杉木连栽地营造不同混交林后的土壤生化特性及土壤肥力的研究

Studies on the Enzyme Activities and Fertilities of Soil in Various Mixtures Woodland after Chinese-fir Repeated Plantation

本文通过对杉木连栽多代林地及连栽地营造不同类型混交林后林地的上壤化学性状和土壤生化特性的比较研究,探讨杉木连栽多代的林地营造不同混交林后土壤酶活性及化学性状的变化趋势,土壤酶活性与土壤养分含量之间的相关性。试验结果表明:在杉木连栽多代后营造不同类型混交林,土壤的营养元素含量有显著的增加,以有机质增加最为显著,土壤的生化活性除了个别的酶外,不同类型的混交林显著比多代的杉木纯林高,其中以柳杉×薄姜木为最佳;各种土壤酶活性与土壤化学性状关系密切,单相关系数可达0.3452—0.9745,复相关系数0.8710—0.9745,可用土壤酶活性作为评价杉木连栽林地土壤改良中土壤肥力变化的指标之一;综合土壤酶活性及土壤化学性状进行聚类分析,表明杉木连栽后营造成不同类型的混交林,均能提高土壤肥力,有良好的改土作用,本研究中,以柳杉×薄姜木最为理想。

In this paper, some biochemical activities and chemical properties of the soils in the various mixtures woodlands after Chinese-fir repeated plantation were studied. The results showed that: ( 1 ) the enzyme activities and nutrient content of the soils in the various mixtures after Chinese-fir repeated plantation were-increasing markly. It was suggested that cultivated various mixtures after Chinese-fir repeated plantation is a practical biological measures to improve the soil condi tions of Chinese-fir repeated plantation woodlands. ( 2 ) statistical test indicated significant positive correlations between the enzyme activities of Catalase, Urease, Proteinase, Neutral-or Acidphosphatase, Invertase and Peroxidase(except Polyphend oxidase)with soil fertility. These correlation coefficients all reached the least significant levels ( PO. 01 or PO. 05). So soil enzyme activities could be used as an importtant index for evaluation of soil fertility.