Soil dehydrogenase activity in agro-ecological sub regions of black soil regions in India

A survey was undertaken in the established benchmark (BM) soil series in different agro-ecological sub regions (AESR) of Black Soil Regions (BSR) in India with an objective to study the impacts of bio-climates, cropping systems and land use systems on the distribution of dehydrogenase activity (DHA) in different soil profiles. The DHA was found to decline with depth and the maximum activity was recorded within 0–30 cm soil depth. Cropping systems and bio-climates significantly (p < 0.01) influence the DHA in soil. Significantly (p < 0.01) higher DHA was recorded in Sub-humid moist (SHm) bio-climate (2.45 μg TPF g− 1) followed by Semi-arid dry (SAd) (2.00 μg TPF g− 1) and the least in arid bio-climate (1.62 μg TPF g− 1). The average DHA in different bio-climates were in decreasing order of Sub-humid moist > Semi-arid dry > Sub-humid dry > arid. Legume-based cropping system recorded higher DHA (2.32–2.88 μg TPF g− 1) followed by cereal-based cropping system (1.29–2.82 μg TPF g− 1). The average DHA in different cropping systems were in decreasing order of legume > cereals > cotton > sugarcane. The comparisons of DHA in different soils indicated significant differences (p < 0.01) between the soil sub groups. High management practices found to significantly increase DHA (2.15 μg TPF g− 1) compared to low management (1.78 μg TPF g− 1), whilst no significant differences were found in DHA between irrigated and rainfed system.

► Dehydrogenase activity declined with increase in soil depth in all the BM spots.
► Bio-climates, cropping systems and management levels highly influence DHA in soil.
► DHA in different bio-climates were in decreasing order of SHm>SAd>SHd>arid.
► Legume-based cropping systems recorded higher DHA compared to cereals.
► No significant differences were found in DHA between irrigated and rainfed system.