Simulating Ecological Functions of Vegetation Using a Dynamic Vegetation Model

Abstract

The ecological functions of vegetation play a significant role in improving human well-being. However, previous studies on ecological functions have only used semi-empirical models, which do not include physiological mechanisms and therefore do not accurately estimate the ecological functions of vegetation under scenarios of future climate change. To address this problem, a process-based dynamic vegetation model (LPJ-GUESS) was used to simulate the ecological functions of vegetation under different climate change scenarios in the Loess Plateau (LP), a typical ecologically fragile area in China. The simulated ecological functions were the carbon stock function (CS), soil conservation function (SC), and the water conservation function (WC). The results showed that: (1) Compared with 2001–2020, the proportion of area by shrub and grass vegetation that was predicted to transform into forest accounted for more than 1% of the area in the LP under the SSP119 scenario and 3% of the area in the LP under the SSP585 scenario during 2081–2100, respectively. (2) Compared with 2001–2020, the CS would decrease in the central and south-eastern regions, the SC would decrease in the western regions, and the WC would decrease in the Qilian, Wushaoling, Xinglong and Liupan Mountains during 2081–2100. (3) The relationships and the corresponding regions between the ecological functions of the vegetation and the corresponding regions in the LP would change significantly under climate change from 2001–2020 to 2081–2100.These results indicate that a process-based dynamic vegetation model can capture the changes in the carbon and water fluxes under changes in the climate and CO2 concentration. It can also capture the vegetation succession, changes in ecological functions, and the transformation of functional relationships, which provide information that is conducive to the management and restoration of vegetation on the LP. This study supplies a novel perspective for vegetation management and high-quality development in other ecologically fragile regions worldwide.