衡阳紫色土丘陵坡地不同恢复阶段土壤渗透性研究与评价

Research and Evaluation on Soil Infiltration Properties in Different Re-vegetation Stages on Sloping-land with Purple Soils in Hengyang

以典型的衡阳紫色土丘陵坡地植被不同恢复阶段为研究对象,采用空间代替时间序列方法,选用立地条件基本相似的草坡恢复阶段(Ⅰ)、灌草恢复阶段(Ⅱ)、灌丛恢复阶段(Ⅲ)与乔灌恢复阶段(Ⅳ),通过Spearman秩相关分析法与灰色关联度分析方法,对各植被恢复阶段土壤水分入渗特进行研究分析.结果表明:(1)不同植被恢复阶段土壤饱和导电率与土壤容重呈极显著负相关(p<0.01),与非毛管孔隙度呈现出极显著正相关(p<0.05),与粒径在2～0.25 mm的含量呈显著正相关(p<0.05);(2)选取各植被恢复阶段的初渗速率、稳渗速率、平均渗透率和渗透总量4项参数进行灰色关联分析,各植被恢复阶段土壤水分入渗特性灰色关联度依次为乔灌恢复阶段(Ⅳ)(0.730 03)>灌丛恢复阶段(Ⅲ)(0.686 02)>灌草恢复阶段(Ⅱ)(0.596 09)>草坡恢复阶段(Ⅰ)(0.560 09)>裸露地(CK)(0.414 03),乔灌恢复阶段(Ⅳ)在所研究的区域内具有较好的水分入渗性能;(3)Horton水分入渗模型拟合的相关系数R2值≥0.774,对所研究的区域的土壤水分入渗过程具有较好的适用性.图1,表6,参23.

By using the space series to replace time courses, four typical sample plots, grassplot （ I ）, frutex and grassplot（ Ⅱ） , frutex（Ⅲ ） , arbor and frutex（ Ⅳ） communities in similar and typical sites in the sloping-land with purple soils in Hengyang, standing for four different successive stages, were selected as the study objects to explore the soil infiltration characteristics of different restoration stages by Spearman and grey analysis. The results showed that： （ 1 ） The soil saturated hydraulic conductivity have significantly negative correlations with soil bulk density （p 〈 0.01 ）, non-capillary porosity and the con- tents of 2 - 0.25 mm are positive correlated with the soil saturated hydraulic conductivity （p 〈 0.05 ） ; （2） Based on the initial infiltration rate, stable infiltration rate, average infiltration rate and cumulative in- filtration which are important parameters determining soil infiltration characteristic, the results from grey relational grade analysis show that the values of grey relational grade in different restoration stages took turns as arbor and frutex （ IV ） （ 0. 730 03 〉 frutex （Ⅲ ） （ 0. 686 02 ） 〉 frutex and grassplot （ Ⅱ ） （ 0. 596 09 ） 〉 grassplot （ I ） （0.560 09 ） 〉 barren （CK） （0.414 03 ）, arbor and frutex （ IV ） has the bet- ter infiltration capability in restoration stages ; （ 3 ） The fitting effect of Horton infiltration model on soil in- filtration process in each plot was good （R2〉10. 774）, which had good applicability. 1 fig. ,6tabs. , 23refs.