多因素耦合下三峡库区土地利用未来情景模拟

Land use driving forces and its future scenario simulation in the Three Gorges Reservoir Area using CLUE-S model

模型模拟和情景变化分析是未来土地利用变化研究的核心内容,本文以2000年三峡库区土地利用现状为基期数据,利用Binary Logistic模型回归分析驱动因子与土地利用间的关系,利用CLUE-S模型对2010年土地利用进行模拟,校验并确定影响库区土地利用驱动因素的主要参数后,基于自然增长、粮食安全、移民建设和生态保护对2020年、2030年库区土地利用情景予以模拟。结果表明:1通过Binary Logistic模型分析和检验,水田、旱地、林地、草地、建设用地和水域的ROC曲线下面积值均大于0.8,表明所选驱动因子对土地利用的解释能力较强,可用来估算土地利用概率分布;2 2010年各地类模拟结果经验证得Kappa系数分别为水田0.9、旱地0.92、林地0.97、草地0.84、建设用地0.85和水域0.77,总体上能满足模拟与预测需求;3多情景模拟显示库区不同土地利用类型在空间上的竞争关系,以及所带来的对库区粮食安全、移民建设、生态保护的影响,包括水田大量转换为旱地("水改旱")、耕地与林草地被建设占用、林草地开垦为耕地、陡坡耕地退为林草地等行为,需要在土地利用优化中平衡各方面的需求;4多因素、多情景模拟能为库区土地利用提供更为清晰的、可供抉择的政策调控思路。

Model simulation and scenarios change analysis are the core contents of the future land use change study. In this paper, land use status data of the Three Gorge Reservoir Area（TGRA） in 1990 were used as base data. The relationship between driving factors and land use was analyzed by using binary logistic stepwise regression analysis, based on which land use in2010 was simulated by CLUE- S model. After the inspection and determination of main parameters impacting driving factors of land use in the TGRA, land use of the TGRA in 2030 was simulated based on four scenarios, including natural growth, food security, emigrant construction and ecological protection. The results were shown as follows：（1） The areas under ROC curves of land use types were both greater than 0.8 under the analysis and inspection of binary logistic model. These land use types include paddy field, dry land, forestland, grassland,construction land and water area. Therefore, it has a strong interpretation ability of driving factors on land use, which can be used in the estimation of land use probability distribution.（2）The Kappa coefficients, verified from the result of land use simulation in 2010, were showed of paddy field 0.9, dry land 0.95, forestland 0.97, grassland 0.84, construction land 0.85 and water area 0.77. So the results of simulation could meet the needs of future simulation and prediction.（3） The results of multi- scenarios simulation show a spatial competition relationship between different land use types, and an influence on food security, emigrant construction and ecological protection in the TGRA, including some land use change such as the large- scale conversion from paddy field to dry land, the occupation of cultivated land, rapid expansion of construction land from forestland and grassland, the reclamation of cultivated land to forestland and grassland, the conversion of forestland and grassland to cultivated land. Therefore, it is necessary to balance the needs of various aspects in land use optimization, so as to achieve the coordination between social economy and ecological environment.