Soil Microbial Activity Alteration with Respect to Combined Application of Olive Mill Wastewater, Heat Treated Vermicompost and Cattle Manure

Olive mill wastewater (omww) is threatening soil microbial community due to its long-chain fatty acids and phenolic compound ingredients. the purpose of this study was to determine the effects of omww in presence of heat-treated (70 °c, 1 hour) and untreated vermicompost (vm) or cattle manure (cm) on some microbial activities in the soil. the pot experiment was carried out, where the treatments were 1% vm or 1% cm along with 500 liter ha^-1 omww. co_2 production, dehydrogenase enzyme activity (dha) and microbial biomass carbon (mbc) contents were determined as a soil microbial activity indicator of soil on the days of 1st, 15th and 30th of the experiment. results revealed that omww stimulated soil microbial activity which the higher values are determined in co_2 production, dha activity and mbc amount on omww applied pots. co_2 values in heat treated vm applied soils were found to be lower than untreated vm; however, these finding is not supported by dha and mbc results. determined mean co_2 values were 300 and 363 μg co_2 °c g soil day^-1 in heat treated vm and untreated vm variants, respectively. according to mean co_2 formation results that obtained from cm, heat treatment is stimulated co_2 production contrarily the results obtained from vm. mean co_2 values for heat treated and untreated cm were 356 and 310 μg co_2-c g^-1 soil day^-1, respectively. the mean dha values for heat treated and untreated vm and heat treated and untreated cm were 5.00, 4.28, 4.44 and 4.22 tpf g^-1 dry soil day^-1. the mbc results for same treatments were 265, 206, 266 and 367 μg mbc g^-1 soil. according to general results of this research the highest values were determined for co_2, dha and mbc on the 1st, 30th and 15th days, respectively.