ASSESSMENT OF MICROBIAL AND SOIL ENZYME ACTIVITIES AS POTENTIAL INDICATORS OF SOIL QUALITYIN ULTISOLS, UYO, NIGERIA
*Godwin U. Akpan1 & Muhammed Iliyasu2
1Department of Soil Science and Land Resources Management, University of Uyo Uyo
2Department of Soil Science, University of Calabar, Calabar
Email: agumoren1@yahoo.com*Corresponding author
ABSTRACT
This study was conducted to investigate microbial biomass and soil enzyme activities as potential indicators of soil quality inultisols, Uyo, Nigeria. Soil samples for experiments were collected from old stadium Road (OSR), Old Ring Road (ORR) and Ukana Offot (UKO) at the depth of 0-20cm. soil samples for microbial and enzymatic analyses were stored in a cooler of iced block, while the samples for the determination of soil physical and chemical properties were stored in polythene bags and conveyed to the laboratory for analysis. The enzymes determined were; phosphatase, dehydrogenase, cellulase, catatase urease and invertase. The models for biological and enzyme indicator were used to determine soil quality. All the data obtained were subjected to descriptive statistics. The results showed that total heterotrophic bacteria (THB) in the study sites were 5.45 (+1.5)x106cfu/g, 3.30 (+1.0)x106cfu/g and 1.30 (0.2)x106cfu/g soil for OSR, ORR and UKO respectively. Total heterotrophic fungi were: 3.05 (+0.5) x105cfu/g, 2.00 (+0.02)x106cfu/g and 3.00 (+0.2) x105cfu/g soil for OSR, ORR and OKU respectively. The enzymological analyses showed that all the enzymes determined were present in all the samples, differences were obvious in the intensity. Potential dehydrogenase activity the only indicator of the possible sources of pollution implicated the presence of either chemical or biological pollution. Based on theoretical values of bacteria indicator (BISQ) and enzymatic activity, enzymatic indicator of soil quality (EISQ) showed low values. The low values of both BISQ and EISQ showed high anthropogenic influence and possible pollution. Key Words: Enzyme Activities, Microbial, Potential Indicators, Soil Quality, Ultisols
