Trade-off between surface runoff and soil erosion during the implementation of ecological restoration programs in semiarid regions: A meta-analysis

Yi-Fan Liu; David Dunkerley; Manuel López-Vicente; Zhi-Hua Shi; Gao-Lin Wu

doi:10.1016/j.scitotenv.2019.136477

Trade-off between surface runoff and soil erosion during the implementation of ecological restoration programs in semiarid regions: A meta-analysis

Sci Total Environ. 2020 Apr 10:712:136477. doi: 10.1016/j.scitotenv.2019.136477. Epub 2020 Jan 7.

Authors

Yi-Fan Liu¹, David Dunkerley², Manuel López-Vicente³, Zhi-Hua Shi⁴, Gao-Lin Wu⁵

Affiliations

¹ State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi 712100, China.
² School of Earth Atmosphere and Environment, Monash University, Melbourne, Victoria 3800, Australia.
³ Department of Pomology, Experimental Station of Aula Dei, EEAD-CSIC, Zaragoza 50059, Spain.
⁴ State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi 712100, China; College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China; CAS Center for Excellence in Quaternary Science and Global Change, Xi'an 710061, China.
⁵ State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi 712100, China; CAS Center for Excellence in Quaternary Science and Global Change, Xi'an 710061, China. Electronic address: wugaolin@nwsuaf.edu.cn.

PMID: 31931199
DOI: 10.1016/j.scitotenv.2019.136477

Abstract

The application of ecological restoration programs, related to water resources protection and soil erosion control, may have some undesirable outcomes. An important example is the effect that vegetation restoration may have in reducing surface water resources. After searching peer-reviewed articles, we selected 38 publications from 16 countries in comparable areas - semiarid conditions (aridity index <0.5), surface coverage >50% and fine soil texture - to evaluate the effectiveness of different types of vegetation (i.e., forestland, scrubland and grassland) in regulating runoff and sediment transport. In particular, we used three indices: the runoff reduction effect, the sediment reduction effect and the ratio between runoff and sediment reduction. These indices were calculated from measured data reported in the original articles. Results showed that scrubland had higher runoff reduction effect (59% in gentle slopes; 65% in steep slopes) than in grassland (39% on gentle slopes; 43% on steep slopes) and forestland (33% on gentle slopes; 51% on steep slopes). For the three types of vegetation, the sediment reduction effect was >70%. Concerning the ratios between runoff and sediment reduction, grassland showed the lowest ratios (56% on gentle slopes; 53% on steep slopes) compared to forestland (63% on gentle slopes; 65% on steep slopes) and scrubland (93% on gentle slopes; 81% on steep slopes). Our results indicate that low values of ratios between runoff and sediment reduction are the most suitable because they indicate an effective soil erosion and sediment delivery reduction but maintaining surface runoff. Overall, our study demonstrates that grassland may be the best choice for optimizing the trade-off between catchment water yield and soil conservation during the implementation of ecological restoration programs in semi-arid regions.

Keywords: Ecosystem sustainability; Land use policy; Meta-analysis; Soil and water conservation; Trade-off.