COMPARATIVE STUDY ON BIOLOGICAL ACTIVITY AND EDAPHIC MICROFLORA COMPOSITION FOR FOUR SOIL TYPES FROM SDE TIMISOARA PUBLISHEDRenata Maria Şumălan, Ersilia Alexa, Monica Negrea, Ancuţa Doncean
Biological diversity is affected by soil conditions and intensive agriculture technologies and reduces the chances of soil to be regarded as sustainable and renewable resource. Biological component of soil is first affected by the cultivation method or technology adopted. Thus, in recent year’s research in the world are focused on the quantification of the beneficial partnerships established between microbial diversity, soil and product quality, off course maintaining ecosystem sustainability. Activity of edaphic microflora and response to various stress factors can be estimated by different methods: determination of total number of micro organisms, established of respiration rates or estimation of the microbial biomass. In our work paper we proposed a comparative study of biological activity for four soil types’ Chernozem, vertisol, phaeozem and gleysol typical, soils found in the Didactic Experimental Station of Timisoara. Soil samples were collected in October 2009 by the depth of 10-20 cm, and were analyzed the physical-chemical and pedological property. The method used for determining the total biological activity was proposed and optimized to soil study by Green, Stott and Diack in 2005. It is based on the hydrolysis capacity of fluorescein diacetate (FDA) by most representatives’ species of soil microflora resulting fluorescein is then determined spectrophotometrically. In the same times were performed on average of total cultivable heterotrophic microorganisms of soil on the special media in order to estimate the quantitative and qualitative microbial load specific to each type of soil in part. We determined total heterotrophic soil bacteria on the Topping media, the number of actinomycetes on Berezova media and total soil fungi using Martin media. Remarkable results achieved showed differences between the soils studied the ability of fluorescein diacetate hydrolysis of being positive correlation with carbon content of soil and moisture. Quantity and composition of edaphic microflora is different, the proportion between different groups of soil microorganisms linking depending on your soil pH.
FDA hydrolysis; soil biological activity; edaphic microflora