Influence of ten herbicides on activities of microorganisms and enzymes in soil

The effect of ten herbicides on soil microbial and enzyme activities was researched. The chemicals were applied to a loamy sand at 10 mu g active ingredient/g of soil. An inhibitory effect on nitrification was observed with treatments of autoclaving and a nitrification inhibitor. The herbicides did not affect on mineralization and oxidation of soil-native organic sulfur. The influence of herbicides on microbial activity displayed no pattern dependent on time of incubation. All treated samples consumed greater amounts of oxygen than did controls. At the levels tested, the ten herbicides did not markedly reduce microbial and enzyme activities in soil and did not degrade soil fertility.