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1.
加强森林生物多样性的保护，对保护生物多样性具有十分重要的作用。四川地处我国西南林区的主体部分，森林资源丰厚，森林生态系统复杂，使森林生物在物种、生态系统和跗信息等三个层次上具有丰富度与多样性。为适应我国生物多样性的保护形势及要求，对四川的森林生物多样性保护工作从八个方面探讨其策略。 相似文献
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森林是陆地生态系统中生物多样性最丰富的生态系统。森林生物多样性对于维持陆地生态系统平衡,保证人类生存和社会经济可持续发展起着不可替代的重要作用。对森林生物多样性进行评估、监测和报告是有效保护生物多样性、合理利用其资源、保证其可持续发展的基础和关键。建立一个有效的生物多样性评价指标体系是对生物多样性正确评估的前提和基础,而合适的指标的筛选是构建这一体系的首要工作。本文从文献分析的角度,分析了生物多样性的评价方法,提出了森林生物多样性评价指标的选择原则以及其中需要注意的一些问题,提出了基于林分水平上的生物多样性评价指标的初步构想,为全面构建森林生物多样性评价指标体系奠定理论基础。 相似文献
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四川地处我国西南林区的主体部份,森林资源丰厚,森林生态系统复杂,森林生物在物种、生态系统、遗传信息三个层次上具有丰富度与多样性.为适应我国生物多样性的保护形势及要求,作者在分析森林生物多样性濒危现状及致危原因的基础上,对四川森林生物多样性的保护工作从八个方面探讨其策略. 相似文献
4.
加强森林生物多样性的保护,对保护生物多样性具有十分重要的作用。四川地处我国西南林区的主体部份,森林资源丰厚,森林生态系统复杂,使森林生物在物种、生态系统和遗传信息等三个层次上具有丰富度与多样性。为适应我国生物多样性的保护形势及要求,对四川的森林生物多样性保护工作从八个方面探讨其策略。 相似文献
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保护森林生态系统中的遗传资源森林以其生物多样性和帮助保持的生态功能而成为人类的一笔宝贵财富。森林和林地中蕴藏的丰富物种对全球、国家和地区范围都有着现实和深远的社会意义和经济意义。森林生态系统中的遗传多样性和物种内及物种间的变异均是它们为环境所迫的适应性结果。同时,遗传多样性也是可持续发展和提高森林资源为人类服务的重要基础。 相似文献
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抚育间伐对森林生物多样性影响研究进展 总被引：29，自引：1，他引：28
森林生物多样性在一定程度上是衡量森林质量的重要指标, 丰富的生物多样性同时也是生态系统稳定的基础, 会促进生态系统功能的优化, 而抚育间伐与森林生物多样性存在密切的关系。文中针对国内外森林抚育间伐对植物、动物和微生物多样性影响的研究进行了综述, 同时针对我国森林尤其是人工林质量低的现状, 提出3点建议:(1)把生物多样性作为评价森林质量的一项重要指标; (2)把抚育间伐作为提高生物多样性和森林质量的一项重要措施; (3)对森林抚育对生物多样性的影响进行长期定位研究。 相似文献
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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
10.
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
11.
In this article, we compared the structure, composition, and diversity of trees, shrubs and saplings, seedlings and herbaceous species of community- and government-managed forests in the lowlands of eastern Nepal. Results suggest that among the trees, the community forest was dominated by a single species, Shorea robusta. However, Shorea robusta and Terminalia myriocarpa were codominant in the government forest. Tree density and basal area were higher in the government forest, but shrub/sapling density and basal area were higher in the community forest, suggesting a positive effect of community management on tree regeneration. Overstory species assemblages showed an obvious compositional difference between the forests, but understory species assemblages were less obvious. Plot-level tree and shrub/sapling species richness was higher in the government forest than the community forest. However, seedling-herbaceous species richness was higher in the community forest. The dominance of Shorea robusta trees in the community forest suggests that people involved in managing forests may be more interested in a limited number of economically valuable species while removing less important trees. Such preferential management practices may increase resource heterogeneity within a forest and maintain species diversity in the understory. Thus, community participation in forest management should be encouraged, with guided management techniques and exercises, to achieve maximum forest recovery, provide sustainable ecosystem services, and maintain forest diversity. 相似文献
12.
Ecosystem-based management (e.g. partial cut harvesting) attempts to mimic natural forest dynamics and maintain structural complexity, and this less intense harvesting may minimize the impact on forest floor fauna and help maintain soil system biodiversity. We tested how different experimental harvesting regimes affect the diversity, abundance and composition of Oribatida at the sylviculture et aménagement forestiers écosystémique (SAFE) research forest located in the Abitibi region in NW Québec. Litter and soil were sampled in June 2006 in the mixedwood boreal forest at SAFE where the following treatments were applied and replicated three times: clear cut harvest, 1/3 partial cut harvest, 2/3 partial cut harvest, prescribed burn (after clear cut harvest) and uncut control. Eight years after harvest, partial cuts had more similar species composition to the uncut control within their respective blocks; however, burned habitat showed a shift in species dominance patterns and harboured a relatively distinct composition and species richness compared to treatments. With the exception of samples from clear cuts, species composition of the harvesting treatments was more similar within blocks than among blocks, suggesting that for less intense harvesting practices, spatial scale (i.e. regional factors) could have a greater influence in structuring oribatid assemblages than harvesting regime, but in more severe disturbances such as burn-after-clear cut harvest, habitat is altered enough to affect oribatid biodiversity. 相似文献
13.
Mapping forest dynamics under climate change: A matrix model 总被引：1，自引：0，他引：1
Jingjing Liang Mo ZhouDave L. Verbyla Lianjun ZhangAnna L. Springsteen Thomas Malone 《Forest Ecology and Management》2011,262(12):2250-2262
Global climate change may be affecting forests around the world. However, the impact of climate change on forest population dynamics, especially at the landscape or regional level, has hardly been addressed before. A new methodology was proposed to enable matrix transition models to account for climate impact on forest population dynamics. The first climate-sensitive matrix (CSMatrix) model was developed for the Alaska boreal forest based on observations from over 15 years of forest inventory. The spatially explicit model was used to map climate-induced forest population dynamics across the region. The model predicted that the basal area increment in the region under natural succession would be hindered by global warming, more so for dry upland areas than for moist wetlands. It was suggested that temperature-induced drought stress could more than offset a predicted increase of future precipitation in the region to lower overall forest productivity. At the same time, stand diversity would increase across the region through transient species redistribution. Accounting for climate conditions made the CSMatrix model more accurate than conventional matrix models. 相似文献
14.
Effects of multiple factors on plant diversity of forest fragments in intensive farmland of Northern Portugal 总被引：1，自引：0，他引：1
Angela Lomba Joana Vicente Francisco MoreiraJoão Honrado 《Forest Ecology and Management》2011,262(12):2219-2228
The joint and independent effects of dominant tree species, forest patch spatial attributes, and forest structure and management as drivers of plant species richness and composition in small forest patches scattered within an intensive agricultural landscape were addressed.In a landscape with scattered urban and intensive dairy agricultural areas in north-west Portugal, within which small forest patches (dominated by pines, eucalypts, or both) represent semi-natural habitat islands, 50 small forest patches, with areas ranging between 0.3 and 3 ha, were selected and surveyed for vascular plant diversity, within dairy farming landscape mosaics dominated by annual forage crops. Explanatory variables were composed of three datasets derived either from GIS mapping or field observations: forest type (dominant tree species), forest patch spatial attributes (patch area and shape index), and measures of forest management and structure (diameter at breast height, tree density per hectare, and percentage cover of vegetation strata). Variations in these forest patch attributes were assessed across forest types, and related to measures of plant diversity (total, native, alien, woody, and herbaceous species richness). Redundancy analysis with variance partitioning was applied to evaluate the joint and independent effects of the three sets of variables on species assemblages. The recent shift in canopy dominance from pine to eucalypt observed in the region appears to be related to a (nonsignificant) tendency for the increase of patch area and to the decrease of patch complexity, as well as several changes in forest structure and management, expressed as a trend to denser tree canopies and lower cover of understory plants. Dominant tree species and attributes related to forest structure and management were the most important factors determining plant diversity. The joint effect of the dominant tree species and forest structure and management resulted in lower levels of plant species richness in eucalypt plantations. These were also more prone to invasion by alien species, probably due to decreased biotic resistance from unsaturated native plant assemblages. Our results draw attention to the importance of dominant tree species and management practices for the maintenance of plant diversity levels (species richness and composition) in dairy landscape mosaics, highlighting the importance of the remnants of semi-natural forests as refuges for plant diversity in the landscape context. Nonetheless, forest plant diversity could further be fostered by promoting naturalness of pine stands and the regeneration of native oak woodlands in some forest areas. This would also diversify the range of ecosystem services that could be provided by forest areas in these peri-urban farmlands. 相似文献
15.
Old growth stands of boreonemoral spruce (Picea abies) forests frequently have a shrub layer dominated by hazel (Corylus avellana) – a species which is generally excluded in intensively managed forests due to clearcutting activities. We sampled understory species composition, richness and biomass, as well as environmental variables beneath these two species and also within forest ‘gaps’ in order to determine the effect of overstory species on understory vegetation. Species richness and biomass of herbaceous plants was significantly greater under Corylus compared with plots under Picea and in forest gaps. Indicator species analysis found that many species were significantly associated with Corylus. We found 45% of the total species found under woody plants occurred exclusively under Corylus. Light availability in spring and summer was higher in gaps than under forest cover but no difference was found between plots under Corylus and Picea. Hence, reductions in light availability cannot explain the differences in species composition. However, Ellenberg indicator values showed that more light demanding species were found under Corylus compared to Picea, but most light demanding species were found in gaps. The litter layer under Picea was three times thicker than under Corylus and this may be an important mechanism determining differences in understory composition and richness between the woody species. The presence of Corylus is an important factor enhancing local diversity and small-scale species variation within coniferous stands. Hence, management should maintain areas of Corylus shrubs to maintain understory species diversity in boreal forests. 相似文献
16.
以GIS为平台,充分利用我国森林资源清查资料和定位监测网络体系,扩展监测内容,从森林景观安全格局角度出发,按照层次分析法构建多层次评价指标体系,对三峡库区森林景观安全格局进行了定量评价,分析了森林景观破碎化程度、多样性、完整性和稳定性对区域森林景观安全格局的影响,其主要目标是评价具有不确定性的灾害或事件对森林生态系统及其组分可能造成的损伤,根据景观安全综合评价值结果,兴山县居库区各县之首,综合评价值达11.553,景观安全程度最高,石柱县、武隆县、秭归县评价值也超过了10,巴东、奉节、夷陵相对较高,重庆市区及周边地区只有5.788,其景观安全程度最低。 相似文献
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为了有效地保护野生木本油脂植物资源,制定科学的开发利用对策,于1983~2002年就甘肃省白龙江林区野生木本油脂植物资源状况进行了调查研究,结果表明:该林区野生木本油脂植物共有30科、42属、62种;其中乔木种类最多,占野生木本油脂植物总种数的56.45%;分布于海拔1700~2500 m范围内针阔混交林带的野生木本油脂植物的种类最多,占野生木本油脂植物总种数的79.03%。 相似文献
18.
针对森林物种多样性保育价值评估尚缺乏逻辑推理方法的现状,提出了更为客观合理的Shannon-Wiener指数评估法.此方法通过森林生态系统的Shannon-Wiener多样性指数和林分面积,计算其物种多样性保育价值.基于此方法,利用第六次全国森林资源连续清查数据和来自中国森林生态系统定位研究网络(CFERN)所属生态站的数万个观测数据,对中国森林物种多样性保育价值进行了计算.结果表明,黑龙江和云南两省生物物种保育总价值在全国名列前茅,海南省尽管单价最高,但森林面积较小,其总价值较低.广大西北以及华北地区森林平均单位面积价值和总价值普遍较低.将全国39种林分类型归为如下几类:单价高总量少型、单价高总量大型、单价低总量少型、单价低总量大型和中间类型,针对不同的类群采取不同的保护政策,有利于推动生物多样性保护工作.与目前流行的支付意愿法(WTP)相比,Shannon-Wiener指数评估法的优越性在于:以生态系统的自然属性为基础,每个指标都具有明确的意义,评价结果更接近理论认识,且结果之间可比性强. 相似文献
19.
Based on the investigation data about the species diversity in Daxing'an Mountains, the difference of species diversity indexes
betweenLarix gmelini forest andLarix gmelini-Betula platyphylla forest was analyzed by the Simpson index (D), Shannon-Wiener index (H), Pielou index (J
sw &J
si), Alatalo index (E
a) and Species richness index (S). The result showed that the species diversity index ofLarix gmelini-Betula platyphylla forest was much higher than that ofLarix gmelini forest in this region. AndLarix gmelini-Betula platyphylla forest was beneficial to maintain the species diversity in Daxing'an Mountains region.
Biography: SONG Guan-ling (1969-), female, Master, assistant professor in Zibo College, Zibo 255000, P.R. China.
Responsible editor: Zhu Hong 相似文献
20.
Impacts of resource extraction on forest structure and diversity in Bardia National Park,Nepal 总被引：1，自引：0，他引：1
Repeated biomass harvesting for human livelihood needs can cause significant changes in forest structure, composition and diversity. Such impacts have often been associated with the distance to villages and their size, but the effects of individual villages in relation to their characteristics have been little studied. Focussing on the issues around communities’ impacts on the forest, this research aimed to understand how resource extraction by two Buffer Zone villages in Nepal's Bardia National Park affects forest structure and diversity. Tree density, basal area, diameter at breast height (DBH), species richness, two diversity indices and disturbance indices were recorded in 108 plots in 12 transects, from March till May 2005, within the park along the village boundaries, where resource extraction occurs, and in the core park area which is isolated from human disturbance. Forest subject to resource extraction had a lower density of trees, smaller DBH and lower species richness and diversity. Forest disturbance declined with distance from the villages but the two villages differed widely in their impact on the forest. Resource use was more intensive in Shivapur village and percentage of trees lopped, average lopping intensity and numbers of dung piles were statistically significant. This was mainly due to the lack of access to Buffer Zone community Forest for Shivapur households. Interviews with villagers suggested that there have been changes in species availability compared to 5 years ago. Households also underestimated the impact of their resource extraction, which may prevent them from changing their behaviour to benefit conservation. It is clear that understanding rural communities’ needs, their framing of resource extraction and utilisation, and dependence on forest resources will be very helpful for long term conservation measures. 相似文献