补播对退化高寒草甸土壤性质及酶活性的影响

Effect of Replanting on Soil Properties and Enzyme Activities in Degraded Alpine Meadows

退化草地修复不仅是植被的修复,更重要的是土壤状况的修复。为明确补播对退化高寒草甸土壤修复效应,对青藏高原青海草地早熟禾补播草地土壤碳氮磷等化学性质及脲酶、磷酸酶和蔗糖酶活性进行了研究。结果显示:高寒草甸中度退化草地实施补播后,表层土壤酸碱度显著降低;土壤含水量、有机碳、全氮、全钾、硝态氮、碳氮比及土壤脲酶和磷酸酶活性无明显变化;土壤全磷、铵态氮、速效磷、速效钾和土壤蔗糖酶活性显著升高。草地土壤酶活性与土壤铵态氮、全钾及土壤碳氮比无关,补播改变了土壤酶活性与土壤全氮、硝态氮、全磷、速效磷和速效钾的调控关系。

The restoration of degraded grassland is not only the restoration of vegetation,but also the restoration of soil condition.To clarify the soil remediation effect of replanting on degraded alpine meadow,the soil chemical properties such as soil carbon,nitrogen and phosphorus and the enzyme activities of urease,phosphatase and sucrase in Kentucky bluegrass replanting grassland were studied on the Qinghai-Tibetan plateau.The results showed that the topsoil pH of the moderately degraded grassland decreased significantly in replanting grassland,and there were no significant changes in soil water content,organic carbon,total nitrogen,total potassium,nitrate nitrogen,carbon-nitrogen ratio and soil urease and phosphatase activities between the two treatments.While the soil total phosphorus,ammonium nitrogen,available phosphorus,available potassium and soil sucrase activity increased significantly in replanting grassland.The soil enzyme activities had not correlation with soil ammonium nitrogen,total potassium and soil carbon-nitrogen ratio.Replanting changed the regulation relationship between soil enzyme activities and soil total nitrogen,nitrate nitrogen,total phosphorus,available phosphorus and available potassium.