Effects of vegetation restoration on the spatial distribution of soil moisture at the hillslope scale in semi-arid regions

Soil moisture is important for plant growth in semi-arid ecosystems. In this study, spatial variations in soil moisture at depths of 0-6 m on seven hillslopes of China's Loess Plateau planted with korshinsk peashrub were analyzed based on soil moisture observations. The objective of this study was to compare the spatial patterns in soil moisture in shallow and deep soil layers at the hillslope scale under the influence of large-scale vegetation restoration. The results showed that: (1) the topographic wetness index was positively correlated with soil moisture near the surface (0-1 m), but negatively correlated with soil moisture at depths below 2 m; and (2) the negative relationship was found between biomass and soil moisture content in deep layers. Soil moisture in shallow layers was more likely to be affected by topographic factors. However, comparisons of soil moisture at different slope positions indicated that the effect of topographic factors on the variability of deep soil moisture was altered, mainly because plants with different biomasses may differ in their consumption of soil water and thus cause greater spatial variations in deep soil moisture. The introduced vegetation may alter the spatial pattern of deep soil moisture influenced by topographic factors at the hillslope scale, and the biomass may have a determining role in the spatial variation of deep-layer soil moisture content. (C) 2014 Elsevier B.V. All rights reserved.

[1]  Bojie Fu,et al.  Spatial variability of soil moisture content and its relation to environmental indices in a semi-arid gully catchment of the Loess Plateau, China , 2001 .

[2]  Wei Wei,et al.  Response of temporal variation of soil moisture to vegetation restoration in semi-arid Loess Plateau, China , 2014 .

[3]  Günter Blöschl,et al.  Spatial correlation of soil moisture in small catchments and its relationship to dominant spatial hydrological processes , 2004 .

[4]  Liding Chen,et al.  Response of deep soil moisture to land use and afforestation in the semi-arid Loess Plateau, China , 2012 .

[5]  E. Vivoni,et al.  Vegetation controls on soil moisture distribution in the Valles Caldera, New Mexico, during the North American monsoon , 2008 .

[6]  M. Shao,et al.  The characteristics of soil water cycle and water balance on steep grassland under natural and simulated rainfall conditions in the Loess Plateau of China , 2008 .

[7]  Bojie Fu,et al.  Soil and water conservation on the Loess Plateau in China: review and perspective , 2007 .

[8]  P. Legendre,et al.  Spatial relationships between soil moisture patterns and topographic variables at multiple scales in a humid temperate forested catchment , 2010 .

[9]  B. Venkatesh,et al.  Analysis of observed soil moisture patterns under different land covers in Western Ghats, India , 2011 .

[10]  Marco Borga,et al.  Hillslope scale soil moisture variability in a steep alpine terrain , 2009 .

[11]  V. Castillo,et al.  Spatial patterns and temporal stability of soil moisture across a range of scales in a semi‐arid environment , 2000 .

[12]  Yolanda Cantón,et al.  Temporal and spatial patterns of soil moisture in semiarid badlands of SE Spain , 2004 .

[13]  M. Shao,et al.  Soil desiccation in the Loess Plateau of China , 2008 .

[14]  Chantal Gascuel-Odoux,et al.  THE INFLUENCE OF TOPOGRAPHY ON TIME AND SPACE DISTRIBUTION OF SOIL SURFACE WATER CONTENT , 1997 .

[15]  Jeffrey J. McDonnell,et al.  On the interrelations between topography, soil depth, soil moisture, transpiration rates and species distribution at the hillslope scale , 2006 .

[16]  M. Shao,et al.  Temporal stability of soil water storage in diverse soil layers , 2012 .

[17]  I. Rodríguez‐Iturbe,et al.  Ecohydrology of water-controlled ecosystems , 2004 .

[18]  M. Shao,et al.  Variability and pattern of surface moisture on a small-scale hillslope in Liudaogou catchment on the northern Loess Plateau of China , 2008 .

[19]  Günter Blöschl,et al.  Observed spatial organization of soil moisture and its relation to terrain indices , 1999 .

[20]  B. Fu,et al.  Effects of landscape restoration on soil water storage and water use in the Loess Plateau Region, China , 2010 .

[21]  Stephen P. Hubbell,et al.  Drought sensitivity shapes species distribution patterns in tropical forests , 2007, Nature.

[22]  Yu Zhang,et al.  Soil moisture response to environmental factors following precipitation events in a small catchment , 2014 .

[23]  Günter Blöschl,et al.  On the spatial scaling of soil moisture , 1999 .

[24]  Kelly K. Caylor,et al.  Spatial variation in vegetation structure coupled to plant available water determined by two-dimensional soil resistivity profiling in a Brazilian savanna , 2007, Oecologia.

[25]  Delphis F. Levia,et al.  Soil moisture: A central and unifying theme in physical geography , 2011 .

[26]  Baoyuan Liu,et al.  Soil moisture of different vegetation types on the Loess Plateau , 2009 .

[27]  Peter A. Troch,et al.  Hysteresis of soil moisture spatial heterogeneity and the “homogenizing” effect of vegetation , 2009 .

[28]  A. Western,et al.  Seasonal and event dynamics of spatial soil moisture patterns at the small catchment scale , 2012 .

[29]  Willem J. D. van Leeuwen,et al.  Quantifying the influence of deep soil moisture on ecosystem albedo: The role of vegetation , 2014 .

[30]  M. Shao,et al.  A comparison of fine root distribution and water consumption of mature Caragana korshinkii Kom grown in two soils in a semiarid region, China , 2009, Plant and Soil.

[31]  Yun-qiang Wang,et al.  A preliminary investigation of the dynamic characteristics of dried soil layers on the Loess Plateau of China , 2010 .

[32]  G. Sun,et al.  Potential water yield reduction due to forestation across China , 2006 .

[33]  K. Price.  Effects of watershed topography, soils, land use, and climate on baseflow hydrology in humid regions: A review , 2011 .

[34]  Marc Voltz,et al.  Spatio-temporal distribution of soil surface moisture in a heterogeneously farmed Mediterranean catchment , 2006 .

[35]  B. Fu,et al.  Hydrologic feasibility of artificial forestation in the semi-arid Loess Plateau of China , 2011 .

[36]  Wei Wei,et al.  Spatial variations of shallow and deep soil moisture in the semi-arid Loess Plateau, China , 2012 .