast region of Bangladesh. It investigates the potential increase in the frequency of seasonal heatwaves and of moderate and severe heatwaves in the southwest coast region.

Place and Duration of Study: The southwest coast region of Bangladesh, from 1981 to 2020.

Methodology: Heat Index (HI) was calculated from air temperature and humidity data using Steadman’s formula for apparent temperature. The Bangladesh Meteorological Department’s standard definition and classification of heatwaves were applied to the HI values, and temporal trends were detected using the Mann-Kendall test. Intensification of seasonal, moderate and severe heatwaves was measured using linear regression, the coefficient of determination, and statistical significance tests.

Results: The results show statistically significant intensification of heatwave patterns across the region (P = .01 in Bhola; P < .001 in Khulna, Barishal and Satkhira; τ = 0.28–0.54). The temporal trend of heatwaves indicates that Khulna was the most affected by heat stress. The intensification of moderate and severe heatwaves is more noticeable after 2000 (April-September). However, severe heatwaves intensified most during the last decade (post-2011). The monsoon season experiences the most heatwaves, particularly in Barishal (slope = 1.27, R² = 0.65). The strongest increasing trend in moderate heatwaves was also observed in Barishal (slope = 1.11, P-value < .001), followed by Khulna (slope = 0.91, P-value < .001). Khulna showed the strongest rising trend in severe heatwaves (slope = 0.75, P-value < .001). Most heatwaves in the southwest coast region lasted 3 days, although longer events were also observed (IQR = 5-7).

Conclusion: The findings show spatial variability in heatwave behaviour, underlining the need for more localised adaptive measures to cope with increasing heat. To understand nationwide heatwave risks, future studies should cover a broader region and include additional socioeconomic indicators to assess the impact of heatwave occurrences on the local population.

Seasonal Air Pollution Patterns in an Assam Monitoring Dataset for 2024

2026-10-24T08:56:41+00:00

Aims: To describe seasonal variation in four ambient air pollutants and examine pollutant covariance and seasonal discrimination in a compiled 2024 Assam monitoring dataset.

Study Design: A retrospective exploratory analysis of monthly station-level environmental monitoring observations.

Place and Duration of Study: Thirty monitoring stations across 13 locations in Assam, January–December 2024.

Methodology: The analysis included 360 complete station-month observations of sulphur dioxide, nitrogen dioxide, PM₁₀ and PM₂.₅. Descriptive statistics characterised pollutant distributions. Principal axis factoring examined the correlation structure, and Friedman tests compared seasonal means within stations. Linear discriminant analysis used three pollutants with equal seasonal priors. Classification was assessed in-sample and using leave-one-record-out and leave-one-station-out validation.

Results: The Kaiser–Meyer–Olkin measure was 0.663 and Bartlett’s statistic was χ²(6) = 1645.66. A single factor accounted for 62.73% of total standardised variance, with particulate loadings of 0.967 and 0.954. Mean PM₁₀ and PM₂.₅ concentrations in winter were 114.74 and 55.41 µg/m³, respectively, compared with 47.39 and 22.67 µg/m³ during monsoon. Friedman statistics ranged from 34.60 to 84.28 (all P < .001). The first discriminant function accounted for 97.14% of between-group discrimination. Classification accuracy was 52.5% in-sample, 48.9% under leave-one-record-out validation and 50.8% under leave-one-station-out validation. Equality of seasonal covariance matrices was rejected.

Conclusion: Particulate concentrations displayed a consistent winter–monsoon contrast, but seasonal pollutant profiles overlapped substantially. Findings describe this compiled network-year and require source-record verification and multi-year validation before operational application.

Impact of Climate Variability on Cereal Crops in Mali between 2010 and 2019: Case of the Agricultural Zone of Niono

2026-10-24T09:03:30+00:00

Climate variability may affect cereal production through changes in rainfall and temperature patterns. This study assessed the relationship between climate variability and cereal yields in the agricultural zone of Niono, Mali, during 2010–2019, focusing on rice, millet and sorghum. Climate data comprised annual averages of temperature, rainfall and relative humidity obtained from the meteorological station of the Institute of Rural Economy in Niono, while agricultural yield data were provided by the Regional Directorate of Agriculture of Ségou. Rainfall variability was characterised using the Standardized Precipitation Index, thermal anomalies were assessed using the Lamb temperature index, and relationships between climatic variables and crop yields were examined using Spearman correlation coefficients. Over the decade, mean rainfall, temperature and relative humidity were 602.75 mm, 28.75°C and 54.27%, respectively. Rainfall varied irregularly, with 2015 recording the highest rainfall and 2014 a marked deficit, while temperature showed a slight upward tendency. Most correlations between climatic parameters and cereal yields were weak. The coefficients for rice were −0.12, −0.48 and −0.03 for rainfall, temperature and humidity, respectively; corresponding values were 0.15, 0.23 and 0.64 for millet and 0.12, 0.18 and −0.22 for sorghum. These results indicate that climatic variables alone do not explain the observed variation in cereal yields during the study period, and other agronomic and technical factors may also contribute.

Evaluation of the Fertilizing and Energy Potential of Biochar Produced from Coconut Shells by Pyrolysis in the Municipalities of Porto-Novo and Comè-Grand-Popo, Southern Benin

2026-10-24T12:03:27+00:00

Biochar produced through lignocellulosic-biomass pyrolysis may improve tropical soil fertility and provide feedstock for charcoal briquettes. This study characterised coconut-shell biochars produced with a locally fabricated pyrolyser under the Agri-resilience project in Porto-Novo and Comè-Grand-Popo, Benin, between December 2025 and February 2026. Analyses conducted at the 2A2S2E laboratory covered major elements (N, P, K, Ca, Mg and Na), trace elements (Zn, Mn, Cu and Fe), organic matter, organic carbon, ash, moisture, dry matter, pH and particle-size distribution. Results were compared with International Biochar Initiative and European Biochar Certificate criteria, and measurement reproducibility was assessed using coefficients of variation. Both biochars broadly complied with the selected IBI criteria for most valid parameters. Porto-Novo biochar contained more than 50% organic carbon and approximately 86.5% organic matter, indicating potential suitability as an agricultural amendment. Comè biochar had a more alkaline pH and higher calcium content, but its measured ash content of 7.9–11.5% may constrain direct energy use. Reproducibility was satisfactory for most parameters, although Fe, Na and Ca exceeded the 5% variability threshold. Improved production control, sample homogenisation and laboratory mass-balance verification are required before definitive use-specific recommendations are made.

Influence of Pre-Emergence Herbicide Mixtures on Growth, Yield and Soil Fertility of Direct-Seeded Rice (Oryza sativa L.)

2026-10-24T12:52:15+00:00

Direct-seeded rice is vulnerable to early-season weed competition, making effective pre-emergence weed management important for crop growth, grain yield and soil nutrient status. A field study was conducted at the College of Agriculture, V. C. Farm, Mandya, Karnataka, during the Kharif season of 2021. The experiment was laid out in a randomised block design comprising nine treatments, viz.: T1: Pretilachlor 30% + pyrazosulfuron ethyl 0.75% WG @ 1500, g ha^-1 at 0-3 DAS, T2: Pretilachlor 30% + pyrazosulfuron ethyl 0.75% WG @ 2000, g ha^-1 at 0-3 DAS, T3: Pretilachlor 30% + pyrazosulfuron ethyl 0.75% WG @ 2500, g ha^-1 at 0-3 DAS, T4: Pyrazosulfuron ethyl 10% WP @ 250 g ha^-1 at 3-5 DAS, T5: pretilachlor 50% EC @ 1500 ml ha^-1 at 0-5 DAS, T6: Pretilachlor 30% EC + 10% safener @ 1000 ml ha^-1 at 3-5 DAS, T7: hand weeding (20 & 40 DAS), T8: weedy check (control), and T9: weed-free check. The experiment was replicated three times on sandy loam soil to investigate the effect of various pre-emergence herbicides on growth attributes such as plant height, leaf area, tiller count and dry matter production in direct-seeded rice. The results indicated that, among the chemical weed management treatments, pretilachlor 30% + pyrazosulfuron ethyl 0.75% WG @ 2500 (g ha^-1 ) at 0-3 DAS (T3) recorded higher plant height (25.49, 47.11, 72.13 and 78.93 cm), number of tillers per metre row length (72.20, 170.52, 248.17 and 208.30), leaf area per metre row length (1293.70, 3190.9, 7927.0 and 2665 cm² per m row length), total dry matter production per metre row length (6.58, 91.24, 226.35 and 607.60 g per m row length) at 30, 60, 90 DAS and at harvest, respectively. These results were statistically comparable with those of the (T₉) weed-free check and (T₇) hand-weeding treatment at 20 & 40 DAS. The same treatment recorded a higher grain yield (6491 kg ha^-1) and straw yield (9584 kg ha^-1), which were comparable with those under hand weeding and the weed-free check. Post-harvest soil pH, EC and organic carbon were not significantly affected by the weed management practices. However, available N, P₂O₅ and K₂O were significantly influenced by the treatments. The study indicated that pretilachlor 30% + pyrazosulfuron ethyl 0.75% WG @ 2500 g ha^-1 applied at 0-3 DAS was an effective pre-emergence mixture for improving growth and productivity while maintaining favourable post-harvest soil nutrient availability in direct-seeded rice.