不同土壤水分对青藏高原高寒草甸土壤酶活性的影响

Effects of Different Soil Moisture on Soil Enzyme Activities in Alpine Meadow of Qinghai-Tibet Plateau

为探究全球气候变化导致的青藏高原降水增加对高寒草甸土壤酶活性的影响,本试验根据研究区域近21年植被生长季的年均降水量(W)设置3种增水处理,即增水50%W(+50%W),25%W(+25%)和不增水处理(CK),来研究不同水分添加对青藏高原高寒草甸土壤理化性质和酶活性的影响。结果表明:随着水分添加量的增加,高寒草甸土壤有机质(SOM)、总氮(TN)、全磷(TP)、速效氮(NH4^(+)、NO3^(-))明显提高;水分添加明显促进β-1、4-葡萄糖苷酶(βG)、β-N-乙酰葡萄糖胺糖苷酶(NAG)活性提高,但磷酸酶(aP)活性却随水分添加量的增加而减小。冗余分析(RDA)结果表明,土壤酶活性与土壤理化性质,特别是土壤速效养分含量,显著相关。

To explore the effect of the precipitation increasing caused by global climate change on soil enzyme activity in Alpine meadow of Qinghai-tibet plateau,in this experiment,three kinds of water treatment were designed according to an average annual rainfall of 21 years in vegetation growing season in the research areas,which increases the water of 50%,increases the water of 25%,and control treatment(CK)for study the effect of different water added on soil physical and chemical properties and enzyme activity in Alpine meadow of Qinghai-tibet plateau.The results showed that the soil organic matter(SOM),total nitrogen(TN),total phosphorus(TP),available nitrogen(NH4^(+),NO3^(-))in Alpine meadow significantly increased with the increasing of water addition.The activities ofβ-1,4-glucosidase(βG)andβ-N-acetylglucosamine glycosidase(NAG)were significantly increased by water supplementation,but the activity of phosphatase(AP)was decreased with the increasing of water supplementation.The redundancy analysis(RDA)results showed that soil enzyme activities were significantly correlated with soil physical and chemical properties,especially the content of soil available nutrients.