IMPACT OF NATURAL CAPITAL INVESTMENT STRATEGIES ON WATER QUALITY IN THE NDEMBERA RIVER SUB-CATCHMENT, TANZANIA
Free (open access)
133 - 144
NORBERT J. NGOWI, ADELAIDE E. SALLEMA
Natural capital investment strategies are a highly important tool in the sustainability of ecosystem services – including water and improved community livelihoods worldwide. However, their implications on the quality of water are hardly known in many societies of Tanzania. This paper reports the effect of one of such strategy, called Wetland Friendly Investment (WFI), on the quality of water on small parts of Ndembera sub-catchment of Tanzania, where (WFI) has been implemented for more than a decade. Samples of water were collected from the seven locations in the dry and wet seasons using 1,500 ml plastic tubes. Bottles with samples were labeled, stored in the cooling box and transported to the laboratory for analysis. All parameters were measured using standardized methods. To determine the effect of the strategy, we compared the measured mean difference values of the physicochemical properties of water before and after the introduction of the strategy using a two-way Analysis of Variance (ANOVA). The results showed that there was a statistically significant difference in Total Suspended Solids (TSS) before (p = 0.0066) and after (p = 0.0324) the intervention. Msugulika stream and the upstream of Ndembera River had the highest value for Ammonia-Nitrogen, with means of 0.3 and 0.23 mg/l in the dry and wet seasons, respectively. The use of agrochemicals was mentioned as one of the contributing factors in the poor quality of water and this could not significantly be reduced by the introduction of the WFI strategy alone. Therefore, more robust actions are required in addressing the issue of the quality of water in the sub-catchment.
Ndembera River sub-catchment, physicochemical, wetlands friendly investment, natural capital.