基于Markov-PLUS模型的柴北缘土地利用变化及模拟分析

Land Use Change and Simulation Analysis in the Northern Margin of the Qaidam Basin Based on Markov-PLUS Model

以柴达木盆地北缘为研究区域,分析近30 a柴北缘土地利用时空变化,可为区域生态环境保护、土地利用方式优化提出建议。基于1990、2000、2010、2020年4期Landsat影像数据,获取土地利用空间分布数据,借助转移矩阵、重心模型对近30 a柴北缘土地利用时空变化及驱动力计算分析,利用Markov-PLUS复合模型对2040年柴北缘土地利用变化进行预测和模拟。结果表明:1)未利用地、林地、水域是柴北缘的主要用地类型。近30 a耕地面积缓慢增加,重心向西南方向移动,建设用地面积增长迅速,林地、草地、水域面积总体呈上升趋势,重心都向西北方向移动,未利用地面积持续下降。2)使用FLUS模型与Markov-PLUS模型分别预测柴北缘2020年土地利用情况并对比分析,Markov-PLUS模型比FLUS模型的模拟准确性更高。3)2040年多情景模拟结果表明,柴北缘土地利用整体格局一致性较高,城镇发展和耕地保护情景下均会挤占林地、草地,对可持续发展造成威胁,在区域生态安全建设中应加以重视。PLUS模型与Markov模型相结合,实现了对未来土地利用斑块级的精准预测,可为未来提升柴北缘生态退化整治效果、城镇开发边界与生态保护红线的制定与规划等提供科学决策参考。

Taking the northern margin of the Qaidam Basin as the study area,the spatio-temporal changes and transformations of land use in the past 30 years were analyzed.Suggestions for regional eco-environmental protection and land use optimization were put forward.Based on the 4-period Landsat images of 1990,2000,2010 and 2020,the spatial distribution data of the land use were obtained.Using transfer matrix and barycenter model,the spatial and temporal changes of land use were analyzed and the land use pattern in 2040 was simulated by using the Markov-PLUS model.The results showed that 1)unused land,woodland and water area were the main land use types in the region.In the past 30 years,the area of cultivated land increased slowly,the key areas of different land use types moved to the southwest,the area of construction land increased rapidly,the area of woodland,grassland and water area increased generally,and the key area moved to the northwest.The area of unused land continued to decline.2)FLUS model and Markov-PLUS model were used to forecast the land use in 2020 and the results were compared.The simulation precision of Markov-PLUS model was higher than that of FLUS model.3)The results of multi-scenario simulation in 2040 showed that the overall pattern of land use in the region would be highly consistent,and both urban development and cultivated land conservation scenarios would threaten the sustainable development of the region,attention should be paid to the construction of regional ecological security.The combination of PLUS model and the Markov model can realize the accurate prediction of future land use in patch level,it provides scientific decision-making reference for improving the effect of ecological degradation management,planning urban development boundary and ecological protection red line in the future.