ABSTRACT
The water supply in drylands mainly relies on groundwater, making it a crucial resource. Springs in southern Africa are often underutilized, and are neither protected nor monitored. Thus, the aim of this study was to evaluate their quality in a sample area in northwestern Namibia and to propose solutions for the sustainable use of springs. In total, 35 springs and hot springs were evaluated in the study area located in the drier part of Namibia (Pmean = 150–400 mm/year), an area highly impacted by ongoing climate change with longer and more frequent drought seasons. The springs there are mostly uncaptured and the discharge is in the form of surface runoff, which is mainly lost to the atmosphere by evaporation. Most of the studied springs were perennial, despite a severe drought period. Local communities rely on the springs mainly for livestock and human consumption, as well as for irrigation. However, 71% of the springs do not have any protective measures. The temperature, pH, conductivity and alkalinity were tested in situ. In total, 20 samples were collected and analyzed for major ions (boron, fluoride, silica and strontium) and total dissolved solids (TDS). The physical and inorganic results mostly indicated good and excellent quality water for human consumption, while the hot springs tended to have poor water quality in terms of Namibian standards, indicating that the water was not fit for human consumption.
ABSTRACT
The COVID-19 pandemic has become a planetary concern that affecting the sustenance of the human population all around the globe. The effective measured has been taken in Malaysia to control the virus transmission by limiting the human vitality which unsurprisingly propitious to the environment. A monitoring study was conducted to assess the water quality status of surface seawater along the Port Dickson coast based on the Malaysian Marine Water Quality Index (MMWQI) and Malaysian Marine Water Quality Standards (MMWQCS) with an interval period of a year (March 2020-March 2021). In situ, water quality parameters incorporate temperature, pH, salinity, conductivity, dissolved oxygen (DO), and total dissolved solids (TDS) were measured at 14 sampling sites to evaluate the biochemical characteristics of water. Surface water samples were collected from the same sites and transported back to Universiti Putra Malaysia for nitrate (NO3-), ammonia (NH3), phosphate (PO4), biochemical oxygen demands (BOD), fecal coliform (Escherichia coli), and total suspended solids (TSS) analyses. The MMWQI showed the status of surface water from the Port Dickson coast was classified as moderate quality (50.41 - 64.05) for both sampling events. However, there are some indexes that showed significant decreases (p< 0.05) in the latter year. The concentration of nutrient pollution such as phosphate, nitrates, ammonia, fecal coliform as well as oil and grease, was decreased by 11.12%, 77.39%, 82.4%, 90.26%, and 99.9% respectively. The water parameters namely TDS, pH, and BOD levels were significantly decreased by 1.77%, 20.73%, and 77.16%. Certain parameters listed in the MMWQS such as temperature, pH, ammonia, fecal coliform, oil and grease were classified as Class 1 in March 2021. These occurrences recorded were greatly influenced by the reduction of the substantial human activities around the recreational beach of Port Dickson followed by the declaration of Movement Control Order (MCO) in Malaysia.