Current Research on Geography, Earth Science and Environment Vol. 9

Impact of Open Dumpsite Wastes on Soil Quality in Akwa Ibom State, Nigeria: Implications for Environmental Sustainability and Agriculture

2026-08-03T09:09:02+00:00

Open waste disposal systems have raised significant environmental concerns because of their potential to degrade soil quality. This study assessed the effects of waste dumpsites from auto mechanic (A), abattoir (AB), and paint processing (P) activities on soil quality. A control area (C), with no known waste contamination, was selected for comparison. Soil samples were collected from three depths (0-20, 20-40, and 40-60 cm) at the dumpsites after (waste removal) and at the control site, and were analyzed using standard laboratory methods. Soil quality indicators associated with nutrient availability, namely soil texture, pH, organic carbon (OC), and total exchangeable bases (TEB), as provided by the Harmonized World Soil Database (HWSD), were used for quality assessment. The results showed that waste deposits significantly altered the physicochemical properties of the soils. Particle size distribution analysis indicated that the soils were predominantly sandy, consistent with their coastal plain sand origin. The pH values of the impacted soils increased to 7.36, 7.99, and 6.49 for A, P, and AB, respectively, compared with 4.63 for C, indicating a shift from acidic to near-neutral (AB) and alkaline conditions (A and P). OC levels were significantly higher in A and AB, suggesting organic matter accumulation; however, these elevated levels may not necessarily indicate improved soil fertility because of possible contamination and low-quality organic residues. Positive correlations between measured indicators in waste materials and impacted soils demonstrated the influence of waste composition on soil properties. The study concludes that open dumpsites negatively affect the soils they occupy, reduce soil quality, and pose risks to agricultural and environmental sustainability. Engineered landfills and eco-friendly remediation techniques, such as phytoremediation, are recommended.

WRSI-Based Rainfall Deviation Thresholds for Monitoring Drought-Induced Water Stress in Kharif Pulse Crops

2026-08-03T09:14:22+00:00

Rainfall variability is a major source of water stress in rainfed pulse production during the kharif season. This study evaluated whether rainfall-deviation thresholds derived from the Water Requirement Satisfaction Index (WRSI) could support drought-related crop-condition monitoring in Telangana, India. Blackgram, greengram and redgram were examined at 20 representative locations in Medak, Warangal and Mahabubnagar districts, respectively. Gridded rainfall and maximum and minimum temperature data for 2000–2015, together with soil information, were used in a soil-water-balance framework to estimate rainfall deviation, potential crop evapotranspiration, actual crop evapotranspiration and seasonal WRSI. Rainfall-deviation frequencies were assessed for 2000–2016. Deficit rainfall occurred more frequently at the blackgram locations, whereas normal rainfall was more common at the greengram and redgram locations. WRSI classifications indicated predominantly mediocre crop conditions for blackgram and average-to-good conditions for greengram and redgram. The coefficients of determination for rainfall–WRSI relationships ranged from 0.26 to 0.77 for blackgram, 0.35 to 0.94 for greengram and 0.57 to 0.96 for redgram. Rainfall-deviation thresholds for blackgram were broadly interpretable across the assessed soil conditions, while thresholds for greengram and redgram varied with soil type and depth. The findings indicate that WRSI-based thresholds may assist comparative monitoring of drought-induced water stress when crop characteristics and soil water-holding conditions are considered.

Rainy Season Dynamics of Phosphorus Fractions in Lake Toho Sediments and Surrounding Agricultural Soils

2026-08-03T09:18:09+00:00

Phosphorus enrichment in cultivated soils adjacent to surface waters can increase nutrient transfer and eutrophication risk, especially during rainy periods. This study evaluated the mobility and bioavailability of phosphorus in soils surrounding Lake Toho, southern Benin. Samples were collected from 13 sites and analysed for pH, moisture, organic matter, total phosphorus and operationally defined phosphorus fractions. Soil water pH ranged from 6.25 to 8.30, indicating weakly acidic to weakly basic conditions. Moisture varied from 1% to 38%, while organic matter ranged from 40.30% to 49.70%. Total phosphorus concentrations ranged from 1,049.74 to 28,436.52 µg g⁻¹ and were generally higher in the upper horizons. Phosphorus occurred as labile, iron-bound, aluminium-bound, calcium-bound, organic and residual fractions. Organic and residual phosphorus were the dominant forms overall, whereas labile and other potentially mobile fractions were detected across the sampled horizons. Correlation and principal component analyses indicated relationships among total phosphorus, residual phosphorus, labile phosphorus, organic matter, moisture and pH-related calcium associations. The results suggest that cultivated soils around Lake Toho contain substantial phosphorus stocks influenced by agricultural inputs, parent material and soil properties. During rainfall and runoff events, part of these stocks may be transferred towards the lake. Continued seasonal monitoring and improved nutrient management are therefore needed to reduce potential phosphorus losses while maintaining soil fertility. PCA confirms the consistency of the results and effectively synthesizes the key agronomic and environmental indicators essential for sustainable nutrient management. This analysis structures data variability by highlighting the predominant yield factors.

Conservation and Ecological Dynamics of Juniperus Macropoda in the Himalayas: Current Knowledge, Threats, and Management Imperatives

2026-08-11T10:24:11+00:00

Himalayan juniper woodlands are among the most structurally distinctive yet poorly quantified forest formations of the cold-arid western Himalaya. The taxon most frequently reported regionally as Juniperus macropoda is long-lived, drought tolerant and culturally important, but its conservation assessment is complicated by unstable nomenclature, fragmented distribution records and geographically concentrated ecological research. This critical narrative review evaluates evidence on taxonomic identity, population structure, regeneration, edaphic controls, community ecology, climate sensitivity, human use and management. Literature published from 1948 to 26 May 2026 was identified through accessible scholarly indexes, taxonomic databases, institutional repositories, journal archives and citation searching. The evidence indicates that Himalayan stands cannot be represented by a single demographic narrative. Some populations retain reverse-J size structures and active recruitment, especially at lower or intermediate elevations, whereas others are dominated by mature or overmature trees with few juveniles. Recruitment is constrained by interacting filters: low proportions of viable seed, physiological dormancy, moisture-limited microsites, coarse or nutrient-poor soils, grazing, trampling, lopping, fuelwood extraction and the loss of seed-bearing adults. Reported upslope movement and increased low-density vegetation at one Lahaul site are consistent with climatic influence, but species-specific attribution remains uncertain because remote-sensing signals, land-use history and local topography are confounded. Cultural and subsistence uses increase pressure but also provide social institutions that can support stewardship. The strongest management case is therefore for place-based, taxonomically explicit and socially negotiated conservation rather than uniform exclusion. Priorities include voucher-linked genetic resolution, range-wide mapping, permanent demographic plots, grazing and harvest experiments, provenance-aware seed systems, assisted natural regeneration, protection of microrefugia and community monitoring. Confidence is highest in the diagnosis of severe evidence gaps and site-specific regeneration constraints; confidence is lower in regional forecasts of range shift, carbon storage and population trajectory.

Prior Knowledge as a Condition for AI Mediated Geospatial Learning: An Exploratory Case Study

2026-08-12T09:31:05+00:00

The accelerated adoption of generative artificial intelligence (AI) tools in higher education has outpaced our understanding of the conditions under which they actually support technical learning. This chapter addresses that gap through an exploratory qualitative case study conducted with environmental engineering students at Universidad Santo Tomás (Colombia) during the second academic semester of 2025. The study examines how prior disciplinary knowledge in geographic information systems (GIS) shapes the way students mobilise freely available AI tools, ChatGPT and DeepSeek, when facing an authentic geospatial task: the multitemporal analysis of Lake Tota using the Normalized Difference Water Index (NDWI) in ArcGIS Pro. Drawing on a corpus of queries submitted to the AI tools by two contrasting groups, the study documents a clear pattern. Students without a conceptual baseline produced generic queries, reached the central concept of the task only near the end of their process, could not interpret the model's responses, and abandoned the task amid frustration; none reached a verifiable result. Students with prior GIS training anchored their very first query in the technical concept, recovered from errors within minutes, and most reached verifiable outcomes, although a recurring error in the Landsat band formula revealed the risks of uncritical trust in AI output. Interpreted through the lenses of meaningful learning, AI literacy, and cognitive offloading, the findings suggest that AI amplifies existing disciplinary competence rather than substituting for it, and that the instructor remains decisive in the conceptual scaffolding stage. The chapter contributes a transferable reflection for integrating AI into technical curricula in resource-constrained contexts.

Water Quality of Selected Active Deep Wells in a Local Community: An Initial Assessment

2026-09-01T07:01:30+00:00

Safe groundwater is important for public health and domestic use. This initial assessment evaluated the physicochemical and microbiological quality of six selected active deep wells in San Policarpo, Calbayog City, together with their protective structures, locations, and surrounding conditions. Water samples were collected from six sites and submitted to the Department of Science and Technology laboratory for physicochemical and microbiological analyses. The measured physicochemical parameters included pH, temperature, total hardness, total dissolved solids, salinity, turbidity, conductivity, chloride, nitrite, and total iron. Results showed that all wells had pH values below the stated permissible range. Site 2 met the stated limits for all other measured physicochemical parameters, whereas the remaining sites exceeded one or more limits, particularly for total hardness, total dissolved solids, salinity, turbidity, or conductivity. Chloride, nitrite, and total iron were within the stated limits at all sites. Microbiological testing showed faecal coliform, Escherichia coli, total coliform, and heterotrophic plate counts above the stated permissible levels in all six wells. Most wells were cemented but uncovered, and the sites were located near houses, farms, poultry areas, or vegetation. These findings indicate that the assessed deep-well water should not be used for drinking, cooking, or dishwashing without appropriate treatment. Regular monitoring, appropriate well protection, and water-treatment measures, including coagulation, sedimentation, filtration, and disinfection, are recommended.

Eco-hydrogeochemical Assessment of the Ecologically Sensitive Zeilad Lake (Northeast India) Using Water Quality Index and Multivariate Statistical Analysis

2026-09-04T09:35:00+00:00

An eco-hydrogeochemical assessment was conducted for Zeilad Lake in Manipur, a high-altitude, ecologically sensitive freshwater lake, using water quality indices and multivariate statistical techniques. The findings of the study highlight the need to conserve this pristine lake ecosystem and also advocate minimising human activities such as excessive slash and burn cultivation, deforestation, and changes in land use and land cover patterns, which cumulatively alter the existing lake ecosystem health. The water quality indices classify 78% of the samples as "excellent," 11% as "good," and 11% as "poor" quality water. This is attributed to the release of phosphate from the use of chemical fertilisers and other anthropogenic waste, leading to nutrient enrichment of the lake and causing significant ecological and ecohydrological disturbances to its current status. The hydrogeochemical facies indicated a Cl^--Ca²⁺ water type, suggesting the possibility of anthropogenic as well as brine-related geological influences, with rock-weathering identified as the dominant geochemical process shaping the lake's water chemistry. The bivariate and multivariate statistical analyses identified significant relationships among TDS, EC, and salinity, illustrating the prevalence of both carbonate and non-carbonate hardness as well as the impacts of inorganic pollutants from anthropogenic sources. Irrigation water quality indices indicate that water samples are suitable for irrigation and agricultural use, although slightly elevated magnesium levels were noted in a few water samples.

GIS-Based Healthcare Accessibility and Spatial Inequalities among Older Adults: A Critical Narrative Review

2026-10-05T11:24:11+00:00

Geographic information systems are widely used to identify populations with limited access to healthcare, but spatial proximity does not necessarily represent access to appropriate, affordable and timely care. This distinction is particularly consequential for older adults, whose healthcare requirements, functional abilities, transport resources and support networks vary substantially. This critical narrative review examines how geographic information systems measure healthcare accessibility and how the resulting estimates should be interpreted when assessing inequalities in later life. Targeted searches of openly accessible scholarly indexes, regional sources and citation networks covered literature published from 2000 to 29 July 2026. Foundational methodological studies, age-specific applications and complementary evidence on healthcare utilisation and digital access were critically compared. The synthesis distinguishes potential spatial access, feasible access under individual constraints, realised utilisation and effective care. Floating catchment area methods provide useful representations of the interaction between service capacity, population demand and travel impedance, but their outputs depend on assumptions about competition, catchment boundaries, transport modes and facility eligibility. Evidence from different regions repeatedly identifies peripheral and transport-disadvantaged populations with poorer modelled access, although the relative position of urban centres and service tiers changes with population competition and analytical choices. Associations with utilisation are inconsistent, and observational accessibility maps cannot establish that relocating facilities improves health. Age-only demand measures, incomplete facility registers, residential aggregation and inadequate representation of people unable to travel are persistent threats to validity. Recent high-resolution datasets and mobility-informed models improve analytical possibilities without resolving these problems automatically. An interpretive framework is proposed that separates need, feasible journeys, eligible service capacity, realised care and outcomes rather than combining them into an undifferentiated score. Priorities include independent journey validation, inclusion of homebound populations, uncertainty-aware planning and prospective evaluation of service and transport interventions. Geographic analysis is most defensible as one component of an accountable, person-centred assessment of healthcare equity.