人工草地土壤质量及土壤酶活性对利用年限的响应

Responses of soil quality and soil enzyme activities in artificial grassland to utilization years

摘要:

土壤质量能够敏感而准确地反映自然及人类活动导致的土壤环境动态变化。本研究以利用 5、13、24 a 的人工草地为对象，通过对土壤理化指标、土壤酶活性进行分析，探究人工草地土壤理化性质及土壤酶活性对利用年限的响应特征，以期为人工草地治理和可持续利用提供理论依据。结果表明：随着人工草地利用年限增加土壤有效磷、速效钾含量显著下降；随着人工草地利用年限增加土壤过氧化氢酶、脲酶、蔗糖酶活性均显著下降(P＜0. 05)；土壤过氧化氢酶和蔗糖酶活性与土壤质量有显著的相关性。得出土壤酶活性与土壤质量显著相关，人工草地在利用的第 5~13 年土壤酶活性升高，说明人工草地在利用初期土壤质量状况较好，但是当草地利用年限超过 13 年时土壤出现酸化，土壤酶活性降低，土壤中物质循环速率降低。

Abstract:

Soil quality can sensitively and accurately reflect the dynamic changes of soil environment caused by natural and human activities. In this study，the artificial grassland of 5，13 and 24 years was used as the object. The re‐ sponse characteristics of soil physical and chemical properties and soil enzyme activities of artificial grassland to the utilization years were investigated by analyzing soil physical and chemical indexes and soil enzyme activities of artifi‐ cial grassland，so as to provide theoretical basis for the management and sustainable utilization of artificial grassland. the results showed that the contents of available soil phosphorus and available soil potassium decreased significantly with the increase of artificial grassland utilization years. Besides，soil catalase，urease and sucrase significantly de‐ creased with the increase of artificial grassland utilization years (P＜0. 05). Further，soil catalase and sucrase were significantly correlated with soil quality. In conclusion，soil enzyme activities are significantly correlated with soil qual‐ ity. The soil enzyme activities of artificial grassland increase in the 5th to 13th year of utilization，indicating that the soil quality of artificial grassland is good in the early stage of utilization. However，when the utilization life of grass‐ land exceeds 13 years，soil acidification occurs，soil enzyme activities decrease，and the material recycling rate in soil decreases. The results can provide theoretical basis for sustainable utilization of artificial grassland.