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Evapotranspiration (ET) partitioning is crucial for understanding the impacts of ecophysiological and physical processes on water balance and plant water use strategy. Black locust ( Robinia pseudoacacia ) is one of the most widely planted species in the semi-arid Loess Plateau, China. The effects of its water use on stand soil water storage (S) and its water use strategy raised much concern due to soil water depletion and its growth degradation. In this study, meteorological factors, soil water content (SWC), ET components and net primary productivity (NPP) were observed in a black locust plantation during a drier (2015) and a wetter (2016) growing season. ET was 160.0 mm in 2015 and 255.0 mm in 2016, which accounted for 104.1% and 68.6% of the precipitation (P), respectively. Soil evaporation (E) accounted for the majority of ET (45.4–69.4% at monthly scale), while transpiration (T) was the smallest component of ET (9.7–28.8%). These results showed that it is E that consumed more soil water rather than T in the black locust plantation. E should be carefully considered and improved in predicting or modeling water budgets (e.g. soil water, ET partitioning and runoff) in the reforested catchments in this area. Additionally, the monthly T/ET decreased with P increasing, suggesting that black locusts could transpire water more effectively to survive under drier conditions with less P. Our study can not only improve the understanding of water budget in the reforested catchment in the semi-arid Loess Plateau but also provide the significant evidences of investigating the plant water use strategy from the point of ET partitioning. [ABSTRACT FROM AUTHOR]

Great efforts have been made to control soil erosion by restoring plant communities in degraded ecosystems world-wide. However, soil erosion has not been substantially reduced mainly because current restoration strategies lead to large areas of mono-specific vegetation, which are inefficient in reducing soil erosion because of their simple canopy and root structure. Therefore, an advanced understanding of how community functional composition affects soil erosion processes, as well as an improved restoration scheme to reduce soil erosion, is urgently needed., We investigated the effect of community functional composition on soil erosion in restored semi-arid grasslands on the Loess Plateau of China. Community functional composition of 16 restored grasslands was quantified by community-weighted mean ( CWM) and functional diversity ( FD) trait values, which were calculated from nine plant functional traits of thirteen locally dominant plant species. Species richness and evenness were also measured. Soil erosion rates were measured using standard erosion plots. The multimodel inference approach was used to estimate the direction and the relative importance of these biodiversity indices in reducing soil erosion., A robust and strong negative effect of functional divergence ( FDiv) on soil erosion was found. The prevalence of particular trait combinations can also decrease soil erosion. The greatest control over soil erosion was exerted when the community mean root diameter was small and the root tensile strength was great., Synthesis and applications: These findings imply that community functional diversity plays an important role in reducing soil erosion in semi-arid restored grasslands. This means that current restoration strategies can be greatly improved by incorporating community functional diversity into restoration design. We propose a trait-based restoration framework for reducing soil erosion, termed ' SSM' (Screening-Simulating-Maintaining). SSM aims to translate the target of community functional diversity into community assemblages that can be manipulated by practitioners. Based on this framework, a comprehensive procedure, highlighting functional diversity as the primary concern in determining optimal community assemblages, was developed to meet the pressing need for more effective restoration strategies to reduce soil erosion. [ABSTRACT FROM AUTHOR]

Ecological restorations over time may have profound effects on ecological and socio-economic systems. However, land-use changes and landscape functions that accompany ecological restorations can have spatial differentiations due to varied biophysical and socio-economic contexts. Therefore, these spatial differentiations caused by ecological restoration must be understood for better planning and management of restoration activities. The Baota District, with 576 villages in the center of the Chinese Loess Plateau, was selected as the study area because of its dramatic transition from cropland to grassland and shrubland from 1990 to 2010. Using the ArcGIS software and a k-means clustering analysis, an approach to identify types of land-use change patterns (TLCPs) at the village level was developed, and four TLCPs were delineated. The analysis indicated a general pattern of cropland decline by 21.6 %, but revealed significant spatial variations between villages in different TLCPs. Vegetation cover and soil retention, which are key proxies for landscape functions, increased by 22.70 and 108 %, respectively, from 2000 to 2010 with significant spatial heterogeneity. The Universal Soil Loss Equation was employed for the assessment of soil retention. The analysis of landscape metrics revealed a major trend of fragmentation and regularity on the county and village scale; however, spatial variations remained. Physical attributes were used to characterize different TLCPs, and notable differences were found. The spatial heterogeneous change in land use and landscape functions on the village scale may be useful for land use and ecological restoration management policy makers. [ABSTRACT FROM AUTHOR]