Simulation of Future Vegetation Coverage Prediction under Different Development Scenarios in the Tibetan Plateau

Abstract

This research utilized GeoSOS-FLUS model to simulate and predict the distribution of vegetation coverage grade in the Tibetan Plateau in the year 2035 under two scenarios: natural development scenario based on historical evolution projection, and ecological protection scenario based on limited transformation policy. First of all, future precipitation and maximum temperature are selected as the main driving factors, supplemented by other factors including relative humidity, sunshine hours, population spatial distribution, slope, slope aspect, elevation, distance to railway and distance to highway, etc.. The vegetation coverage grade of the Tibetan Plateau in 2003 is taken as the base period, and that in 2019 is taken as the end period. Then, a GeoSOS-FLUS prediction model is constructed, based on the cost matrix and neighborhood factors and other related parameters obtained from the two scenarios. Finally, the future vegetation coverage grade distribution in 2035 is predicted by using Markov chain.The results indicated that: ( 1 ) From 1998 to 2019, the bare land of the Tibetan Plateau has the tendency of been transformed into low vegetation coverage, medium vegetation coverage or medium-high vegetation coverage, whereas the area of high vegetation coverage is decreasing.( 2 ) Under the natural development scenario, the areas of the bare land, medium-high and high vegetation coverage of the Tibetan Plateau in 2035 will be reduced by about 2 % compared with the actual vegetation coverage in 2019; the areas of low and medium vegetation coverage will be increased by 2.8 % and 10.3 % respectively. Under this scenario, the vegetation coverage evolution of the Tibetan Plateau bears a positive trend, although the trend will be weakened compared to the historical period.( 3 ) Under the ecological protection scenario, compared with the natural development scenario, the areas of bare land and high vegetation coverage will decrease, and the area of low, medium and medium-high vegetation coverage of the Tibetan Plateau in 2035 will increase. Compared with the results predicted under the natural development scenario, under the ecological protection scenario, the improvement of future vegetation coverage of the Tibetan Plateau is very obvious, and the improvement is mainly contributed by the increase of medium vegetation coverage.