基于坡位单元边界动态调整的流域管理措施情景优化方法

Scenario analysis of best management practices (or beneficial management practices; BMP) based on watershed process simulation can use watershed process model to quantitatively assess the benefit of various BMP scenarios from multiple aspects such as protection of ecology and environment, and economic cost. Combined with multi-objective optimization algorithm, this approach can design those BMP scenarios with maximized comprehensive benefit. These advantages make this approach being an important way to watershed management decision support and the reduction of soil erosion and agricultural non-point source pollution. However, the spatial configuration units (such as field and hydrologic response unit) used in current approaches to optimizing BMP scenarios are with fixed boundary during the optimization procedure. This situation means that in current approaches the BMP configuration cannot be optimized by adjusting the boundary (and then area) of spatial units. Furthermore, the spatial configuration units with fixed boundary show a weak relationship with terrain positions in reality and thus cannot be used reasonably to either depict the slope surface processes or reflect the comprehensive watershed treatment schema in China. To deal with this situation, this proposal suggests the slope positions as the spatial units of BMP configuration, which should be applied to a framework of BMP scenarios optimization based on spatially-distributed watershed model. A dynamic adjustment method of slope position boundary will be designed based on fuzzy slope position information. Correspondingly, an algorithm of optimizing BMP scenarios based on these units with adaptive unit-boundary will be designed to support the search and evaluation of all potential BMP scenarios which accord with the comprehensive watershed treatment schema. By this way, the BMP scenarios optimization will be more reasonably and effectively. This research can prompt the wide-spread application of the comprehensive watershed treatment schema.

基于流域过程模拟的最佳管理措施（BMP）情景分析及优化方法，是通过流域过程模型对各种BMP空间配置方案（称BMP情景）预先定量评估其生态环境和经济等多方面效益，结合多目标优化算法可设计出综合效益最大化的BMP情景，已成为流域管理决策支持、控制水土流失和非点源污染的重要手段。但现有方法采用的地块、水文响应单元等空间配置单元在优化过程中边界固定不变，不能从空间配置单元边界调整的角度优化BMP配置，且与地形部位关系较弱，难以合理体现坡面上自然过程的上下游关系以及我国流域综合治理经验模式。对此，本项目拟在空间全分布式流域模拟的BMP情景优化方法框架下，以坡位为BMP空间配置单元，设计一套利用模糊坡位信息的坡位单元边界动态调整方法以及相应的BMP情景自动优化算法，以搜索、评价符合流域综合治理模式的各种潜在BMP情景，更合理、有效地进行BMP情景优化。该方法可促进流域综合治理模式的推广应用。

本项目的研究目标为：在基于流域过程模拟的流域管理措施（BMP）情景优化方法框架下，以坡位单元作为BMP配置单元，建立一套坡位单元边界动态调整方法以及相应的BMP情景自动优化算法，从而解决现有的BMP空间配置单元边界固化的问题，以更合理、有效地搜索、评价符合流域综合治理模式的各种潜在BMP情景，进行BMP情景优化，促进流域综合治理经验模式的推广应用，科学、实用地为实际流域管理提供决策支持。.针对上述研究目标，本项目开展的研究内容和取得的进展可概括为如下四个方面：1）在坡位单元边界动态调整方法研究方面，建立了一整套基于模糊坡位信息的坡位单元边界动态调整方法以及相应的流域BMP情景自动优化算法，并对新建方法的有效性进行评价。2）对新建方法相关的BMP空间配置单元类型问题开展一系列研究，包括定量分析了不同空间配置单元对BMP情景优化的影响；提出以“坡位-地块”作为流域BMP空间配置单元的可行性等。3）在新建方法所依托的流域系统综合模拟框架的性能问题方面开展研究，迭代完善了新建方法所需的流域建模框架，并提出了数据域分解的负载均衡策略以提高栅格地理计算的并行计算效率，以从建模灵活性和计算效率方面支撑新建方法的实际应用。4）在流域过程模拟所需的精细地理参数制备方法，提出了环境变量重要性权重空间自适应的大区域土壤属性推测方法，以从地理参数精细程度方面支撑本项目新建方法的实际应用。.本项目所取得的方法研究成果在项目执行期中已发表文章8篇，包括7篇期刊论文（其中5篇SCI检索文章）和1篇约稿的英文专著章节，第一资助文章4篇、第二资助文章3篇、第三资助文章1篇，文章发表在相关领域的代表性期刊上（如《Progress in Physical Geography: Earth and Environment》、《International Journal of Applied Earth Observation and Geoinformation》、《International Journal of Geographical Information Science》）。此外，还有两篇文章正投稿本领域主流国际期刊在审中。