林地土壤酶活性季节动态

Dynamics of Enzyme Activities of Soils in Repeated Plantation of Chinese-fir Woodland

我省杉木连栽林地土壤酶活性具有显著的季节性变化,多数酶活性春季开始上升,夏、秋季达最高,冬季下降至最低;同时,土壤酶活性和土壤的营养元素含量与杉木年阶段发育有密切关系,杉木生长发育最旺盛季节,需要养分最多时期,土壤酶活性也最为活跃;土壤酶活性和土壤营养元素含量的年均动态表现为一代杉木林>二代杉木林,或三代杉木林。

Some biochemical activities and chemical properties of the soils in the repeated plantation of Chinese-fir woodland were studied in 1987-1988. The results indicate that: biochemicalac-tivities of the soils exhibit an apparent seasonal change ,most enzyme activities begin to rise in spring, reach the maxium during May to September,and return to the minimum in winter . The activities of soil enzymes and the content of soil nutrients are closely related to the yearly growth of Chinese-fir at different stages. The average annual activities of soil enzymes and content of soil nutrients are as follows; the first rotation > the second rotation /the third rotation.