CARBON DIOXIDE EVOLUTION AND ENZYMATIC ACTIVITIES OF SOIL UNDER DIFFERENT LAND USE PRACTICES LOCATED NEAR BHAWANIPATNA TOWN IN ODISHA, INDIA.

Soil respiration and enzyme activities reflect the biochemical functioning and nutrient cycling in soil. Knowledge regarding them can be useful in describing changes due to land use, land cover system and defining management strategies for restoring soil ecosystem functioning. In the present study, carbon dioxide evolution and enzymatic activities in soil were studied in four land use systems viz. sugarcane field, rice field, forest land and pasture land from Sujanpur village near Bhawanipatna town of Kalahandi, Odisha, India during April 2013 to November 2013. The study showed that carbon dioxide evolution and protease activity is decreasing in the order: Forest land > Rice field > Pasture land > Sugarcane field. Invertase activity was found to be highest in rice field (8.93 μg glucose/g dry wt./h) with the lowest value in pasture land (6.71 μg glucose/g dry wt./h) while, urease activity was found to be highest in agricultural land i.e. rice and sugarcane field (0.63 and 0.60 μg urea/g dry wt./h respectively) than in pasture (0.49 μg urea/g dry wt./h) and forest land (0.39 μg urea/g dry wt./h). Phosphatase (acid and alkali) and dehydrogenase activity was maximum in forest (1.04, 0.83 mg PNP/g dry wt./h and 57.53 μg TPF/g dry wt./h respectively) and minimum in pasture land (0.61, 0.38 mg PNP/g dry wt./h and 48.68 μg TPF/g dry wt./h respectively). The result however, showed insignificant variation in carbon dioxide evolution and enzyme activities with respect to different land use practices and hence confirm a very slow degradation of soil quality till today from the course of transformation to agricultural land. [ABSTRACT FROM AUTHOR]