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91.
92.
浅析竹类植物的城市生态环境效应 总被引:11,自引:0,他引:11
竹子具有显著的生态效应,在生态建设中发挥着巨大的作用。在总结有关竹类植物生态效应研究成果的基础上,针对现代城市环境特点,着重分析竹类植物对城市环境的生态作用,指出在城市生态环境建设中应重视竹类植物的运用及其生态功能的持续有效发挥。 相似文献
93.
94.
森林与生态环境 总被引:1,自引:1,他引:1
纪仁生 《内蒙古林业调查设计》2000,23(4):1-4
文章运用大量数据和事实 ,详述了森林——这一陆地生态系统的主要构成者 ,在保护陆地生态、改善人类生存环境中的多种功能和作用 ,是不可替代也是无与伦比的。对此 ,人类社会正逐步达成共识。文章还针对我国西部开发及内蒙古生态建设中的森林保护问题提出积极建议 相似文献
95.
96.
浙江省安吉县竹子生态旅游发展思考 总被引:4,自引:0,他引:4
浙江省安吉县是著名的“中国竹乡”,拥有竹林面积6.7万hm^2,乡土竹种7属40余种,旅游资源十分丰富。近年来,随着生态旅游的兴起,安吉县以“竹”为特色,大力发展生态游,改善基础设施和旅游景点设施,使竹子生态旅游业成为安吉县的经济新亮点之一,该文从竹子的旅游观赏和审美价值,竹文化、竹子生态旅游的发展前景、发展建设等方面对安吉的竹子生态旅游业进行初略的探讨。 相似文献
97.
The effects of selection felling and gap felling on arthropod communities were studied over 3 years in a spruce-beech stand in southern Bavaria, Germany. The arthropods were sampled in three strata, using pitfall traps on the forest floor as well as flight-interception traps near the forest floor and in the tree crowns. Coleoptera, Araneae, Opiliones, Heteroptera, Isopoda, Diplopoda and Neuropterida were determined to species level and assigned to ecological guilds. In general, the effects of both treatments on arthropod communities were small. An increase of eurytopic species and species of open woodland as well as of indwellers of deadwood was observed, mainly in the first year after felling. However, forest species dominated the communities in all plots, strata and years. In contrast to selection fellings, gap fellings might favour potential pest species. Nevertheless, in the studied managed spruce-dominated forest site out of the natural growth range of spruce, negative ecological effects such as the repression of forest arthropod species are not expected by small scale fellings. 相似文献
98.
Trade-offs among wood production, wood quality and ecological characteristics in the management of harvested forest stands are explored through model simulation of various silvicultural regimes. Long-term production of merchantable wood, production of various types of high-quality wood, and the level of certain quantitative ecological indicators are projected for coniferous forests of Pacific Northwestern USA. The set of ecological indicators used is based on the species composition and physical structure of old, unlogged forest stands. Simulations are performed with an ecological model of forest stand dynamics that tracks the fate of live and dead trees. Short rotations (<50 years) produce the least amount of high-quality wood over the multi-century simulation period. They also fail to generate ecological attributes resembling those of old forest stands. Production of high-quality wood is moderate to high under all rotations of 80 years or more; however, most ecological indicators require longer rotations unless alternatives to clearcutting are applied. Alternatives examined include retention of 15% cover of live tree canopy at each harvest in combination with artificial thinning between harvests. Thinning from below can expedite the development of large live and dead trees, and canopy height diversity without greatly diminishing wood quantity or quality. Proportional thinning retains understory stems, thereby expediting the recruitment of shade-tolerant trees. A possible drawback to thinning, particularly proportional thinning, is the diminished production of clean-bole wood at rotations of 150 and 260 years. It is concluded that most wood quantity, wood quality and ecological objectives can be met with long rotations (ca. 260 years). Certain objectives can be met with shorter rotations (80–150 years) when treatments of thinning and canopy tree retention are applied. 相似文献
99.
用可持续发展观对建设生态园林城市工作进行分析,探讨我省创建园林城市和生态园林城市的思路和方法。 相似文献
100.
通过对常绿阔叶林研究,努力探索一条发展常绿阔叶林的途径。将阔叶林划分为3个经营类型,分别为:初期幼龄林组成抚育类型、中期幼龄林抚育间伐类型、中龄林密度管理类型。并提出小面积皆伐的采伐方式。同时对常绿阔叶林的生态功能和生产力进行初步研究。 相似文献