Macro-vegetation and physicochemical aspects of Tirwum pond in Bauchi Local Government Area of Bauchi State, Nigeria

Abstract

Water is a key player in any biological system and it is vital to quality existence of living things. The abundance, assemblage, density, diversity and kinds of macro-vegetation present in a system are pointers to ecological health and the knowledge of biodiversity upsurge or decline is necessary for management decisions at various levels. In the evaluation of Macro-vegetation and some physicochemical factors of Tirwum pond, samples were collected once a month for six consecutive months. According to the manufacturer’s operating procedure as approved by EPA, Colorimeter hach DR 890 was used to determine turbidity, HANNA HI 9813-5 was used to determine total dissolved solids (TDS), (pH) and electrical conductivity (EC), dissolved oxygen (DO) was measured by JPB-70A pen type intelligent dissolved oxygen analyzer, nitrate and phosphate were determined by means of PALINTEST photometer Wagtech 7100. The determination of TSS and TS were by filtration and evaporation methods respectively and temperature was measured in situ using mercury in glass thermometer. 60 quadrats of 1x1m2 were thrown and a long, double-headed rake dipped down, turned 360degrees within each quadrant and all plants within the quadrant frame were counted and identified. The species richness was six belonging to four families. Diversity and evenness index were 1.69 and 0.94 correspondingly. Most values of pH were within the optimum range. The above 3mg/L of all nitrogen values branded the pond as polluted. The abundance of three macro-vegetation families negatively correlated with dissolved oxygen (p˂ 0.01, p˂0.05), but positively correlated with Temperature (p˂0.05). The abundance of macro-vegetation showed negative correlation with EC and TDS (P ˂ 0.05). The absence of submerged macrophytes, high concentration of nitrate and low concentration of dissolved oxygen reflected the impaired state of the pond community and the species richness of six is bad for biodiversity at local and global level.