提高北京市山区生态公益林质量的对策研究

在对北京市山区生态公益林的现状进行调查和剖析的基础上,针对其主体是人工林,树种组成以油松、侧柏等喜光树种为主,林龄结构以中、幼龄林为主,空间结构以纯林、单层林为主,现有林分密度普遍偏大,权属组成中集体林比重大,立地质量、林分质量、森林功能总体不高等特点,提出建立国家生态公益林制度,把一些重要地段的生态公益林划归国家生态公益林进行直接建设、管理和保护;同时还应把维护和提高地力、调整森林的组成和结构作为提高森林质量的一项长期策略;作为林业基础建设主体的森林培育要为林业的长期发展服务,生态公益林建设中需要解决的主要问题已由过去的数量问题变成了质量问题,促进林木的生长和提高林分的质量已成为北京市山区公益林生产的主要目标,把森林抚育作为在最终实现这些目标的一项重要技术和途径,其中大面积地对生态公益林进行抚育已成为提高现有森林质量的重要途径.另外,尽可能地利用一些过去开垦的山地现在又弃耕的荒地营造一些质量较高的小片林分.

Strategies on Quality Improving of the Non- commercial Forests in Beijing

The NCF in the mountainous area of Beijing were mainly characterized with young and middle aged plantations composed of pure coniferous tree species,the stand density was usually high and the site quality was generally low with limited functions.On the basis of systematic exploration and analyses of the present situation of the NCF in the mountainous area of Beijing,the four strategies were put forward:Establishing the national NCF system,taking the NCF in some important districts in the mountainous areas of Beijing into the national NCF system for unified construction and management.Setting the long-term strategy of improving and maintaining the land productivity,adjusting the forest composition and structure so as to improve the forest quality in Beijing.Taking growth promotion and quality improvement of forests and plantations as the major targets of NCF development in the mountainous areas of Beijing,since the key problem of the NCF production has been transferred from the quantitative aspects to the qualitative aspects,and silviculture,the foundation of forestry construction,should provide the forestry development with long-term service.Forest tending should be taken as an important technique and approach to ensure the accomplishment of above targets,the tending of large area of NCF has resulted in good effect to improve the current forest quality.It would be important to utilize the deserted croplands in mountainous area for plantations with better quality.