黄土丘陵区不同年限柠条林地土壤质量变化

Dynamics of Soil Quality in a Loess Hilly Area Grown with Caragana Korshinskii

在野外调查和室内分析的基础上，探讨了0、10、22、26和30a时间序列柠条林地土壤物理、化学及酶活性的动态变化。结果表明：柠条林可提高土壤粘粒、粉粒含量，10-26a土壤容重显著降低；除全磷表现为减少趋势外，随生长年限延长，柠条林地有机质、全氮、硝态氮、铵态氮、速效磷和速效钾含量均呈现增加趋势；土壤蔗糖酶、碱性磷酸酶、脲酶和过氧化氢酶活性随柠条生长年限增加呈增加趋势，但各种酶表现最佳状态的时间不同，且蔗糖酶和碱性磷酸酶对柠条林地土壤变化的敏感性高于脲酶和过氧化氢酶。

Based on a field investigation and an indoor analysis, physical characters, nutrition and enzyme activity of soils collected from a loess hilly area were studied in the presence of 0,10,22,26 and 30 years Caragana korshinskii, in order to assess effects of soil quality by an age sequence of 0-30 years C. The results showed that the shrub （ C. korshinskii） could improve contents of both soil clay and soil silt, and lower bulk density by the grown plant with 10 to 26 years. It could also increase contents of soil organic matter, total nitrogen, nitrate, ammonium, rapidly available phosphorus and potassium, improve soil enzyme activity as years. However, optimal condition for soil enzymes activity was discovered at different periods, h was also found that sucrase and alkaline phosphate activities were more sensitive than either catalase or urease.