共查询到19条相似文献,搜索用时 203 毫秒
1.
2.
森林生物多样性是衡量森林质量的指标之一,物种的多样性是维护生态系统稳定的基础。抚育间伐森林经营工作是一项必不可少的经营措施。通过对不同间伐措施在森林群落多样性方面的影响进行初步研究,得出的结论对森林经营工作有一定的指导意义。 相似文献
3.
森林生物多样性是衡量森林质量的指标之一,物种的多样性是维护生态系统稳定的基础。抚育间伐森林经营工作是一项必不可少的经营措施。通过对不同间伐措施在森林群落多样性方面的影响进行初步研究,得出的结论对森林经营工作有一定的指导意义。 相似文献
4.
5.
6.
7.
林业发展的基础是森林抚育经营管理,抚育经营管理对改善森林质量、增加生物多样性、促进森林可持续发展等方面具有重要意义,也是森工林区的一项长远目标工作。本文对黑龙江省亚布力林业局森林抚育经营技术与措施进行了简单的研究,并结合林业局森林抚育经营现状,就抚育经营方式等科学管理工作,对抚育经营管理工作提出建议。 相似文献
8.
森林抚育间伐问题与对策探析 总被引:1,自引:0,他引:1
指出了在培育森林的过程中,必须重视抚育间伐工作的开展,有效地开展抚育间伐工作在增加林业生产、提高经济效益的同时,也能够促进育林的效果。但是在现阶段的森林培育工作中,抚育间伐仍然存在着很多的问题,不利于我国森林培育的质量。基于此背景,结合实际工作,介绍了森林抚育间伐的重要作用,阐述了当前森林抚育间伐存在的问题,总结了相应改善建议,以期为我国的森林抚育间伐工作有所启示。 相似文献
9.
林下植物多样性影响因素研究进展 总被引:7,自引:0,他引:7
生物多样性是衡量森林质量的重要指标,生物多样化是生态系统稳定的基础.综述了影响林下植物多样性的因素,指出:1)混交林的生物多样性优于纯林;2)老龄林群落具有较为丰富的物种和复杂的垂直层次结构;3)林分密度越小,越有利于林下植物的多样化;4)适度的间伐强度可显著提高林分的生物多样性. 相似文献
10.
11.
12.
三峡库区森林生态系统物种多样性定量分析 总被引:1,自引:0,他引:1
对三峡库区生物多样性进行定量描述既是现状评价的基础,也是影响预测的基础,更是当前森林经营者将生物多样性纳入规划和决策过程中急需解决的问题。本文根据三峡库区监测样地生物多样性物种调查数据,结合资源调查小班因子与地形环境等因子,分别构建基于区域尺度的三峡库区物种丰度指数、物种多样性指数以及均匀度指数等物种多样性定量指标体系及评价模型,直观地反映三峡库区宏观尺度上的物种的丰度、变化程度或均匀度,揭示森林生态系统的组成与结构的基本差异,较为客观地反映了群落的真实情况,从而为森林生态系统的健康管理提供了量化依据。 相似文献
13.
14.
在分析Patrick、Simpson、Shannon-Wiener及Pielou均匀度等生物多样性评价指数的基础上,提出了区系次生度(F)和生态次生度(E)等指标,定义区系次生度(F)是生态系统中已进入的外来种及已丧失的原生种的种类的百分比,它只与这些物种的种类变化有关而与它们的植株数量变化无关,即F={[a/(b1+a)+b2/(b1+b2)]÷2}×100%;定义生态次生度(E)由系统中外来种的重要值与系统中现存每个种的重要值之和的比值,以及由系统中已经丧失的原生种的重要值与系统中曾经拥有的原生种的重要值之和的比值构成,即E={[i∑=s 1 Ai/(i∑m=1 B1i+i∑=s 1 Ai)+i∑=n 1 B2i/(i∑m=1 B1i+i∑=n 1 B2i)]÷2}×100%。通过在滇西北研究的实例分析,说明引入区系次生度和生态次生度等新指数的合理性和必要性。采用系统中外来入侵种的种类和数量及原生种的种类和数量的变化,用较为直观和易于获得的指标评价系统的生物多样性质量,为生物多样性评价、保护和管理提供更多的依据。 相似文献
15.
ZHANG YingCollege of Economics Management Beiiine Forestry University Beiiine . P. R. China 《中国林业科技(英文版)》2003,(2)
By reference of the evaluative data of forest biodiversity changes in China from 1973 to 1998, the variation analysis models of the pressure index of forest biodiversity, forest ecosystem diversity and forest species diversity, as well as the general index of forest biodiversity are developed using Statistical Package for the Social Sciences (SPSS). Furthermore established is the relevant model of mutation of forest diversity potential functions. This paper points out that changes of forest biodiversity are generally unsteady, especially for the pressure index . The ecosystem diversity index and the species diversity index always fluctuate, resulting in the erratic changes or mutations of general index of forest biodiversity in China. 相似文献
16.
《中国林业科技(英文版)》2010,(2):32-39
The shortage of forest tending funds in China has caused the retarded thinning for those forests that need urgently the tending thinning, which in turn has a negative impact on the implementation of forest management activities and results in the poor state of forest quality, function and healthy. This paper analyzed the necessity to implement forest tending subsidies, concluded the experience abroad, and proposed some policy recommendations on how to implement forest tending subsidies in China. It was indi... 相似文献
17.
In future decades, initiatives on biomass-based energy development in Europe should reduce fossil fuel dependence and help to combat climate change as required by the conference of the parties 21. In this context, forest biomass can play a key role within the bioenergy sector due to its high growth potential. The use of forest biomass for energy has positive and negative effects on other ecosystem services, on stand characteristics, and on forest management practices. The aim of this study is to analyse the effects of forest bioenergy production on six ecosystem services (biodiversity, recreation, landscape aesthetics, carbon sequestration, soil erosion protection, water quality). These effects have been assessed by 80 experts in two countries (Italy and Turkey), considering two different forest management practices (clear-cutting of coppices and woody residue removal after felling in high forests). The results show that coppice clear-cutting has negative effects on almost all ecosystem services according to the experts’ opinions. The highest negative effects are on landscape aesthetics and soil protection. The effects of woody residue removal on biodiversity, carbon sequestration, soil erosion protection, and water quality are considered negative by the experts, while the effects on recreation activities and landscape aesthetics are considered positive. The highest negative effects of this forest management scenario are on soil protection and biodiversity. The experts’ opinions about the effects of forest management practices on ecosystem services can provide information to understand the environmental sustainability of bioenergy development in future years. 相似文献
18.
不同尺度生物多样性监测研究进展 总被引:1,自引:0,他引:1
生物多样性是人类赖以生存和发展的物质基础和环境保障, 构建合理有效的生物多样性监测指标体系是实现科学保护生物多样性的基础。文中从全球、地区/国家、生态系统3个尺度对国际上生物多样性监测指标体系研究的最新进展进行了回顾, 评述各尺度生物多样性保护监测指标体系的优缺点, 提出了在生态系统尺度上建立森林生物多样性保护监测指标体系的必要性。 相似文献