黑河中游灌区尺度土地利用变化及其驱动力研究

Water resources is the key connect to the economical development and ecosystem construction, the issues of serious water resources shortage and management crisis have been focus of contradictions between the water, ecology and economical system. The four irrigated areas which belong to two kinds of irrigated areas in the middle reaches of the Heihe River will take for the study area. The following research methods will be employed in this project, that is, the participatory social survey, field investigation, observation and experiment, remote sensing and geographical information system and simulation model. The response process of crop yield to the irrigating water allocation plans will be researched, the variations of structure of grow plants and land use patterns and its economic benefits by reason of varying water allocation plans will be probed. The model of change of land use pattern will be made under the varying water resources allocation scenarios. The form of water resources participatory integrated management will be put forward on the scale of irrigated area and the purpose is to promote the regional sustainable development of water, ecology and social economics. The study contents are following: Study on farmer response behaviors to water management and the farmland pattern changes; Research on the form of water resources participatory integrated management in the typical irrigating areas; Modeling the water-saving irrigation management on the climate change scenarios. Building the integrated water management model aim at improving livelihood, protecting ecosystem, promoting the coordinated development and management of water, land and related resources, in order to maximize the resultant economic and social welfare in an equitable manner.

土地利用变化是导致全球环境变化的主要因素之一，土地利用变化驱动机制是其核心研究内容。水是干旱区绿洲土地利用模式、经济发展和生态环境建设的纽带。以黑河中游两类（冷凉灌区和平原灌区）四个灌区作为研究区域，以参与式社会调查、野外考察、观测试验为基础，结合遥感、GIS技术和模型模拟方法，利用观测调查数据和社会经济统计数据，结合两种遥感数据融合，研究不同灌溉配水方案的作物产量响应过程，探索农户因不同水资源配置方案导致的作物种植和农用地利用格局变化及其经济效应；建立不同水资源配置情景下的土地利用格局变化模型；提出灌区尺度上的参与式水资源优化配置范式；构建不同农作物空间格局与用地竞争驱动力模型，促进区域水、生态和社会经济的和谐可持续发展。具体研究内容包括：农户对不同水资源配置模式的响应行为和土地利用格局变化研究；不同气候变化情景下作物节水灌溉模拟研究；典型灌区农业土地类型空间分布格局及其驱动力研究。

以黑河中游高台和甘州的四个灌区作为典型试验研究区，以参与式社会调查、野外考察、观测试验为基础，结合遥感、GIS技术和模型模拟方法，利用观测调查数据和社会经济统计数据，结合MODIS和TM融合遥感数据，研究了不同灌区作物种植格局和不同灌溉配水方案的作物产量响应过程，数据融合后时间和空间分辨率和精度均有明显提高，作物种植格局遥感识别效果良好。运用决策树模型探索灌区尺度上农户不同水资源配置方案下的作物种植和农业土地利用格局变化及其经济效应，农户种植模式的选择受水资源配置、预期成本和预期收益的影响，作物灌溉次数是水资源约束条件下影响作物选择的最重要因素，当水资源保障充分时，预期收益是作物种类选择的首要因素，当水资源不足时，预期成本为作物种植的首选因素。进行了主要农作物光谱特征的分析，建立了玉米生育期NDVI时间序列谱，初步实现了基于多源遥感数据对农作物长势的估测。建立了不同水资源配置情景下的土地利用格局变化，提出基于灌区尺度上的农作物种植选择模式和参与式水资源优化配置，构建不同农作物空间格局与用地竞争驱动力模型。