To evaluate the effects of seasonal fluctuations, soil types, land use and management inputs on the abundance and composition of soil bacteria, twenty soils types from Moldavia region located in north-eastern Romania were compared. Changes in soil microbiota are an early and sensitive indicator of soil pollution and can be used to predict long-term trends in soil quality. The use of microbial properties as indicator of soil pollution is easily measured and can also be measured accurately across a wide range of soil types and conditions. The dynamics of the bacterial community from all soil types were ranked as follows: spring 2012 (164.8 x 106 CFU g–1) > spring 2013 (147.7 x 106 CFU g–1) > autumn 2012 (80.6 x 106 CFU g–1) > autumn 2013 (79.4 x 106 CFU g–1). In case of land use and soil management practices (conventional, organic, and unmanaged) the bacterial abundance increased in the following order: vineyards < permanent grassland < arable land under crop rotation < hardwood forest < vegetable crop < hay crop. Our results suggest that seasonal variation, land use and soil management have a significant impact on bacterial richness and diversity (p < 0.05 in all cases). Extensive use of xenobiotic compounds in agriculture degrades soil microbial communities as they affect microbial abundance and composition, directly, and soil texture and fertility, indirectly.