植被群落演替对土壤饱和导水率的影响

    Effect of syndynamic on soil saturated hydraulic conductivity

    • 摘要: 土壤饱和导水率是表征土壤入渗能力的重要参数,对不同土地利用类型反应敏感。为了揭示植被演替对土壤剖面上饱和导水率的影响规律,采用恒定水头法测定了天童林区155 a植物群落演替序列60 cm深土壤剖面上的饱和导水率。结果表明,不同演替阶段饱和导水率均随土壤深度增加迅速降低,在0~20 cm土层内,各演替阶段饱和导水率均存在极显著差异,0~60 cm土层内饱和导水率的平均值从裸地、石栎+檵木灌丛、马尾松林、木荷+马尾松林、木荷林到栲树林升高极为显著,植物群落演替到灌丛阶段,平均饱和导水率已与裸地存在显著差异,演替到栲树顶极群落达到最高3.28 mm/min;土壤体积质量、非毛管孔隙度和粉粒含量为影响饱和导水率的主要因子;土壤有机质随演替进展而增加,与饱和导水率呈极显著正相关。植被演替能显著提高土壤饱和导水率,天童常绿阔叶林区土壤高的饱和导水率是坡面径流少见的主要原因。

       

      Abstract: Saturated hydraulic conductivity (Ks) is a critical parameter affecting soil infiltration capacity and water flow, and Ks is sensitive to different land use patterns. To study the effect of vegetation secondary succession on Ks, the experiment was conducted in the evergreen broad-leaved forests with the succession chronosequences of 155 years in Tiantong National Forest Park, Zhejiang Province, Eastern China. Ks was measured by the constant-hydraulic head method along 60 cm soil profiles under the different vegetation succession stages. The results showed that values of Ks reduced quickly with soil depth under different succession stages. There were significant differences of Ks among all the succession stages in the 0–20 cm soil depth. The average Ks in the 60 cm soil profile significantly increased from the bare land, Lithocarpus glaba + Laroptahon chenese shrub, Pinus massonian forest, Schima superba + Pinus massoniana forest, Schima superba forest to Castanopsis fargesii forest. In the shrub stage, the average Ks had showed significant difference to bare land. In the Schima superba forest, the average Ks had increased significantly. When the succession went into the climax stage, the average Ks reached maximum value (3.28 mm/min). Soil bulk density, non-capillary porosity, and silt content were the key factors which affected Ks. Soil organic matter (SOM) was also increased with vegetation succession and positively correlated to Ks. This study suggested that Ks was significantly improved with the forest succession process in Tiantong National Forest Park. High values of Ks could explain that why the overland flow was rarely occurred in this region.

       

    /

    返回文章
    返回