Impacts of Emerging Agricultural Practices on Groundwater Quality in Kahe Catchment, Tanzania

Abstract

This paper assesses the impacts of farmers’ intensive use of agrochemicals (fertilizers and pesticides) on groundwater quality in the Kahe catchment. Samples were collected during the wet and dry seasons of the year 2018 and analyzed for the presence of agrochemicals in the water. Groundwater chemistry was dominated by magnesium-sodium-bicarbonate (Mg-Na-HCO3−). The cations levels were in the trend of Mg2+ >Na+ > Ca2+ > K+, whereas anions were HCO3− > Cl− > SO42− for both seasons. The NO3− had an average value of about 18.40 ± 4.04 and 7.6 ± 1.7 mg/L in the wet and dry season, respectively. Elevated levels of nitrate, sulfate, phosphate, and ammonium were found in water samples collected near the large-scale sugarcane plantation in the catchment. For both seasons, Pb, Cd, Fe, Mn, Zn and Cu concentrations averaged approximately 0.08 ± 0.03, 0.11 ± 0.03, 0.16 ± 0.02, 0.11 ± 0.01, 0.46 ± 0.05, and 0.55 ± 0.02 mg/L, respectively. On the other hand, the concentrations were higher in shallow wells than in the deep boreholes. Pesticides’ residues were below the detection limit in all sampled groundwater. The findings from this study provide important information for intervention in groundwater quality management in Kahe Catchment, Tanzania.

Groundwater Resources Management: Reconciling Demand, High Quality Resources and Sustainability

“…Lwimbo et al's [10] case study emphasizes the impacts of farmers' intensive use of agrochemicals (fertilizers and pesticides) on groundwater quality in the Kahe catchment, Tanzania. For this study, water samples were collected during the wet and dry seasons and analysed for the presence of agrochemicals in the water.…”

“…The first theme concerns modelling efforts supporting the sustainable management of aquifer systems [8,9]. The second theme is focused on groundwater vulnerability assessments against external pollution, focusing on groundwater quality management [10][11][12][13]. The third theme explores the potentiality of geophysics tools supporting groundwater management in the case of coastal aquifers [14][15][16].…”

Effects of Restoration Techniques on Plant Diversity and Forage Biomass in Areas Invaded by Prosopis juliflora

“…Annual precipitation ranges between 275 mm and 500 mm, with most rain occurring between March and May [17]. The annual air temperature ranges from 15−36 °C, with June − August being the coldest months (15−23 °C) and January−February being the hottest months (32−35 °C) [18]. Within Kahe Ward, the study concentrated in Oria village which is highly invaded by Prosopis juliflora.…”

Hydrochemical Characteristic of Groundwater and Its Impact on Crop Yields in the Baojixia Irrigation Area, China

“…It is very difficult to study. Therefore, research on irrigation water quality is nevertheless of great significance for long-term management planning of crop yield [9,[14][15][16][17].…”

“…Too many salt ions in plants, such as Na + , inhibits the absorption of other necessary ions and affects the normal production and development of plants [6,19,21,22]. The salinity and sodium absorption ratio (SAR) of irrigation water is used to assess the impact of soil on crop yield [8,15,17,23]. Therefore, the evaluation of irrigation water quality is of great significance for the study of plant growth.…”