Rights statement: This is the author’s version of a work that was accepted for publication in Agriculture, Ecosystems & Environment. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Agriculture, Ecosystems & Environment, 273, 2019 DOI: 10.1016/j.agee.2018.12.008
Accepted author manuscript, 2.84 MB, PDF document
Available under license: CC BY-NC-ND: Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License
Final published version
Research output: Contribution to Journal/Magazine › Journal article › peer-review
| <mark>Journal publication date</mark> | 1/03/2019 |
|---|---|
| <mark>Journal</mark> | Agriculture, Ecosystems and Environment |
| Volume | 273 |
| Number of pages | 11 |
| Pages (from-to) | 25-35 |
| Publication Status | Published |
| Early online date | 13/12/18 |
| <mark>Original language</mark> | English |
Re-vegetation is a necessary control measure of soil erosion in the Loess Plateau. However, excessive re-vegetation can aggravate soil water shortage, which can in turn threaten the health and services of restored ecosystems. An optimal plant cover or biomass (i.e., soil-water carrying capacity for vegetation, SWCCV) is important for regional water balance, soil protection and vegetation sustainability. The objective of this study was to determine the spatial distribution of SWCCV for three non-native tree (Robinia pseudoacaia), shrub (Caragana korshinskii) and grass (Medicago sativa) species used in the re-vegetation of the Loess Plateau. The dynamics of actual evapotranspiration (AET), net primary productivity (NPP) and leaf area index (LAI) were simulated using a modified Biome-BGC (Bio-Geochemical Cycles) model. Soil and physiological parameters required by the model were validated using field-observed AET for the three plant species at six sites in the study area. The validated model was used to simulate the dynamics of AET, NPP and LAI for the three plant species at 243 representative sites in the study area for the period 1961–2014. The results show that spatial distributions of mean AET, NPP and LAI generally increased from northwest to southeast, much the same as mean annual precipitation (MAP) gradient. In terms of maximum LAI, the ranges of optimal plant cover were 1.1–3.5 for R. pseudoacaia, 1.0–2.4 for C. korshinskii and 0.7–3.0 for M. sativa. The corresponding SWCCV, expressed as NPP were 202.4–616.5, 83.7–201.7 and 56.3–253.0 g C m−2 yr−1. MAP, mean annual temperature, soil texture and elevation were the main variables driving SWCCV under the plant species; explaining over 86% of the spatial variations in mean NPP in the study area. Further re-vegetation therefore needs careful reconsideration under the prevailing climatic, soil and topographic conditions. The results of the study provide a re-vegetation threshold to guide future re-vegetation activities and to ensure a sustainable eco-hydrological environment in the Loess Plateau.