Soil water content and temporal stability in an arid area with natural and planted grasslands

Abstract

Soil water content (SWC) is a key factor for successful vegetation restoration in arid and semiarid regions, and vegetation has significant influences on the spatial patterns and temporal dynamics of SWC. The aim of this study was to investigate the temporal stability of SWC under different restored grasslands in an arid hilly area of Central China. SWC was measured in the 0‐ to 300‐cm soil profile in the natural grassland (Stipa capillata) and three typical planted grasslands (Medicago sativa, Agropyron cristatum, and Caragana korshinskii) over two growing seasons (from June to October 2015 and 2016) under natural rainfall conditions. The results showed that the mean SWC in the natural grassland was approximately 30% higher than those in the planted grasslands. The SWC consumption of the planted legume grasslands in the deepest soil layers (below 200 cm) was higher than that of the natural grassland, owing to the deep root system of the legumes. Both natural and planted grasslands had low SWC temporal stability in the top soil layers (0–50 cm), whereas more stable conditions were gradually observed with increasing the soil depth. The mean value of the mean relative differences of SWC in natural grassland (ca. 15%) was lower than that in the planted grasslands (A. cristatum grasslands) and much lower than that in the scrubland, highlighting the stronger temporal stability of SWC in the natural grassland. In conclusion, natural grassland could maintain higher and stable SWC and is recommended to be used for achieving sustainable vegetation restoration in arid and semiarid regions.

Spatio‐temporal variability of multi‐layer soil water at a hillslope scale in the critical zone of the Chinese Loess Plateau

“…In addition, the number of sites showing temporal stability in SWC did not increase with increasing soil depth. This result is partially consistent with that of Huang et al (2018) (0–300 cm) but inconsistent with that of Zhu et al (2020) (0–70 cm).…”

Soil moisture temporal stability and spatio‐temporal variability about a typical subalpine ecosystem in northwestern China

“…Many studies focused on the relationship between temporal patterns of soil moisture and soil depth within a wide variety of ecosystems (Gao & Shao, ; Grant et al, ; He et al, ; Huang et al, ; Lin, ; Liu et al, ). Although we found lower mean r s than those above reported studies, we also found a significant increase in stability with soil depth.…”

Five‐year soil moisture response of typical cultivated grasslands in a semiarid area: Implications for vegetation restoration

“…The utilization of shallow water was particularly prominent in M. sativa grassland. Many studies have shown that leguminous plants consume more water than gramineous plants in arid and semiarid areas (Cui et al, ; Huang et al, ). Other studies have indicated that the roots of the leguminous plants ( Caragana korshinskii and M. sativa ) were deeply distributed and could consume more deep soil water (Huang, Tian, Wu, Liu, & Dang, ; Jia & Shao, ).…”

“…High yield requires more water and the presence of deep roots that absorb deeper soil water; and the different plant species have different transpiration rates (Siltecho et al, ; Wang et al, ; Wang et al, ). Previous studies have suggested that the root system of the leguminous grasslands was deeper, which resulted in a higher consumption of soil water than the consumption of the gramineous grasslands (Huang et al, ). This process could further aggravate the soil water deficit and hinder the sustainability of field grasslands.…”

“…Previous studies have indicated that the different species cultivated in grasslands play an important role in the observed values of the soil hydraulic parameters (Gonzalez‐Sosa et al, ; Mao & Cherkauer, ). Different cultivated grasslands have critical influence on soil water variation (Huang et al, ). In arid regions, grassland sustainability is commonly associated with the soil water availability (Liu, Chen, & Xu, ; Rodriguez‐Iturbe, ).…”