Fertility Quality Assessment of Soda Alinization Steppe Soil with Different Utilization Types in the West of Jilin Province

Different land utilization methods have important effects on soil fertility quality.Five different land utilization methods of saline steppe soil in the west of Jilin province were selected,including grazing grassland,fencing grassland,tillable,new paddy field and long-term cultivate paddy field.The main nutrients of the soils were determined.Soil fertility quality and soil fertility degradation were determined by using quantitative analysis method of soil quality index(QI) and soil deterioration index(DI).The results showed that the QI of grazing grassland is 22.56%;the fencing grassland is 66.56%;the tillable field is 11.90%;the new paddy field is 77.11%;the long-term cultivate paddy field is 82.34%.Using the DI of grazing grassland as reference,the DI of tillable field is negative,the others are positive.The DI of paddy field and the fencing grassland are higher.The results showed that the values of paddy field and enclosure grassland were higher whereas grazing grassland and tillable were lower,tending to degenerate.