Physicochemical and oligotrophic status impact on Warwade dam water quality, Dutse, Jigawa State, Nigeria

Abstract

Warwade Dam, one of the biggest dams in Dutse land, is 1.4 km long, 6 m wide, 10 m deep, and has a total capacity of 300 million cubic meters of water. It is situated between latitude 110.45'N and longitude 90.13'E. The impact of oligotrophic and physicochemical status on the water quality of Warwade Dam was examined in this study. Water samples were gathered between March 2020 and February 2022 in order to perform standard methods for physicochemical analysis and plankton organism determination. Measurements of the water's temperature, conductivity, dissolved oxygen content, and total dissolved solids were made on-site using appropriate standard equipment. Based primarily on their use as sources of agricultural irrigation and drinking water for the Warwade people, the sample locations were selected. According to the Nigeria Standard for Water Quality and the World Health Organization, Warwade Dam's water temperature, conductivity, salinity, nitrate, and phosphate levels were all within permissible bounds.The dam is classified as oligotrophic due to its low nutrient levels, as indicated by the Trophic State Index (TSI) values of phosphate 3.0 mg/l and nitrate
14.82 mg/l. The dam is also regarded as oligotrophic according to the Plankton Index (PI). The presence of genera including Daphnia,
Leptothrixocharacea, Brachionidaecaudatus, and Cyclotellamenaghimian, which are markers of oligotrophic dam in various seasons and locations, leads this study to classify Warwade Dam as an oligotrophic dam. The present investigation demonstrated statistically significant (at P value ≤ 0.05) variations in the species composition of plankton between research years and places within Warwade Dam, along with an irregular distribution of plankton abundances. Over the course of the two years of the study, all the parameters that were considered showed notable spatiotemporal (time and location) variability. Anthropogenic such as natural soluble salts, nonpoint source nutrients, and agricultural runoff and biogeochemical cycle were the main causes of the fluctuation in dam water quality. The study indicates that the dam water used for agriculture and irrigation in these adjacent Warwade districts can be considered clean, which makes it particularly suitable for usage in residential and agricultural settings as well as aquatic ecosystems. Based on the values of the obtained physicochemical parameters and oligotrophic state, It is determined that there was no significant contamination concern in the current investigation and that the water quality of Warwade Dam was good. was not prone to producing algal blooms at the time of our investigation. To preserve the current dam water quality, it is recommended that the use of excessive fertilizers and agrochemicals in agricultural processes be limited, and that the Warwade community maintain sustainable hygienic sanitation.