半干旱地区矿区土地利用时空演变与预测

Spatio-temporal evolution and prediction of land use in semi-arid mining areas

半干旱地区矿区的土地利用格局在采矿干扰下发生着巨大变化,以全国八大煤炭生产基地之一的山西省大同矿区为研究对象,分析1985—2015年土地利用类型的时空变化以及影响土地利用变化的驱动因子,构建RF(Random Forest,RF)-FLUS(Future Land Use Simulation,FLUS)模型模拟预测半干旱区矿区未来土地利用变化,结果表明:(1)1985—2015年,矿区的林地、耕地和水域面积减少,草地和建设用地面积增加。(2)林地、草地分布受气候及距离水系和设施点的距离影响较大;耕地分布受气候、高程及距水域、居民点的距离影响较大;水域分布最重要的影响因子是降水;建设用地分布主要受生产能力和距设施点的距离影响较大。(3)FLUS模型和RF-FLUS模型拟合精度均较高,但RF-FLUS模型比FLUS模型精度更高,更接近实际土地格局变化结果。(4)根据RF-FLUS模型对矿区2025年土地利用变化预测表明,矿区内林地、草地和耕地均呈下降趋势,下降速率变化不大;水域保持不变,建设用地与其他类型(裸地和未利用地)保持稳定上升的趋势。本研究为探究矿区土地格局复杂动态演变机制、探索小尺度土地资源优化路径、促进区域生态健康发展提供有利的科学依据。

Land use and land cover change(LUCC)is a critical factor contributing to regional land planning and ecological environmental protection.LUCCs associated with human activities,such as coal mining,have increased the tension in human-environment interactions.This study explored the spatio-temporal LUCC and its driving factors from 1985 to 2015 in the Datong mining area,which is one of the eight major coal production bases in China.Furthermore,the random forests(RF)-future land use simulation(FLUS)model was proposed to explicitly simulate the spatial trajectories of LUCCs for the year 2025.The results showed that(1)forestland,cropland,and watershed areas kept decreasing,while grasslands and construction lands kept increasing from 1985 to 2015.(2)Climate,elevation,and distance were the most influential factors for the distribution of croplands,forestlands,and grasslands,while precipitation was the most important factor for the distribution of watersheds.Coal production capacity and distance from facilities were the most influential factors for the distribution of construction lands.(3)Both the FLUS and RF-FLUS models had a good fitting accuracy,whereas the RF-FLUS models had a satisfactory kappa index and OA index.(4)Land use simulations for the year 2025 based on the RF-FLUS model indicated that croplands,forestlands,and grasslands will decrease,while construction lands will increase.This study provides a scientific reference for understanding the complex and dynamic evolution of LUCC,exploring the possibilities for the way of land resources,and promoting the sustainable development of coal mining areas.