以生境保护优先的北京市第二道绿化隔离地区郊野公园选址方法

  目的  在中国快速城镇化背景下，北京市边缘地区的生态环境不断恶化，绿化隔离带成为控制北京市建成区无序扩张、改善城市生态环境的手段，在绿化隔离带范围内建设郊野公园是落实规划的有效途径。郊野公园的核心目标是在生态保育的同时提供少量的游憩活动，因此对于绿化隔离带范围内生境质量高的区域进行保护应作为郊野公园选址的基础原则。  方法  本文在总结国内外学者相关研究的基础上，以北京市第二道绿化隔离地区为例，构建生境保护优先的郊野公园选址框架，利用InVEST评价模型对研究区域的生境质量进行评价，根据生境质量指数将生境划分为低生境、一般生境、中生境、高生境、极重要生境5个等级。以模型评价结果中极重要生境地区作为郊野公园选址的基础原则选取生境保护优先的备选区范围，叠加周边公园资源、已建和拟建郊野公园、土地利用规划、基本农田保护规划、城市道路网可达性和土地利用现状6个外部建设条件和内部开发条件的指标因子选出适宜建设的区域，再根据植被覆盖类型的空间数据划定所选区域内的生境斑块群类型，最终完成研究区域内生境保护优先型郊野公园的选址和分类。  结果  不同类型的生境空间分布呈现一定差异性，根据不同生境划定混交林、灌丛、阔叶林或针叶林、农田、农田与纯林以及滨水6种类型的郊野公园，在通州区碱厂村、昌平区史家桥村、房山区梨村等村镇划定共41处以生境保护优先的郊野公园用地范围。  结论  以生境保护优先的郊野公园选址方法具有明显的空间定量化优势，其评价结果可以为北京市第二道绿化隔离地区的郊野公园选址提供科学依据。 

Site selection methods of country park with priority of habitat protection in the second green isolated area of Beijing

Objective]Under the background of China’s rapid urbanization,the ecological environment in Beijing urban fringe areas is deteriorating.The green belt has become a means to control the disordered expansion of Beijing’s built-up areas and improve the urban ecological environment.The construction of country parks within the green belt is an effective way to implement the plan.The core goal of country parks is to provide a small amount of recreational activities with ecological conservation.It should be the basic principle to protect the area with high habitat quality within the green belts.Method]On the basis of summarizing the relevant research of scholars at home and abroad,taking the second green belt area of Beijing as an example,this paper constructs a framework of country park site selection with priority of habitat protection,and uses the InVEST model to evaluate the habitat quality of research area.According to the habitat quality index,the habitat was divided into five grades:low habitat,general habitat,medium habitat,high habitat and extremely important habitat.Taking the most important habitat areas as the basic principle of country park site selection in the model evaluation results,the scope of priority alternative areas for habitat protection was selected,and the suitable construction area was selected by adding six external construction conditions and internal development conditions,including surrounding park resources,the built and proposed country parks,land use planning,basic farmland planning,road accessibility and current land use,and then according to the vegetation coverage type.Finally,the site selection and classification of country parks with priority of habitat protection were completed.Result]According to different habitats,six types of country parks were defined:mixed forest,farmland,river,broadleaved forest or coniferous forest and shrub.A total of 41 rural parks with priority of habitat protection were demarcated in Jianchang Village of Tongzhou District,Shijiaqiao Village of Changping District,Li Village of Fangshan District and other villages and towns.Conclusion]The evaluation results can provide a scientific basis for the location of country parks in the second green isolation area of Beijing.