选取晋南典型丘陵沟壑区退耕年限为17,13,9和4年的人工刺槐林作为研究对象,对土壤养分含量进行测定分析,研究其含量变化。结果表明:1)相同土层深度下,刺槐林随退耕年限增加,土壤pH总体呈降低趋势。2)不同退耕年限刺槐林,其土壤氨氮含量随土层深度增加均呈现增加的趋势,总体表现为差异显著;不同退耕年限刺槐林同一土层深度下比较,土壤氨氮含量随退耕年限的增加有显著降低的趋势。3)不同退耕年限相同土层深度下刺槐林的速效磷,全氮和有机质含量随年限增加均有所增加。4)相同土层深度下刺槐林的硝氮,速效钾和全磷含量随退耕年限增加呈现降低的趋势。种植刺槐林可有效改良土壤养分状况,对土壤改善与养分保持具有积极作用。

This paper adopts artificial locust forests with 17,13,9 and 4 converted years in typical hilly and gully areas of southern Shanxi Province as the research objects to analyze the soil nutrient content and study its content changes.The results show that:1) at the same soil depth,locust forest show a decreasing trend and significant difference in soil pH with the increase of years of farming.2) The soil ammonia nitrogen content of Robinia pseudoacacia forest in different years of farming tends to increase in different soil depths,and the overall performance is significantly different.Compared with the same soil layer depth of Robinia pseudoacaciaforest in different years of farming,the content of ammonia nitrogen in soil decrease significantly with the increase of years of farming.3) The contents of available phosphorus,total nitrogen and organic matter of locust forest increase with the increase of years under the same soil depth in different years of farming.4) Nitrogen,available potassium and total phosphorus contents of locust forest at the same soil depth are prone to decrease with the increase of years of farming.It can be found that planting locust forest can effectively improve soil nutrient status and has a positive effect on soil improvement and nutrient maintenance.