Effect of long-term fertilization on organic matter, total nitrogen and microbe characteristic of black soil

摘要

The changes in black soil organic matter, total nitrogen and microbe characteristics were studied for a long-term fertilization experiment which has been on-going for 27 years. Results showed that the treatment of organic manure plus chemical fertilizer increased the content of soil organic matter and total nitrogen, while the no fertilizer treatment had the lowest contents. Soil pH declined under long-term chemical fertilizer and the addition of organic manure decreased pH slowly as well. The addition of chemical fertilizer increased the number of cellulose utilizing bacteria. The number of N utilizing microbes increased significantly under the addition of organic manure plus chemical fertilizer with the number of arnmonifying bacteria being most affected.