1930—2010年额济纳三角洲土地利用景观格局变化

干旱区内陆河流域下游的土地利用、景观格局对水资源调配具有重要意义.本文基于1930、1961、1990、2000、2010年土地利用数据,分析黑河流域下游额济纳三角洲土地利用和景观格局的变化.结果表明: 2010年,研究区沙漠化土地面积占总面积的73.4%,其次是草地,占20.8%.1930—2010年,土地利用变化最明显的特征是草地、农田和建设用地增加;各土地类型间转化突出表现为农田和建设用地的转入;土地利用景观破碎度和多样性增加,优势度降低,且具有明显水源依赖性和地域性差异;土地利用变化使景观趋于均匀、多样、破碎.基于其驱动因素及生态环境效应的探讨,针对人-水-生态协调问题,提出“有计划生态移民、限制农田面积、发展集约式精准农业、增加生态用水比例”的建议.

Land use pattern change in Ejin Delta of Northwest China during 1930-2010.

The land use and landscape pattern in the lower reaches of the arid inland river basin is meaningful to water resource allocation. Based on the land use data in 1930, 1961, 1990, 2000, 2010, the purpose of this study was to quantitatively analyze the change of landscape pattern in the Ejin Delta in the lower reaches of the Heihe River Basin, a typical inland river basin in Northwest China. The results showed that the desert area accounted for 73.4% of the total research area in 2010, and the grassland 20.8%. During the past 80 years, the grassland, farmland and construction land increased. The transformation of land use types were characterized by switching to farmland and construction land. The fragmentation and diversity of the landscape increased, while the dominance of the landscape decreased. The landscape pattern obviously lied on the water resource and had regional diversity. Land use changes tended to make the landscape well distributed, diverse and fragmentized. At last, the driving factors and ecological environment effects of land use change were discussed. In a word, to ensure harmonious development between human and eco hydrology, suggestions such as planning ecological resettlement, limiting farmland area, developing precision agriculture and increasing the proportion of ecological water use should be put forward.