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报道了鼎湖山季风常绿阔叶林和针阔叶混交林群落０～４０ｃｍ土层中细根（≤２ｍｍ和２～５ｍｍ）的现存量、死亡量、生产力和周转率，并比较了用“连续钻取土芯法”和“埋无根土柱法”来估算表层土（０～２０ｃｍ）细根生产力的差异。结果表明：在０～４０ｃｍ土层中，季风常绿阔叶林≤２ｍｍ和２～５ｍｍ细根现存量分别为６．５９ｔｈｍ－２和４．８１ｔｈｍ－２，死根比率各为２９．９％和２２．９％；针阔叶混交林≤２ｍｍ和２～５ｍｍ细根现存量分别为５．３５ｔｈｍ－２和４．２４ｔｈｍ－２，死根比率各为３４．４％和２４．０％。细根现存量的季节性变化不显著。季风常绿阔叶林细根年分解量、年死亡量和年净生产力分别为０．９０，１．５９，２．６５ｔｈｍ－２ａ－１（≤２ｍｍ）和０．４１，０．６３，１．２５ｔｈｍ－２ａ－１（２～５ｍｍ），针阔叶混交林的相应数值各为０．８０，１．４１，２．４２ｔｈｍ－２ａ－１（≤２ｍｍ）和０．３７，０．６２，１．２１ｔｈｍ－２ａ－１（２～５ｍｍ）。季风常绿阔叶林细根年周转率为０．５７（≤２ｍｍ）和０．３４次ａ－１（２～５ｍｍ），针阔叶混交林分别为０．６９（≤２ｍｍ）和０．３８次ａ－１（２～５ｍｍ）。
The existing stock, mortality, productivity and turnover rate of fine roots (≤2mm and 2 ~ 5mm) in 0-40cm soil layer of monsoon evergreen broad-leaved forest and coniferous-broad-leaved mixed forest in Dinghushan were reported. Continuous core drilling method “and” buried rootless column method "to estimate the difference of fine root productivity of surface soil (0 ~ 20cm). The results showed that in the 0-40 cm soil layer, the fine roots of ≤2 mm and 2 ~ 5mm in monsoon evergreen broad-leaved forest were 6.59thm-2 and 4.81thm-2 respectively, the dead root ratios were 29.9% And 22.9% respectively. The existing contents of fine roots of 2 mm and 2 ~ 5 mm in coniferous and broad-leaved mixed forests were 5.35thm-2 and 4.24thm-2, respectively, and dead root ratios were 34.4% and 24.0% respectively. The seasonal variation of fine root stock is not significant. In the monsoon evergreen broad-leaved forest, the fine root annual decomposition, annual mortality and annual net productivity were 0.90,1.59,2.65thm-2a-1 (≤2mm) and 0.41,0.63,1.25thm -2a-1 (2 ~ 5mm). The corresponding values of coniferous and broad-leaved mixed forest were 0.80,1.41,2.42thm-2a-1 (≤2mm) and 0.37,0.62,1 respectively. 21thm-2a-1 (2 to 5 mm). The annual rate of fine roots in monsoon evergreen broad-leaved forest was 0.57 (≤2mm) and 0.34 times a-1 (2 ~ 5mm) respectively. The coniferous and broad-leaved mixed forests were 0.69 (≤2mm) and 0.38 times a-1 (2 ~ 5mm).