ABSTRACT

This study dealt with analysis of physicochemical parameters, heavy metals in bottom and plankton characteristics of earthen ponds in Michael Okpara University of Agriculture, Umudike Nigeria. The ponds were constructed on low land and therefore prone to runoffs loaded with degradable and non-degradable materials deposited at different degrees in different sections of the farm. For the purpose of this study, the farm was divided into three sections in relation to flooding as; flood free area, low flood area and high flood area. The analysis was carried out to provide empirical data that could be informative in management of earthen ponds in flood prone environment for production of fish for human consumption. Lead, zinc, iron, cadmium were analyzed using atomic absorption spectrophotometer (AAS), dissolved oxygen (Do), Biological oxygen demand(BOD), total dissolved solids(TDS), electrical conductivity (Ec), nitrate, phosphate, temperature, pH, and transparency were analysed using DO meter, TDS meter, conductivity meter, pH meter, thermometer and secchi disc respectively. Plankton was analyzed by filtering water samples through a fine plankton net of mesh size 55um and viewed under microscope for identification. Results obtained showed that DO, BOD, EC, phosphate, temperature, pH were significantly different at 5% probability level (p<0.05) among the different sections of the farm with the following mean values DO had the highest value in sections as 4.78. section 2 4.63 and sectionl 4.19. BOD was highest in Sectionl as 2.08, section2 2.05 and sections 1.78. EC was highest in sectionl as 156.08, sections 114.58 and Section2 83.42. phosphate was highest in sectionl as 1.44, Sections 0.95 and section2 0.13. However, TDS, N03 and transparency were not significantly different among ponds in different sections of the farm. TDS had the highest mean value 73.08 in section3, 70.19 in section2 and 63.41 in sectionl. Nitrate was highest in section3 as 22.04, section2 21.33 and sectionl 19.37. Heavy metals results showed that Pb, Zn, cd, Fe were significantly different at 5% probability level among the various ponds. Results on plankton abundance showed that some ponds were more productive than others which agree that impartation of runoff is at different degree. Sectionl ponds recorded the highest number of plankton which could be linked to the low values of cd, nitrate, TDS. EC values were also high in same section which means that nutrients are better circulated in it. It was recommended that physicochemical parameters should be monitored regularly to make sure they are within the recommended range.