Effects of Long-term Fertilization on Soil Organic Nitrogen Profile Distribution in Vegetable Soil

摘要

The long-term fertilization was taken as the research object in this experiment.This experiment studied the forms and compositions of soil organic nitrogen (hi) in vegetable-soil.The content of total N and organic N fractions decreased with increasing layer depth,but the proportion of organic N fractions accounting the total N didn't have obvious rules.Extent of decreasing content of organic nitrogen was different for different fertilization ways.Compared with single chemical fertilizer,manure application treatment was still faster than that of single chemical fertilizer treatment on extent of decreasing content of total N and organic N,but the content of total N and organic N was higher than that of single chemical fertilizer treatment.The ammonia nitrogen content of all treatments in the 20-40cm soil layer significantly decreased and decreased slightly in other soil; The amino sugar N content of manure application treatment increased significantly,but the extent of increasing gradually decreased with soil depth,and there is no significant difference among all treatments of 40 to 60 cm soil depth; about extent of decreasing content of unidentified hydrolysable N,manure applying treatment was higher than that of single chemical fertilizer treatment in the 10-20cm soil depth.