落叶松人工林土壤磷形态、磷酸酶活性演变与林木生成关系的研究

采用对比分析方法 ,揭示了不同发育阶段落叶松人工林根际与非根际土壤磷形态和磷酸酶活性的演变规律 ,阐释了土壤磷形态、磷酸酶活性与林龄的关系 ,建立了土壤磷形态、有机质、速效钾、水解氮与林木生长量关系的逐步回归模型。结果表明 :落叶松人工林不同发育阶段根际土壤磷形态、磷酸酶活性变化存在着明显的规律 ,有效磷含量、O -P含量、全磷含量、有机磷含量、酸性磷酸酶活性随林龄的增加而下降 ,无机磷总量、Ca -P含量、Fe-P含量随林龄的增加而增加。非根际土壤Ca -P含量随林龄的增加而显著增加 ,酸性磷酸酶活性随林龄增加而明显下降。各年龄阶段间除非根际土壤酸性、中性磷酸酶活性和Al-P含量的差异没有达到显著水平外 ,根际与非根际土壤其它成分的差异均达到极显著和显著水平。中龄林土壤Fe-P含量、近熟林土壤有效磷含量、Fe -P含量和酸性磷酸酶活性、成熟林土壤有效磷、Ca -P含量和酸性磷酸酶活性出现非根际土壤大于根际土壤 ,其它成分均为根际土壤大于非根际土壤。不同发育阶段影响林木生长量的主要土壤磷形态是全磷、有机磷、有效磷、无机磷总量、Ca -P和Fe -P。

The Succession of Various Types of Phosphorus, Phosphatase Activity, and the Relationship with the Tree Growth in Larch Plantations

By the method of comparison and analysis, the succession pattern of phosphorus and phosphatase activity in rhizosphere and non|rhizosphere soil in larch (Larix olgensis) plantations was revealed. The relationship between phosphorus forms, phosphatase activity, and stand age was explained. Stepwise regression models among phosphorus forms, organic matter, rapidly available K, hydrolyzable N and tree growth were established. The results showed: when stand age increased, the content of available phosphorus, O-P, total P, organic P, acid phosphatase activity in rhizosphere soil decreased significantly,the content of inorganic P, Ca-P and Fe-P in rhizosphere soil increased significantly. The content of Ca-P and the acid phosphatase activity in non|rhizosphere soil increased and decreased respectively with stand growing.Except for acid phosphatase activity, neutral phosphatase activity, and the content of Al-P in non|rhizosphere soil, the difference of other components in rhizosphere and non|rhizosphere soil reached greatly significant level and significant level between different development stages. The content of Fe-P in half|mature stand, available P, Fe-P, and acid phosphatase activity in near mature stand, available P, Ca-P, and acid phosphatase activity in mature stand in non|rhizosphere soil was more than that in rhizosphere soil, the contents of other components in rhizosphere soil were more than those in non|rhizosphere soil. Main types of phosphorus which affecting tree increment in different stages were total P, organic P, available P, total inorganic P, Ca-P and Fe-P.