三峡库区不同林草治理措施下土壤入渗特征研究

Characteristics of Soil Water Infiltration Under Different Biological Regulation Measures in Three Gorges Reservoir Region

坡地是三峡库区土壤侵蚀的主要地类,其利用方式与水土流失的关系研究是三峡库区水土流失综合治理与生态环境建设中的重要基础科学问题.在重庆开县选择栾树+黄花槐、封山育林、经济林3种林草治理措施(以裸地为对照),对土壤入渗特征及其影响因子进行了研究.结果表明:(1)3个土壤入渗特征值在不同林草治理措施下变化较大,其大小顺序主要呈初渗率,平均入渗率和稳定入渗率的规律.初渗率、稳定入渗率和平均入渗率在不同土层深度均以裸地的值最小,其平均值分别为1.22,0.141和0.462mm/min;(2)通过主成分分析法,得出土壤渗透性能综合判断值(F)的综合方程,综合评价了不同林草治理措施土壤渗透性优劣,其大小顺序表现为:栾树+黄花槐,封山育林,经济林和裸地.(3)Pearson相关分析结果表明,不同林草治理措施与裸地的土壤渗透性与总孔隙度、非毛管孔隙度、饱和含水量及土壤有机质含量呈极显著(p<0.01)或者显著正相关(p<0.05),与土壤容质量呈极显著(p<0.01)或显著负相关(p<0.05).(4)对土壤入渗过程模拟得出通用经验方程是用于描述不同林草治理措施下土壤入渗过程的最优模型.

The study on the relationship between biological regulation measures and soil and water loss is of great significance to soil and water conservation and ecological reconstruction of the environment in Three Gorges Reservoir Area. Soil water infiltration was measured under 4 kinds of biological regulation meas-ures （Koelreuteria bipinnata ＋ Cassia suffruticasa, closed forest, economic forest and control plot） in Kaixian county of Chongqing and the measured data were compared and analyzed. Large variations were found among e 3 infiltration eigenvalues （initial infiltration rate, average infiltration rate and stable infil tration rate） in the 4 treatments （3 biological regulation measures and bare land）, bei tial infiltration rate 〉 average infiltration rate 〉 stable infiltration rate. The control ng pl in the order of ini ot （bare land） had the minimum value of initial infiltration rate, average infiltration rate and stable infiltration rate in differ- ent soil depth, being 1.22 mm/min, 0. 141 mm/min and 0. 462 mm/min, respectively. Based on principal component analysis, a comprehensive equation was established for the integrated estimation of the biologi-cal regulation measures for soil permeability values （F）, by which the soil permeability of different biolog-ical regulation measures was arranged in the order of K. bipinnata ＋ C. suffruticasa 〉 closed forest 〉 e-conomic forest ） control plot. Pearson correlation analysis showed that logical regulation measures and the control plot was in a significant or hig per hly meability under the three bio significant positive linear cor relation （p〉0.01 or p〉0.05 ） with soil total porosity, non-capillary porosity, saturated water content and the organic matter content, and in a significant or highly significant negative linear correlation （p〈 0.01 or p〈0. 05 ） with soil bulk density. The general empirical model obtained through the simulation of the soil infiltration processes was the best one to describe the soil infiltration processes of different biologi cal regulation measures.