Evolution characteristics and simulation prediction of forest and grass landscape fragmentation based on the “Grain for Green” projects on the Loess Plateau, P.R. China

Abstract

Landscape fragmentation is one of the major environmental challenges to sustainable development under the background of global climate change. Grassland and forest land are the largest landscape types, which have contributed the most to ecosystem services on the Loess Plateau. However, there is no precedent for the combined study of the landscape fragmentation of forest and grassland ecosystems. In particular, there is still a lack of clear spatial significance and a quantitative description of fragmentation at the regional scale. Based on the implementation background for the “Grain for Green” Project, we selected the Loess Plateau as the research area and used the coupled future land use simulation (FLUS) model and landscape fragmentation model to explore the temporal and spatial changes in forest and grass landscape fragmentation. The results showed that (1) Woodland, grassland, and cropland are the main landscape types, and the area of cropland initially increased and then decreased, while the area of woodland and grassland exhibited the opposite trend. In particular, the period from 2000 to 2015 was forest and grass restoration stage. (2) The kappa coefficient was 0.85, and the figure of merit coefficient (FOM) was 0.11 for a 1% random sampling when using FLUS model to predict the land use, and the simulation results are also consistent with the objective change in the current social and economic development. (3) The fragmentation of woodland and grassland were dominated by edge type and core type, and the core type had an absolute advantage. It is predicted that the landscape fragmentation will gradually slowdown in 2030 under different intensities of the “Grain for Green” project. The dynamics of landscape fragmentation are conducive to the reasonable planning and objective evaluation of woodland and grassland spatial allocation and quality improvement.