关键词: 土壤水分含量, 土壤水分含量

Abstract: In order to determine the change of soil enzyme activities and soil labile organic carbon contents in Cunninghamia lanceolata plantation after thinning in a short time. Soil enzyme activity, soil labile organic carbon and soil carbon management index were studied in 3 thinning intensities (unthinning, moderate and heavy thinning) in C. lanceolata plantation in Kaihua County, Zhejiang Province. After 2 years thinning treatment, the activities of soil catalase, urease, phosphatase and invertase in 0-20 cm soil layers increased in the thinned treatments compared with unthinned treatment. The activities of these soil enzymes increased only in 0-10 cm soil layer in moderate thinning treatment, and which significantly increased in the 0-20 cm soil layers in heavy thinning treatment. Soil labile organic carbon contents in 0-20 cm soil layer increased in the thinned treatments, no significant differences were detected in soil profile for soil stable organic carbon contents. Soil carbon activity, carbon activity index, carbon index and carbon management index in 0-10 cm soil layer increased with increasing thinning intensity, soil carbon management index significantly increased in 10-20 cm soil layer in heavy thinning treatment compared with control. There were no significant differences among the three thinning treatments in soil enzyme activities, soil labile organic carbon contents or soil carbon management index below 20 cm soil layer. Four soil enzymes presented a significant and positive correlation with soil labile organic carbon, and soil carbon management index. These results indicated that: soil enzyme activities and soil labile organic carbon contents in shallow soil layer were enhanced in C. lanceolata plantation after 2 years thinning treatment, which would lead to a release of stored soil carbon.