Dehydrogenase and Phosphatase Activities in Soils under Arid Ecosystems as Influenced by Tillage, Soil Depth and Crop Rotation

摘要

A field study was conducted to determine the activity of acid phosphatase, alkaline phosphatase and dehydrogenase in soils after three years of crop rotation (pearl millet-pearl millet-pearl millet, clusterbean-pearl millet-clusterbean, mung bean-pearl millet-mung bean, moth bean-pearl millet-moth bean), and tillage operations (conventional tillage, no-tillage) at four different soil depths (0-2.5, 2.5-5, 5-15, 15-30 cm). The activity of soil phosphatases increased significantly after three years inall four crop rotations evaluated, with maximum activity being under the moth bean-pearl millet-moth bean rotation. The build up of alkaline phosphatase and dehydrogenase was higher under unfilled plots. Depth-distribution studies showed that all the three enzyme activities were concentrated in surface soils and decreased with depth. In general, the enzyme activity was more when pearl millet was planted in rotation with legumes and crops grown under tilled condition.