Wet Season Research Articles

Integrating Mixed Livestock Systems to Optimize Forage Utilization and Modify Woody Species Composition in Semi-Arid Communal Rangelands

Communally owned rangelands serve as critical grazing areas for mixed livestock species such as cattle and goats, particularly in the arid and semi-arid regions of Southern Africa. This study aimed to evaluate the nutritional composition and woody species composition of communal rangelands where cattle and goat flocks graze together and to investigate the influence of grazing intensity on vegetation dynamics. Vegetation surveys were conducted across varying grazing intensities to assess species richness, biomass, and dietary preferences, while soil properties were analyzed to determine their interaction with vegetation attributes. Stepwise regression and path analyses were used to explore the relationships between soil characteristics, vegetation structure, and livestock dietary choices. The results revealed that high grazing pressure significantly reduced grass biomass (p = 0.003) and woody species density (p = 0.007) while increasing shrub cover (p = 0.018). Nutritional analysis indicated that goats preferred woody shrubs, which contributed 42.1% of their diet compared to 27.8% for cattle (p = 0.008). Regression analysis further showed that soil organic carbon (p = 0.002) and tree height (p = 0.041) were strong predictors of shrub cover. Seasonal variation significantly affected forage availability and nutritional content, with higher crude protein levels recorded during the wet season (p = 0.007). These findings suggest that grazing management strategies should be tailored to the distinct forage needs of cattle and goats to maintain the productivity and ecological stability of communal rangelands. A holistic approach that considers livestock dietary preferences, vegetation composition, and soil health is essential for sustainable rangeland management in mixed-species grazing systems.

Habitat Assessment of Bocachico (Prochilodus magdalenae) in Ciénaga de Betancí, Colombia, Using a Habitat Suitability Index Model

This study evaluates the habitat of the Bocachico fish (Prochilodus magdalenae) in the Ciénaga de Betancí, Colombia, using a habitat suitability index (HSI) model. Wetlands like the Ciénaga de Betancí are under significant pressure from anthropogenic activities, affecting biodiversity and ecosystem health. The Bocachico, a species of immense cultural and economic importance, faces habitat degradation and fragmentation. Using hydrodynamic and water quality data, a numerical model (EFDC+ Explorer 11.5), and field data collected from multiple sampling campaigns, we assessed habitat suitability based on five key parameters: water temperature, dissolved oxygen, ammonia nitrogen, velocity, and depth. The model results indicated that environmental conditions in the wetland remained relatively stable during the dry season, with an average HSI score of 0.67, where 9% of the wetland area displayed acceptable conditions, and the remaining 91% displayed medium conditions. The wet season, on the other hand, had an average HSI score of 0.64, with 7.2% of the area in the acceptable suitability range, and the remaining 92.8% in the medium category. Variations in HSI were primarily driven by ammonia nitrogen levels, water velocity, and depth. Despite limited fluctuations in the HSI, areas of low suitability were identified, particularly in regions impacted by human activities. These findings have practical implications for conservation strategies, providing valuable insights for the sustainable management and conservation of the Ciénaga de Betancí, informing strategies for improving habitat conditions for the Bocachico, and supporting wetland restoration efforts.

Field surveysin rural Tanzania reveal key opportunities for targeted larval source management and species sanitation to control malaria in areas dominated by Anopheles funestus.

Larval source management (LSM) is re-emerging as a critical malaria intervention to address challenges associated with core vector control tools, such as insecticide-treated nets (ITNs), and to accelerate progress towards elimination. Presently, LSM is not widely used in rural settings and is instead more commonly applied in urban and arid settings. A systematic entomological assessment was conducted in rural communities of southeastern Tanzania, where insecticide-treated nets (ITNs) are widely used, to explore opportunities for deploying LSM to improve malaria control. Aquatic habitat surveys were conducted in 2022 and 2023 to understand habitat usage by different mosquito vectors, covering five villages during the rainy season and seven villages during the dry season. Additionally, samples of adult mosquitoes were collected to assess the role of various Anopheles species in malaria transmission in the area, and to explore opportunities for species sanitation using targeted LSM. Adult mosquito surveys showed that in this area, the total entomological inoculation rates (EIR) for indoor collections were 20.1 and 6.5 infectious bites per person per year for outdoors. Anopheles funestus and Anopheles arabiensis were the only Anopheles vectors identified. Anopheles funestus was responsible for over 97.6% of the malaria transmission indoors and 95.4% outdoors. The concurrent larval surveys found that habitats with late instar An. arabiensis and An. funestus comprised only a small subset of 11.2%-16.5% of all water bodies in the rainy season, and 9.7%-15.2% in the dry season. In terms of size, these habitats covered 66.4%-68.2% of the total habitat areas in the wet season, reducing to 33.9%-40.6% in the dry season. From the rainy season to the dry season, the surface area of habitats occupied by An. arabiensis and An. funestus decreased by 92.0% to 97.5%, while the number of habitats occupied by An. arabiensis and An. funestus decreased by 38.0% to 57.3%. Anopheles funestus preferred large, permanent habitats with clear water and vegetation year-round, while An. arabiensis showed contrasting seasonal preferences, favouring sunlit still waters in the rainy season and larger, opaque habitats in the dry season. These findings suggest that An. funestus, which is the dominant malaria vector in the area, mediating over 95% of malaria transmission, preferentially occupies only a small subset of uniquely identifiable aquatic habitats in both wet and dry seasons. This presents an opportunity to expand LSM in rural settings by carefully targeting An. funestus habitats, which might be effective and logistically feasible as a complementary approach alongside existing interventions. Further research should assess the impact of targeted LSM for species sanitation compared to blanket LSM.

Seasonal Variation of Physicochemical Properties in the Lower River Benue, Nigeria

The study investigates the impact of seasonal changes on water quality in the River Benue, Nigeria. Conducted over eighteen months from January 2020 to June 2021, the research focuses on three locations: Ibi, Lau, and Mayo-Ranewo. Key physicochemical parameters such as temperature, pH, turbidity, conductivity, Biochemical Oxygen Demand (BOD), hardness, dissolved oxygen (DO), fluoride, and nitrate were measured to assess water quality. The findings reveal significant seasonal variations in these parameters, influenced by rainfall patterns, land use, and anthropogenic activities. Temperature ranged from 25.56°C to 30.70°C, remaining within acceptable limits for tropical waters, supporting stable biological processes. However, turbidity levels exceeded recommended values, indicating the presence of suspended solids that could impair water quality and harm aquatic life. Total dissolved solids (TDS) and conductivity showed potential contamination risks, likely due to agricultural runoff and urban discharges. Dissolved oxygen (DO) levels were generally adequate, especially during the wet season, enhancing oxygen content through increased photosynthetic activity and water inflows. However, BOD spiked with rainfall, signalling organic pollution and potential eutrophication risks. Seasonal shifts in pH and water hardness reflected changes in runoff and photosynthesis, with values largely within acceptable ranges for aquatic life. Fluoride and nitrate concentrations increased in the wet season, primarily due to agricultural runoff, highlighting the influence of land-based activities on water quality.

Population size and structure of Grant’s gazelle and lesser kudu in Geralle National Park, Southeastern Ethiopia

Background Grant’s gazelle and lesser kudu remain widespread within and outside protected areas. Current pressures on their populations, human encroachment and disturbance associated habitat modifications, and excessive grazing pose further threats to the species. The estimation of density and abundance of species has significant value for sustainable wildlife management in Geralle National Park (GNP) and also contributes towards a more accurate global population estimate. Result Using distance sampling methods, the lowest Akaike Information Criterion (AIC) (close to zero) and Chi-square tests (P value > 0.05) showed that the hazard rate key function with an un-equal interval group model was selected for estimation of density and abundance. The density of species was 1.7 ± 0.5, 2.07 ± 0.7, gazelle/km2 and 1.39 ± 0.3, 1.92 ± 0.42, lesser kudu/km2 during the dry and wet seasons, respectively. Population density, abundance, and structure showed habitat and seasonal differences in observation. More individuals of both species were recorded during the wet season as compared to the dry season. Grassland was favored by Grant’s gazelle, while lesser kudu preferred woodlands. Both species exhibited a female-biased sex ratio, indicating potential for future population growth prospects. Conclusion It can be concluded that GNP is home to viable populations of Grant’s gazelle and lesser kudu, and season has influenced population abundance and distribution due to resource availability variations among seasons. The female-biased sex ratio indicates the future population growth prospects for the two species.

Evaluating the Effects of Fertilizer Deep Placement on Greenhouse Gas Emissions and Nutrient Use Efficiency in Wet Direct-Seeded Rice During the Wet Season in Assam, India

Mitigation of greenhouse gases (GHGs), improving nutrient-use efficiency (NUE), and maximizing yield in rainfed lowland rice cultivation poses significant challenges. To address this, a two-year field experiment (2020 and 2021) was conducted in Assam, India, to examine the impact of different fertilizer-management practices on grain yield, NUE, and GHGs in wet direct-seeded rice (Wet-DSR) during the kharif season. The experiment included eight treatments: control; farmer’s practice (30-18.4-36 kg N-P2O5-K2O ha−1); state recommended dose of fertilizer (RDF) @ 60-20-40 kg N-P2O5-K2O ha−1 with N applied in three splits @ 30-15-15 kg ha−1 as basal, at active tillering (AT), and panicle initiation (PI); best fertilizer management practices (BMPs): 60-20-40 kg N-P2O5-K2O ha−1 with N applied in three equal splits as basal, at AT, and PI; and fertilizer deep placement (FDP) of 120%, 100%, 80%, and 60% N combined with 100% PK of RDF. The experiment was arranged out in a randomized complete block design with three replications for each treatment. The highest grain yield (4933 kg ha−1) and straw yield (6520 kg ha−1) were achieved with the deep placement of 120% N + 100% PK of RDF. FDP with 80% N + 100% PK reduced 38% N2O emissions compared to AAU’s RDF and BMPs, where fertilizer was broadcasted. This is mainly due to the lower dose of nitrogen fertilizer and the application of fertilizer in a reduced zone of soil. When considering both productivity and environmental impact, applying 80% N with 100% PK through FDP was identified as the most effective practice.

Determinant Factors of Microbial Drinking Water Quality at the Point of Use in Rural Ethiopia: A Case Study of the South Gondar Zone

Access to safe drinking water is a fundamental human need for health and well-being implemented globally by the United Nations under Sustainable Development Goal (SDG) 6. Storing drinking water is common in rural areas of Ethiopia due to off-premises water sources and intermittent piped water supply. However, this practice can lead to further contamination during collection, transport, and storage, posing a risk to public health. The objective of this study was to identify the determinant factors of drinking water quality at the point of use in the rural setting of northwestern Ethiopia, South Gondar zone. A questionnaire survey was conducted, and water samples from 720 households were collected during the wet and dry seasons. The determinant factors were identified using the multivariable logistic regression model. About 39.2% of the surveyed households had basic water supply services, 41.9% were using unimproved sources, and 8.3% were using surface water. Only 9.4% were using basic sanitation services, and 57.2% were practicing open defecation. Safe water storage was practiced by 84.3% of households, while only 2% engaged in household water treatment. About 14% of dry and 8% of wet season samples from the storage were free from fecal coliform bacteria. Furthermore, 52.9% of dry and 62.2% of wet season samples fell under the high microbial health risk category. The season of the year, the water source type, storage washing methods, and the socioeconomic status of the household were identified as key predictors of household drinking water fecal contamination using the multivariable logistic regression model. It was observed that the drinking water in households had a high load of fecal contamination, posing health risks to consumers. To tackle these problems, our study recommends that stakeholders should enhance access to improved water sources, implement source-level water treatment, increase access to improved sanitation facilities, advocate for safe household water management practices, and endorse household water treatment methods.

Extreme Precipitation Events During the Wet Season of the South America Monsoon: A Historical Analysis over Three Major Brazilian Watersheds

Most of South America, particularly the region between the southern Amazon and southeastern Brazil, as well as a large part of the La Plata Basin, has its climate regulated by the South American Monsoon System. Extreme weather and climate events in these areas have significant socioeconomic impacts. The Madeira, São Francisco, and Paraná river basins, three major watersheds in Brazil, are especially vulnerable to wet and drought periods due to their importance as freshwater ecosystems and sources of water for consumption, energy generation, and agriculture. The scarcity of surface meteorological stations in these basins makes meteorological studies challenging, often using reanalysis and satellite data. This study aims to identify extreme weather (wet) and climate (wet and drought) events during the extended wet season (October to March) from 1980 to 2022 and evaluate the performance of two gridded datasets (CPC and ERA5) to determine which best captures the observed patterns in the Madeira, São Francisco, and Paraná river basins. Wet weather events were identified using the 95th percentile, and wet and drought periods were identified using the Standardized Precipitation Index (SPI) on a 6-month scale. In general, CPC data showed slightly superior performance compared to ERA5 in reproducing statistical measures. For extreme day precipitation, both datasets captured the time series pattern, but CPC better reproduced extreme values and trends. The results also indicate a decrease in wet periods and an increase in drought events. Both datasets performed well, showing they can be used in the absence of station data.

Impacts of climate change and deforestation on fire risk in the Amazon basin

Fires in the Amazon rainforest are a result of anthropogenic activity in the region. As the Amazon rainforest becomes vulnerable to fire through deforestation and climate change, it is imperative to understand how the fire risk will change in future years—not only for the potential of the forest to become a source of carbon to the atmosphere if burned but also for the potential loss of unique biodiversity and its critical role in regional and global climate. Therefore, we used the Eta regional climate model driven by 3 global climate models to simulate 2 distinct scenarios: one with a high CO2 emission (RCP8.5-DEF15) path and another with a high CO2 emission path and the total deforestation of the Amazon rainforest (RCP8.5-DEFTOT). Combining the multi-model ensemble of temperature and precipitation, we calculated the Keetch-Byram Drought Index (KBDI) and analyzed the results for the dry and wet seasons. In both scenarios, precipitation is reduced and maximum temperature increased. The greatest changes occur during the dry season and with the RCP8.5-DEFTOT scenario. In RCP8.5-DEF15, the KBDI is greatly affected, showing positive anomalies in both seasons. With the addition of deforestation, the fire risk is further exacerbated, thus highlighting the role of the forest in suppressing optimal conditions for fire. Additionally, more than half of the basin area is predicted to experience a high risk of fire in extreme years. Our results emphasize the importance of reducing global emissions and deforestation of the Amazon, given that fire activity could threaten the future of the Amazon rainforest.

Projections of future bioclimatic indicators using bias-corrected CMIP6 models: a case study in a tropical monsoon region.

This study evaluates the potential impacts of climate change on Bangladesh by analyzing 19 bioclimatic indicators based on temperature and precipitation. Data from 18 bias-corrected CMIP6 global climate models (GCMs) were used, covering four Shared Socioeconomic Pathways (SSPs)-SSP126, SSP245, SSP370, and SSP585-across three future timeframes: near-term (2015-2044), mid-term (2045-2074), and long-term (2075-2100). Under the high-emission SSP585 scenario, average temperatures are projected to rise by up to 3.76°C, and annual precipitation could increase by 52.6%, reaching up to 3446.38mm by the end of the century. The maximum temperature (Bio5) could reach 32.91°C, while the minimum temperature (Bio6) might rise by 4.43°C, particularly during winter. Precipitation seasonality (Bio15) is projected to increase by as much as 7.9% in the northwest, indicating heightened variability between wet and dry seasons. The diurnal temperature range (Bio2) is expected to decrease by up to - 1.3°C, signifying reduced nighttime cooling, which could exacerbate heat stress. Significant reductions in temperature seasonality (Bio4) are forecast for the northeast, with notable declines in isothermality (Bio3) under SSP585, pointing to increased climatic extremes. These climatic shifts pose severe risks to agricultural productivity, water resource availability, and biodiversity, particularly in flood-prone regions. The findings highlight the need for urgent adaptation measures, including improved flood management systems, efficient water resource use, and climate-resilient agricultural practices. By providing robust region-specific projections, this study offers critical insights for policymakers and stakeholders to mitigate the adverse effects of climate change and safeguard environmental and economic sustainability in Bangladesh.

Remote sensing and GPS tracking reveal temporal shifts in habitat use in nonbreeding Black‐tailed Godwits

Abstract Knowledge of the habitat requirements for migratory species throughout their full annual cycle is necessary for comprehensive species protection plans. By describing seasonal shifts of space‐use patterns in a key nonbreeding area, the Senegal Delta (Mauritania, Senegal), this study addresses a significant knowledge gap in the annual cycle of the rapidly declining continental Black‐tailed Godwit Limosa limosa limosa. We fitted continuous‐time stochastic‐process movement models with GPS location data to describe the core areas used by 22 GPS‐tagged godwits over the 2022–2023 nonbreeding period. We mapped key habitat types, such as floodplain wetlands and rice fields, via supervised classification of satellite imagery. Godwits in the Senegal Delta show a distinct shift in habitat use over the nonbreeding period. The core areas of godwits in the early stages of the nonbreeding period (the wet season) were primarily in natural wetlands and fields with newly planted rice. As the rice crop matured and became too dense, godwits moved towards more recently sown rice fields. Later, as floodwaters receded and rice fields dried out, godwits abandoned rice fields and shifted towards natural wetlands with fewer invasive plants, particularly within the marshes and shallow floodplains of nature‐protected areas in the lower Delta. Synthesis and applications: Our findings illustrate the shifting importance of natural and agricultural wetlands for godwits at different stages of the nonbreeding season. Protected areas in the Senegal Delta, particularly the Djoudj National Bird Sanctuary (Senegal) and Diawling National Park (Mauritania), are crucial habitats during the dry season as godwits prepare for their northward migration, whilst rice fields take a key role during the wet season. Conservation efforts should prioritize eradicating invasive plants from the Djoudj and Diawling, as well as promote agroecological management in specific rice production complexes indicated in this study.

Human–African buffalo conflict: perceptions of damage, and mitigation strategies, in villages bordering Ngorongoro Conservation Area, Tanzania

Abstract Human–wildlife conflict is a critical and complex challenge in wildlife conservation. It arises when humans and wildlife interact and one or both parties suffer negative consequences from the interaction. This research assessed the extent of damage resulting from human–African buffalo Syncerus caffer conflict and explored mitigation strategies. We used a semi-structured questionnaire-based survey of 131 households randomly selected in Kambi ya Simba, Oldeani and Tloma villages surrounding Ngorongoro Conservation Area, Tanzania. Our results revealed that resource competition was the main factor inducing human–African buffalo conflict. The impacts reported most frequently were crop damage (especially during the wet seasons) and human casualties. Crops that were most often damaged included maize, beans, wheat, peas and coffee. To minimize buffalo crop depredation, farmers currently use traditional mitigation approaches such as guarding farms, lighting fires, using torchlight and vocal and other auditory deterrents. In addition, a local coffee estate installed electrified fencing around its plantation. Our findings demonstrate the impacts of human–African buffalo conflict on local communities and the importance of continuing human–African buffalo conflict monitoring to improve conservation action and increase the participation of the local community in conservation activities. To minimize human–African buffalo conflict, we recommend conservation strategies that improve the natural habitat of the African buffalo. Most importantly, providing communities affected by human–African buffalo conflict with modern and more effective mitigation methods, paired with increased community awareness of the use of these methods, could result in significant reductions in the human cost of human–African buffalo conflict.

Pertubations of Physicochemical Properties and Heavy Metal in the Soil of Coastal Areas of Akwa Ibom State, Nigeria

This study aimed at assessing the concentrations and perturbations of the physicochemical properties and heavy metals in the soil of the coastal regions of Akwa Ibom State, Nigeria. Sampling was carried out across three mangrove locations (Iko Town, Okoroutip and Uta Ewa) in Eastern Obolo, Ibeno and Ikot Abasi Local Government Areas respectively. Four vegetation plots were randomly selected, and within each plot, three belt transects were established. Physicochemical properties [Sand, Clay, Silt, organic carbon (OC), total nitrogen, sulphate and chlorine content] and heavy metals (Arsenic, Silver, Chromium, Copper, Nickel, Lead, Mercury, Cadmium, Titanium, Vanadium and Zinc) were analyzed using standardized methods. Results from this study revealed considerable variations in the physicochemical properties of soil in the study area. The aforementioned heavy metals were present in both wet and dry seasons in considerable concentrations in the soil samples within the study areas. However, were within and below WHO limits. The variations in the physicochemical properties and the presence of these heavy metals in the samples are indicative of an impacted environment unsuitable for the growth and survival of the endemic flora and fauna species of this unique ecosystem. In view of the current knowledge of the role of mangrove ecosystems in blue-economy of the nation and mitigation of ongoing climate change, we advocate a tripartite alliance between the government, multinational companies operating within the area and the various impacted communities that leads to a concerted efforts of constant monitoring and remediation in the reduction of current and future pollutant levels.

Factors influencing the variability in performance of cattle grazing tropical pasture

Context Whereas it is known that there is variation in liveweight gain (described as performance in this paper) within a group of grazing cattle, the causes of this variation are not well understood. Aim A 2-year grazing study in northern Queensland was conducted to understand the relative influence of diet selection, grazing behaviour and rumen fermentation on variation in performance of growing cattle. Methods Eighty-nine Bos taurus × B. indicus (~6 months old) growing steers were grazed as a group on mixed tropical pasture for 23 months. Pasture was characterised for biomass, species and nutrient composition. Cattle were ranked according to overall liveweight (LW) gain and the top (high performance, HP) 20 and bottom (low performance, LP) 20 head were compared for diet composition, rumen fermentation and grazing behaviours. Results Pasture biomass, and nutritive value of pasture and diet varied between seasons and years of study. The HP cattle achieved overall LW gains 20% greater than those of the LP cattle mainly due to higher rates of gain in the wet season. However, the nutritive value and rumen fermentation characteristics were similar for both LP and HP cattle, although there was evidence that crude protein and digestibility were modestly higher in diets of HP cattle, especially in the first wet season. Activity, measured as distance travelled, declined as pasture biomass declined, and cattle appeared to favour pasture with higher legume content. Conclusion It is concluded that divergence in performance of cattle on tropical pasture could not be fully explained by measurements taken in this study. Diet selection for plant components with improved nutritive value probably played a small role. Differences in initial LW between the LP and HP groups may have been a contributory factor. Implications Despite comprehensive measurements of factors that influence efficiency and performance on pasture, we were unable to identify definitive causes. Genetic variation in feed intake or efficiency of digestion needs to be investigated.

Contrasting patterns of Asaia association with Plasmodium falciparum between field-collected Anopheles gambiae and Anopheles coluzzii from Cameroon.

The widespread prevalence of Asaia in mosquitoes makes it a potential candidate for paratrangenic control in Anopheles. To better understand whether this bacterium could be used for malaria control, we quantified Asaia in An. gambiae s.l populations in malaria endemic regions examining co-infection with Plasmodium falciparum. Adult Anopheles mosquitoes were collected across two different eco-geographical localities in Cameroon, during both the dry and wet seasons. DNA was extracted from whole individual mosquitoes, and real time-qPCR amplification of the 16S ribosomal RNA was used to quantify Asaia in both An. gambiae and An. coluzzii samples. We also detected and quantified P. falciparum infection in the same mosquitoes. The density of Asaia was successfully quantified in a total of 864 field mosquitoes, comprising of 439 An. gambiae from Bankeng and 424 An. coluzii collected from Gounougou. Interestingly, a higher prevalence of Asaia in An. gambiae (88.3%) compared to An. coluzzii (80.9%) was observed. Moreover, the density of Asaia in both species was significantly affected by seasonal changes in the two localities. Furthermore, a significant difference between the infection densities of Asaia and the Plasmodium infection status in the two species was recorded. However, no correlation was observed between the number of Asaia and P. falciparum infections. This study provides evidence that naturally occurring Asaia infection is not correlated to P. falciparum development within An. gambiae and An. coluzzii. Nevertheless, further studies incorporating experimental infections are required to better investigate the correlation between Anopheles mosquitoes, Asaia, and Plasmodium.IMPORTANCEThe symbiont Asaia has emerged as a promising candidate for paratransgenic control of malaria, but further analysis of its biology and genetics across Africa is necessary. In this study, we investigated and quantified the influence of Asaia in naturally infected An. gambiae s.l. populations with the malaria parasite Plasmodium falciparum. Genomic DNA was extracted from whole individual mosquitoes collected from two localities, and Asaia was quantified using real-time qPCR by amplification of the 16S ribosomal RNA gene. We also detected and quantified Plasmodium falciparum infection in the same mosquitoes and established the correlation between Asaia and Plasmodium coinfection. This study provides evidence that naturally occurring Asaia infection is not correlated with P. falciparum development within An. gambiae and An. coluzzii mosquitoes.

Contributions of Stationary and Transient Water Vapor Transports to the Extreme Precipitation Changes Over the Tibetan Plateau

AbstractThe Tibetan Plateau (TP) has experienced “south drying‐north wetting” extreme precipitation changes over the past half century. The effects of water vapor transport at different timescales on TP extreme precipitation changes remain unexplored. Here, we utilize the reanalysis data sets to quantify the contributions of stationary and transient processes of water vapor transport to the long‐term changes in the extreme precipitation (R95p) during wet season (Jun‐Jul‐Aug‐Sep) over the TP and surrounding regions. We find that the daily scale transient processes dominate the dipole trend of extreme precipitation with a contribution of 55.1% in the northern and 79.5% in the southern TP, respectively, whereas the contribution of monthly scale stationary processes is of 19.0% and 20.5%. The long‐term changes in extreme precipitation are dominated by the transient dynamic component. We identified the synoptic circulation patterns affecting the changes of R95p over the northern and southern TP by using k‐means clustering. The patterns featured with a 500 hPa trough, 200 hPa wind divergence and low transient geopotential height are identified. The frequency of the dominant circulation patterns increases in the northern TP and decreases in the southern TP, which leads to the dipolar changes of extreme precipitation over the TP and surrounding regions.

Impact of Seasonal Changes on Avifauna Diversity in Nguru Wetland, Yobe State, Nigeria

The research on impact of seasonal changes on avifauna diversity in Nguru Lake of Hadejia-Nguru Wetland was carried out in two different seasons for the period of six 6 months, from April to June (dry season) and July to September (wet season). The aim was to evaluate the impact of seasonal changes on avifauna diversity and the species richness in the study area. A reconnaissance survey was carried out to select study sites and sampling points. Five (5) different points were selected which comprises of Madauka, Kayayyashi, Farin Ruwa, Badum and Guzan respectively and Point count census techniques were adopted. In each counting station, bird observation was carried out twice daily; morning between 6:00 am and 10:00 am and evening between 4:00 pm and 6:00 pm. Data compilation was done using Microsoft Excel and were analysed using statistical software Past 326b. Bird diversity was calculated using Shanon-Weiner diversity index. The findings of this research showed that the majority of birds identified were Resident species (12,225 individual birds), Migratory species (8,186 individual birds) and Palearctic Migrants (10,876 individual) species in the study area. Dominant bird species in Nguru lake were Philomachus pugnax, Actophilornis africanus and Phalacrocorax africanus. A total of 5,538 individual birds’ was identified (Dry Season) in Nguru lake ‘’ belonging to 21 families in which Ardeidae family had the highest (7) species of bird. Shannon Diversity Index’ has 2.55 in dry season, while in Wet Season’ has 3.40. This indicated that there was relatively equal and high diversity of bird species in Wet Season in the study area and has the total species richness of 6,711. Overgrazing and other anthropogenic activities which affect the population diversity of avifauna species serve as major threats to the continued existence of Wetlands. Typha grass also remained pressing problem which create microhabitats reducing critical habitat for feeding, nesting and roosting habitat for birds, as well as hampers the smooth flow of water used by many water bird species. In view of the findings of this study, effective monitoring and strategies for conservation to restore the population of bird species, provide public enlightenment of the people around the wetland and management of Hadejia-Nguru Wetland promptly advice the significant importance of the wetland in serving as home for resident and migratory birdspecies.

Collaborative Research for the Development of Localized Solar PV Output Forecasting Models for the Philippines Using Geospatial Data

Abstract. This paper presents a collaborative effort to develop localized solar photovoltaic (PV) power output (PPV) forecasting models for the Philippines using geospatial data. It underlines the importance of solar energy in the country and discusses the opportunities and challenges associated with PPV forecasting. Project SINAG, a two-year research project, aimed to develop solar PV output forecasting models through a collaborative approach with academic institutions, solar energy industries, and government agencies. Actual PPV data from 43 solar PV installations were analyzed alongside meteorological data from the PAGASA weather bureau, ERA5, AHI-8, and FY- 4A. These datasets were filtered based on a one-year period to ensure quality. The study employed SARIMAX, LSTM, and XGBoost models individually and in hybrid models to develop the forecasting models. Model performance was evaluated using root mean square error (RMSE), mean absolute error (MAE), and mean absolute percentage error (MAPE). In a case study in Baguio City, the SARIMAX model exhibited strong seasonal dependence, providing more accurate forecasts in dry seasons than in wet seasons. Additionally, the forecasting accuracy of each model (SARIMAX, LSTM, and XGBoost) varied based on the month and location of the installation, emphasizing the need for local and season-based PPV forecasting models. Despite implementation challenges, such as collaboration arrangements, bureaucratic barriers, and budget constraints, the project produced thirteen research publications and provided data for three student theses. This paper also demonstrated diverse engagements and contributions that emphasize the significance of collaborative research in conducting nationwide-scale data-driven projects.

Coexistence mechanisms and individual trophic niche variation between functionally analogous non-native and native carp species

Understanding the mechanisms that promote coexistence between functionally analogous non-native and native species that share similar prey is important for predicting the ecological consequences of their competitive interactions. Theory predicts that species coexistence is facilitated by stabilizing mechanisms that enhance inter-specific trophic niche partitioning, and/ or the equalizing mechanisms that reduce differences in the average fitness. Inter-specific niche partitioning, influenced by the ecological opportunity in prey resources, also affects intra-specific niche partitioning and individual niche expansion. These theories were tested using the non-native mrigal carp Cirrhinus mrigala and its congener native mud carp C. molitorella that coexist across the Pearl River basin, Southern China, with their trophic interactions analysed using DNA metabarcoding on fish gut contents sampled across the basin in both the dry and wet seasons of 2019 and 2021. The results revealed that the inter-specific trophic niche overlap was lower than their intra-specific trophic niche overlap, suggesting their coexistence was supported by stabilizing mechanisms. The ecological opportunity in prey resources was driving inter-specific niche partitioning and this partitioning then positively influenced intra-specific niche partitioning and individual niche expansion, especially in mrigal carp that had larger body sizes and occupied higher trophic positions at constricted individual niches. Fish body size also affected inter-specific niche partitioning and the relationship between inter- and intra-specific niche partitioning, with positive effects on both in mrigal carp but negative effects on both in mud carp. The results thus provide a mechanistic explanation on how closely related non-native and native species coexist and highlight the importance of dietary plasticity in facilitating the invasion of non-native species.

Spatiotemporal distributions, sources, and health risks of heavy metals in an acid mine drainage (AMD)-contaminated karst river in southwest China

Acid mine drainage (AMD), characterized by its acidity and high content of heavy metals, is a significant global environmental problem that harms human health through its impact on rivers. Therefore, this study aims to identify heavy metals in both surface and underground AMD-polluted karst rivers, focusing on the Zhijin River area which is severely affected by AMD, and assess their health risks to residents. Through the collection of 30 surface water samples and 16 groundwater samples from both wet and dry seasons, the study examines the concentration, sources of pollution, and health implications of six heavy metals (Fe, Mn, Cr, Cd, As, and Hg). The results showed that Fe and Mn levels in surface water were highly polluted during both seasons, especially during the wet season, with Fe levels reaching 20.0 mg/L and Mn levels reaching 1.9 mg/L. Further correlation and principal component analyses revealed that mining activities are the primary contributors to the contamination in this region. Health risk assessments and Monte Carlo simulation, including both deterministic and probabilistic, showed that the noncarcinogenic health risk indices for surface water and groundwater were within acceptable limits for both seasons. However, groundwater poses a higher carcinogenic risk to children, with As levels during the wet season and Cr levels during the dry season warranting close monitoring. Factors such as body weight and intake rate played a crucial role in health risk evaluations. This study underscores the need for further attention to groundwater risk, temporal heterogeneity in the Zhijin River.