黄土高原不同林地土壤水分特征及影响因子通径分析  

Characteristics of soil moisture and path analysis of influencing factors on different forest lands on the Loess Plateau

作　　者：胡波[1] 陈丽华[1,2] HU Bo;CHEN Lihua(School of Soil and Water Conservation,Beijing Forestry University,100083,Beijing,China;National Field Research Station of Forest Ecosystem in Jixian County,042200,Jixian,Shanxi,China)

机构地区：[1]北京林业大学水土保持学院,北京100083 [2]山西吉县森林生态系统国家野外科学观测研究站,山西吉县042200

出　　处：《中国水土保持科学》2021年第1期79-86,共8页Science of Soil and Water Conservation

基　　金：国家重点研发项目“黄土残塬沟壑区水土保持型景观优化与特色林产业技术及示范”(2016YFC0501704)。

摘　　要：通过野外实测数据,研究土壤水分特征,用通径分析明确不同影响因子对土壤含水量的直接和间接作用。在黄土高原研究区,分别在油松林、刺槐林和苹果林样地设立土壤水分动态观测点,用Water Scout SM 100 Sensor-6ft水分探头在2018年4—10月植被生长季观测不同土层的土壤体积含水量,同年8月,在不同林地分层进行土壤取样,测定土壤理化性质。结果表明:1)观测林地土壤含水量之间存在显著差异(P <0.05),苹果林土壤含水量总体高于刺槐林和油松林;2)研究区不同林地土壤水季节变化趋于一致,总体呈先上升后下降趋势,生长季土壤总贮水量苹果(1 460.38 mm)>油松(988.02 mm)>刺槐(844.66 mm);3)土壤理化性质和土壤水分变化有显著的相关性,通过通径分析得出:影响最显著的因子为0.050~0.002 mm土壤颗粒含量,其决策系数为9.825;密度对其有较大的间接作用;有机质和2.000~0.050 mm土壤颗粒含量对土壤含水量有极显著的抑制作用,其决策系数分别为-2.669和-5.645。通径分析适用于土壤水分影响因子分析。研究结果可为黄土高原地区林地树种选择及生态环境管理提参考。[Background] Due to the influence of natural and human factors,soil erosion is a serious problem on the Loess Plateau. A large amount of vegetation has been planted on this plateau via various soil and water conservation measures and ecological restoration. At the same time,vegetation growth consumes a high amount of soil moisture. Soil-water deficit restricts vegetation growth and further affects the ecological environment improvement. The Caijiachuan watershed selected in this paper represents typical characteristics of the Loess Plateau. This study not only analyses the pattern of soil moisture change and influencing factors, but also measures the applicability of the path analysis method.[Methods]In the study area of the Loess Plateau,we set up soil moisture dynamic observation points in the Pinus tabuliformis( PT), Robinia pseudoacacia( RP), and Malus domestica( MD) plots respectively,using the WaterScout SM 100 Sensor-6 ft to observe the soil volumetric moisture content in different soil layers from April to October 2018. In the August of the same year,we sampled the undisturbed soil with a ring knife and obtained soil samples from different forest lands to determine the physical and chemical properties of the soil. The variation in soil moisture is influenced by many factors,and path analysis was used to analyze the relationship among these factors. [Results]1) There was a significant difference in moisture contents of the sampled soils( P < 0. 05). The soil moisture content of the MD forest was generally higher than that of the RP forest and PT forest. 2) The seasonal changes in soil moisture in different forests in the study area tended to be consistent and generally increased first and then decreased. The total soil moisture storage in the forests during the growing season was in the following order: MD( 1 460. 38 mm) > PT( 988. 01 mm) > RP( 844. 67 mm). 3) There was a significant correlation between soil physicochemical properties and the changes in soil moisture. Through path analysis,the most signifi

关 键 词：土壤含水量 动态变化 通径分析 不同林地 黄土高原 

分 类 号：S152.7[农业科学—土壤学]