【作者】 王鑫；

【导师】 肖兴媛； 谈明洪；

【作者基本信息】 山东科技大学 ， 测绘工程（专业学位）， 2025， 硕士

【摘要】 土地利用/覆被变化(LUCC)已成为全球研究的热点领域,其中耕地作为一种兼具自然和经济特征的重要土地资源,其动态演变过程与水资源约束的耦合关系在干旱区尤为显著。水资源短缺已成为内陆干旱区流域长期发展的主要障碍。近年来,耕地扩展进一步加剧了干旱地区的土地退化和水资源压力。因此,合理利用有限的水资源和土地资源去满足未来的粮食需求和经济发展已经成为干旱区亟需解决的问题。本研究以天山北坡经济带为典型的干旱区代表,基于1990-2020年的土地利用数据,系统分析了天山北坡经济带以耕地为主的土地利用时空演变规律;基于统计年鉴数据和实地调研的数据,构建SD模型,综合考虑用水情况对耕地变化的驱动作用,估算出计划外用水,将其作为重要依据之一设计了自然发展情景、水约束情景、水充足情景,预测了天山北坡经济带2035年和2050年在不同情景下的耕地面积;最后基于SD模型的模拟结果和选用的驱动因素及限制因素,将SD模型与PLUS模型耦合,模拟了2035年和2050年不同情景下的耕地时空演变,分析了耕地的时空演变规律及其与水资源约束的互馈机制,并提出了水资源约束下的耕地优化策略和差异化情景下的管理建议。主要结论如下:(1)天山北坡经济带的耕地呈现条带状或斑块状分布,集中在天山北麓冲积扇平原及河流沿岸。1990-2020年间,该区域耕地面积净增加11234.9 km~2,增长率达到81.76%。从整体来看,耕地是所有类型中增速最快的土地利用类型,单一动态度达2.73%。耕地扩张主要源于草地和未利用地转化,同时存在向草地等生态用地的逆向转化。(2)基于SD模型综合考虑各部门用水和节水情况,估算出计划外用水。1990-2020年计划外用水量显著增长,30年内增长了80.15亿立方米。根据计划外用水估算的数量设计了自然发展情景、水约束情景和水充足情景,构建SD模型,在三种情景下预测出天山北坡经济带2035年的耕地面积分别为27931.16 km~2、17199.25 km~2和32826.44 km~2,2050年将达到29288.58 km~2、17866.51 km~2和32890.63 km~2。(3)基于PLUS模型对驱动因素的分析,影响耕地扩张的前三大关键因素分别是人口密度、坡度和到河流的距离。天山北坡经济带的耕地扩张呈现出明显的“近居民点、缓坡临水”的空间分布特征。(4)PLUS模型模拟2035和2050年不同情景下的耕地时空演变,重点分析时空特征。自然发展情景下耕地沿绿洲边缘零散扩张;水约束情景下外围耕地逐步向低耗水地类转化;水充足情景下耕地实现了绿洲荒漠过渡带的成片开发。相比2020年,自然发展情景下耕地预计增长11.8%-17.3%;水约束情景下预计22.9%-24.1%的耕地被弃耕;水充足情景下耕地预计增加32.9%-33.5%。基于此,研究分析天山北坡经济带水资源与耕地的耦合关系,提出差异化情景下的管理建议,期望为干旱区资源配置的可持续性提供参考。更多还原

【Abstract】 Land use/cover change(LUCC)has become a global research hotspot.As an important land resource with both natural and economic characteristics,the coupling relationship between the dynamic evolution of cropland and water resources constraint is particularly significant in arid areas.Water shortage has become a major obstacle to the long-term development of inland arid basins.The expansion of cropland has further aggravated land degradation and water stress in arid areas in recent years.Therefore,rational use of limited water resources and land resources to meet the future food demand and economic development has become an urgent problem to be solved in arid areas.Taking the North slope of Tianshan Mountain Economic Belt(NSTM)as a typical arid area,this study systematically analyzed the spatio-temporal evolution of land use,mainly cropland based on the land use data from 1990 to 2020.Based on the statistical yearbook data and field survey data,a system dynamics(SD)model was constructed,which comprehensively considered the driving effect of water use on cropland change,estimated the unplanned water use,designed the natural development scenario,water constraint scenario and water sufficiency scenario,and predicted the cropland area of NSTM in 2035 and 2050 under different scenarios.Finally,the SD model and PLUS model were coupled to simulate the spatial pattern of cropland under different scenarios in 2035 and 2050 based on the simulation results of SD model and selected driving and limiting factors,and the spatial-temporal evolution of cropland and its mutual feeding mechanism with water resources constraints were analyzed.The optimization strategy of cropland under water resource constraint and management suggestions under different scenarios were put forward.The main conclusions are as follows:(1)The cropland presents a banded or patch distribution in NSTM,concentrated in the alluvial fan plain at the north foot of the Tianshan Mountains and along the river.From 1990 to 2020,the area of cropland in this region will increase by 11,234.9 km~2,with a growth rate of 81.76%.Overall,cropland is the fastest growing land use type among all types,with a comprehensive dynamic rate of 2.7%.The expansion of cropland mainly comes from the transformation of grassland and unused land,and there is also a reverse transformation to ecological land.(2)Based on SD model,the unplanned water use is estimated by considering the water use and water saving of each department comprehensively.Unplanned water consumption increased significantly from 1990 to 2020,increasing by 8.15 billion cubic meters in 40 years.Based on the estimated amount of unplanned water use,we designed the natural development scenario,water constraint scenario and water sufficiency scenario,built an SD model,and predicted that the cropland area of NSTM in 2035 would be 27931.16 km~2,17199.25 km~2and 32826.44 km~2,respectively.In 2050,it will reach 29288.58 km~2,17866.51 km~2and 32890.63 km~2.(3)Based on the analysis of the driving factors by the PLUS model,the top three key factors affecting the expansion of cropland are population density,slope and distance to rivers respectively.The expansion of cropland showed a distinct spatial distribution feature of"close to residential areas and gentle slopes facing water"in NSTM.(4)The PLUS model simulates the spatio-temporal evolution of cropland under different scenarios in 2035 and 2050,with a focus on analyzing the spatio-temporal characteristics.Under the natural development scenario,Cropland expands sporadically along the edge of the oasis.Under the water constrained scenario,the peripheral cropland gradually transforms into low-water-consuming land types.Under the sufficient water scenario,Cropland has achieved large-scale development in the transition zone between oasis and desert.Compared with 2020,cropland is expected to increase by 11.8%-17.3%under the natural development scenario.It is estimated that22.9%-24.1%of the cropland will be abandoned under the water-constrained scenario.Cropland is expected to increase by 32.9%-33.5%under the sufficient water scenario.Based on this,the coupling relationship between water resources and cropland is studied and analyzed in NSTM,and management suggestions under differentiated scenarios are proposed,hoping to provide a reference for the sustainability of resource allocation in arid areas.更多还原