Effect of Soil Drying and Rewetting on Nitrogen Mineralization from Soil Amended with Organic Matters

Decomposition rate of various organic matters in soil depends on their intrinsic qualities, environmental condition specially temperature and moisture as well as size, diversity and activity of soil microorganisms. Soil water content variation caused by drying and rewetting events constitute an environmental factor that may have an important effect on N mineralization. In the future, many regions of the globe may experience higher mean annual temperatures and greater intra-annual variability in the timing of precipitation events. Under these scenarios, surface soils may experience more frequent drying and rewetting events. However, limited data are available on the effect that drying and rewetting may have on N mineralization from added organic matter. With this background the present study was undertaken with the specific objective to study the effect of drying and wetting of soil on nitrogen mineralization of organic matters under laboratory condition. After 10 days of drying that nitrogen mineralization for all the organics were significantly less as compared to constant moisture treatment. The difference of net nitrogen mineralization was more in tannery waste than other two. After second drying also nitrogen mineralization were more in constant moisture treatment for all the organics. It was also revealed that reduction of net mineralization was more after second drying.