基于水资源承载力的黑河中游生态建设空间格局优化

Grain for the Green Spatial Pattern Optimization in the Middle Reaches of Heihe River Based on Water Carrying Capacity

以黑河中游为研究区,基于系统动力学模型、灰色线性规划模型和Dyna-CLUES模型,在揭示区域水资源承载力的基础上进行景观结构优化,并通过耕地、林地和草地分布概率的博弈,进行退耕还林区、退耕还草区和人工造林区的空间位置识别,得到如下结果。到2020年,在水资源满足生产发展、生活保障和生态优化的情景下,黑河中游水资源可承载人口为144.16万,可承载工业增加值为79.73亿元,可承载耕地、林地和草地面积分别为3027.88, 953.535和3947.115 km^2。以水资源承载能力为基本约束,黑河中游景观最优结构为耕地2742.49 km^2,林地846.456 km^2,草地2184.57 km^2,水域170.671 km^2,建设用地364.509 km^2,未利用地13289.23km^2。生态建设空间分布格局较分散,退耕还林区集中在高台、临泽和甘州绿洲边缘,以期增强绿洲抵御风沙功能;退耕还草区集中在山丹和肃南的海拔较高、坡度较大、水资源和耕作条件均较差的区域,以期减轻区域水资源压力;人工造林区集中在民乐和山丹两县的耕地外围,以地势平坦、水资源条件相对较好的未利用地为主,以期增强区域水源涵养、水土保持和防风固沙等功能。

This paper takes the middle reaches of Heihe River as the study area, where has the most concentrated oasis in Northwest China with fragile ecological environment and huge conflict between water supply and demand.The water carrying capacity was analyzed based on SD model. Then, the land use quantity structure optimization was carried out by grey linear planning model under the constraint of water resource carrying capacity. Next, the probability of cultivated land, forest and grass land was calculated by the space optimization module of DynaCLUES model, and the optimized spatial pattern were identified through probability game. The results show that when the balance between the supply and demand of water resources is achieved in 2020, the research area can support 1.44 million people, 7.973 billion industrial added values, separately the forests, grass land and cultivated land that the research area can support is 953.535 km^2, 3947.115 km^2 and 3027.88 km^2. The best landscape quantity structure include 2742.49 km^2 cultivated land, 846.456 km^2 forest, 2184.57 km^2 grass land, 170.671 km^2 water area, 364.509 km^2 construction land and 13289.23 km^2 unutilized land. The implementation of returning cropland to forests can enhance the ability of oasis areas to resist hazards caused by wind and sand, mainly in Gaotai, Linze and Ganzhou. The locations of returning cropland to grassland focus in Shandan and Sunan with high altitude,steep slope and poor water, which have poor soil condition and is inappropriate for forest. Forest plantation locations focus in the periphery of cropland in Minle and Shandan, and those areas mainly are flat unused land with good water resource conditions, which are of great significance for water and soil conservation, wind prevention and sand fixation.