中国水土保持科学2018,Vol.16Issue(1):46-55,10.DOI:10.16843/j.sswc.2018.01.006
黄土丘陵区土壤水分空间分布与环境因子的关系
Spatial distribution of soil moisture and its relationships with environmental factors in loess hilly region
摘要
Abstract
[Background] Soil moisture content is one of the key factors affecting various ecosystem processes,especially for semi-arid and arid areas.At present,few researches are focused on the spatial distribution of soil moisture content and its relationships with multi-environmental factors in large scale,which is of significance in planning ecological vegetation in soil and water conservation.In this study,we aimed to investigate the spatial distribution of soil moisture content in the loess hilly region and further analyze its relationships with other environmental factors.[Methods] The study was carried out in Yanhe watershed,north of the Loess Plateau.Ten sample areas were chosen by using nature separation method.We investigated the characteristics of soil moisture and 8 environmental factors (annual average rain,annual average evapotranspiration,annual average temperature,elevation,aspect,slope,slope position,and landuse) at each sample area.Firstly,we analyzed the distribution of soil moisture in different sample areas based on sampling analysis and statistical analysis.Then,the redundancy analysis (RDA) was used to determine the key factors leading to these differences.[Results] Soil moisture content in Wanhuashan was significantly higher than that in other sample areas (P < 0.05).While,the lowest soil moisture content was observed in Liandaowan (P < O.05).Moreover,the Yanhe watershed can be divided into four water gradients by moisture content of 14.64%,12.36%,10.32%,and 8.76%,which was in decreasing trend from south to north.Soil moisture content of Gaoqiao,Xiannangou and Zhaoanzhen increased with soil depth,while soil moisture content of the other seven sample areas increased at first and then decreased.Significant environmental gradient were observed in the spatial distribution of soil moisture content.All sampling sites were plotted out 3 groups by RDA.The dominant factor of soil moisture content in the southeastern,southwestern and northern Yanhe watershed were annual average temperature,annual average rain and annual average evapotranspiration,respectively.Redundancy analysis showed that annual average evapotranspiration and annual average rain were the dominant factors influencing soil moisture content spatial distribution pattern in the whole watershed region.Topography and landuse had no significant effect on soil moisture content distribution in the Yanhe watershed.[Conclusions] The comprehensive effect of environmental factors led to the spatial gradient of soil moisture content.These results are essential in explaining the spatial distribution of soil moisture content and its relationships with environmental factors in the loess hilly region.This study provides a theoretical basis for vegetation restoring and reconstructing in the Loess Plateau.关键词
土壤水分/环境梯度/冗余分析/黄土丘陵区Key words
soil moisture/environmental gradient/redundancy analysis/loess hilly region分类
农业科技引用本文复制引用
郭美丽,焦峰,薛超玉..黄土丘陵区土壤水分空间分布与环境因子的关系[J].中国水土保持科学,2018,16(1):46-55,10.基金项目
国家自然科学基金“黄土区人工林地下生产力及化学计量生态学研究”(31370455) (31370455)