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1.
Human population in the biodiversity hotspots   总被引:30,自引:0,他引:30  
Cincotta RP  Wisnewski J  Engelman R 《Nature》2000,404(6781):990-992
Biologists have identified 25 areas, called biodiversity hotspots, that are especially rich in endemic species and particularly threatened by human activities. The human population dynamics of these areas, however, are not well quantified. Here we report estimates of key demographic variables for each hotspot, and for three extensive tropical forest areas that are less immediately threatened. We estimate that in 1995 more than 1.1 billion people, nearly 20% of world population, were living within the hotspots, an area covering about 12% of Earth's terrestrial surface. We estimate that the population growth rate in the hotspots (1995-2000) is 1.8% yr(-1), substantially higher than the population growth rate of the world as a whole (1.3% yr(-1)) and above that of the developing countries (1.6% yr(-1)). These results suggest that substantial human-induced environmental changes are likely to continue in the hotspots and that demographic change remains an important factor in global biodiversity conservation. The results also underline the potential conservation significance of the continuing worldwide declines in human fertility and of policies and programs that influence human migration.  相似文献   

2.
首先涉及到印度、泰国和越南3国陆生生物多样性主要栖息地──森林及自然保护区的概况,然后对3国的物种多样性以及生物多样性的就地保护,迁地保护及持续利用的情况作了介绍,并与我国的情况作些比较。  相似文献   

3.
GAP分析与区域生物多样性保护   总被引:7,自引:0,他引:7  
人为活动对区域生境干扰导致濒危物种数量不断增加,是目前全世界范围内生物多样性保护工作面临的严峻挑战。为扭转传统保护思路难以适应现代生物多样性保护需求这一被动现状,人们开始采用一种基于景观和区域尺度的整体保护策略,GAP分析就是实现这种保护策略的主要支撑技术。该技术的核心是通过区域性的土地覆盖、物种分布和土地权属叠图综合分析,鉴别具有重要保护价值的“保护空白”,进而为合理的区域性生物多样性保护设计和土地利用规划,提供科学的决策依据。以美国的GAP分析计划为例,详细介绍GAP分析的基本技术过程,相关理论和实践研究进展及相关技术应用的主要限制因素,并针对我国生物多样性保护工作的现状和存在的关键问题,阐述了我国开展类似理论和应用研究的必要性、重点研究内容及其理论和实践意义。  相似文献   

4.
International trade drives biodiversity threats in developing nations   总被引:1,自引:0,他引:1  
Lenzen M  Moran D  Kanemoto K  Foran B  Lobefaro L  Geschke A 《Nature》2012,486(7401):109-112
Human activities are causing Earth's sixth major extinction event-an accelerating decline of the world's stocks of biological diversity at rates 100 to 1,000 times pre-human levels. Historically, low-impact intrusion into species habitats arose from local demands for food, fuel and living space. However, in today's increasingly globalized economy, international trade chains accelerate habitat degradation far removed from the place of consumption. Although adverse effects of economic prosperity and economic inequality have been confirmed, the importance of international trade as a driver of threats to species is poorly understood. Here we show that a significant number of species are threatened as a result of international trade along complex routes, and that, in particular, consumers in developed countries cause threats to species through their demand of commodities that are ultimately produced in developing countries. We linked 25,000 Animalia species threat records from the International Union for Conservation of Nature Red List to more than 15,000 commodities produced in 187 countries and evaluated more than 5?billion supply chains in terms of their biodiversity impacts. Excluding invasive species, we found that 30% of global species threats are due to international trade. In many developed countries, the consumption of imported coffee, tea, sugar, textiles, fish and other manufactured items causes a biodiversity footprint that is larger abroad than at home. Our results emphasize the importance of examining biodiversity loss as a global systemic phenomenon, instead of looking at the degrading or polluting producers in isolation. We anticipate that our findings will facilitate better regulation, sustainable supply-chain certification and consumer product labelling.  相似文献   

5.
长江中下游四省森林植物多样性初步分析   总被引:3,自引:0,他引:3  
分析了长江中下游湘、赣、鄂、皖四省的森林植物多样性现状和潜在危机。统计结果表明,该区植物(包括种子植物、蕨类植物和苔藓植物)物种多样性水平估计为1万种,具古老性、特有性、稀有性和复杂性等特点。该区生物多样性现状是不容乐观的,物种、基因和生态系统诸层次的多样性均受不同程度的破坏,它对经济持续发展、环境保护等方面有潜在的负面影响。提出了该区生物多样性保护的若干对策。  相似文献   

6.
作者根据多年收集到的资料,分析了安徽大别山区经济动物的种数、利用状况和它们在我国生物多样性保护中的意义,为从宏观和微观上进一步研究我国森林生态系统优生保护区之一的大别山区生物多样性打下基础。  相似文献   

7.
Many natural habitats exist on privately owned land outside protected areas, but few governments can afford to enforce or subsidize conservation of this biodiversity. Even in some developed countries, conservation subsidy schemes have only achieved limited success. Fortunately, some landowners may be willing to accept management costs in return for other benefits, although this remains controversial when it involves the killing of charismatic species. For example, participants in British field sports, such as fox hunting and game-bird shooting, may voluntarily conserve important habitats that are required by quarry species. Here we report results from a multidisciplinary study that addressed this issue by focusing on three sites across central England. We found that landowners participating in field sports maintained the most established woodland and planted more new woodland and hedgerows than those who did not, despite the equal availability of subsidies. Therefore, voluntary habitat management appears to be important for biodiversity conservation in Britain. Current debates on the future of field sports in Britain, and similar activities globally, may benefit from considering their utility as incentives to conserve additional habitat on private land.  相似文献   

8.
简述了祁连山自然保护区森林生物多样性特征,森林病虫鼠害发生与生物多样性的关系,说明导致森林病虫鼠害大发生的森林生物多样性原因在于:森林树种、森林类型及其分布状况比较单纯;林分结构多样性简单;灌草植被种类虽多,超群种类较少;人为干扰破坏严重,生物多样性趋于减少;天敌种群数量低,不能有效控制森林有害生物种群上升.提出了生物多样性保护与森林有害生物可持续治理的策略与措施.  相似文献   

9.
Ives AR  Cardinale BJ 《Nature》2004,429(6988):174-177
Growing concern about how loss of biodiversity will affect ecosystems has stimulated numerous studies. Although most studies have assumed that species go extinct randomly, species often go extinct in order of their sensitivity to a stress that intensifies through time (such as climate change). Here we show that the consequences of random and ordered extinctions differ. Both depend on food-web interactions that create compensation; that is, the increase of some species when their competitors and/or predators decrease in density due to environmental stress. Compensation makes communities as a whole more resistant to stress by reducing changes in combined species densities. As extinctions progress, the potential for compensation is depleted, and communities become progressively less resistant. For ordered extinctions, however, this depletion is offset and communities retain their resistance, because the surviving species have greater average resistance to the stress. Despite extinctions being ordered, changes in the food web with successive extinctions make it difficult to predict which species will show compensation in the future. This unpredictability argues for 'whole-ecosystem' approaches to biodiversity conservation, as seemingly insignificant species may become important after other species go extinct.  相似文献   

10.
以巴尔鲁克山自然保护区的森林生态系统为研究对象,从物质量与价值量的角度,采用影子工程法、机会成本法、市场价值法等研究方法,对巴尔鲁克山自然保护区森林生态系统生产有机物、涵养水源、保育土壤、固碳释氧、净化环境、营养元素积累、生物多样性保护、森林游憩这8项功能12个指标进行价值量评估,最后算出研究区森林生态系统服务功能总价值和单位面值价值。结果表明:该自然保护区森林生态系统服务功能总价值为:7.05×108元·a-1,单位面积价值为:3.08×104元·hm-2·a-1。其中,直接经济价值为0.5×104元·a-1,占总价值中的7.04%;间接价值总和为6.6×104元·a-1,占总价的92.96%。各项功能价值的大小顺序为:固碳释氧价值涵养水源价值生物多样性保护价值保育土壤价值游憩价值积累有机物价值净化环境价值生产有机物价值。  相似文献   

11.
Effects of household dynamics on resource consumption and biodiversity   总被引:41,自引:0,他引:41  
Liu J  Daily GC  Ehrlich PR  Luck GW 《Nature》2003,421(6922):530-533
Human population size and growth rate are often considered important drivers of biodiversity loss, whereas household dynamics are usually neglected. Aggregate demographic statistics may mask substantial changes in the size and number of households, and their effects on biodiversity. Household dynamics influence per capita consumption and thus biodiversity through, for example, consumption of wood for fuel, habitat alteration for home building and associated activities, and greenhouse gas emissions. Here we report that growth in household numbers globally, and particularly in countries with biodiversity hotspots (areas rich in endemic species and threatened by human activities), was more rapid than aggregate population growth between 1985 and 2000. Even when population size declined, the number of households increased substantially. Had the average household size (that is, the number of occupants) remained static, there would have been 155 million fewer households in hotspot countries in 2000. Reduction in average household size alone will add a projected 233 million additional households to hotspot countries during the period 2000-15. Rapid increase in household numbers, often manifested as urban sprawl, and resultant higher per capita resource consumption in smaller households pose serious challenges to biodiversity conservation.  相似文献   

12.
Primary forests are irreplaceable for sustaining tropical biodiversity   总被引:6,自引:0,他引:6  
Human-driven land-use changes increasingly threaten biodiversity, particularly in tropical forests where both species diversity and human pressures on natural environments are high. The rapid conversion of tropical forests for agriculture, timber production and other uses has generated vast, human-dominated landscapes with potentially dire consequences for tropical biodiversity. Today, few truly undisturbed tropical forests exist, whereas those degraded by repeated logging and fires, as well as secondary and plantation forests, are rapidly expanding. Here we provide a global assessment of the impact of disturbance and land conversion on biodiversity in tropical forests using a meta-analysis of 138 studies. We analysed 2,220 pairwise comparisons of biodiversity values in primary forests (with little or no human disturbance) and disturbed forests. We found that biodiversity values were substantially lower in degraded forests, but that this varied considerably by geographic region, taxonomic group, ecological metric and disturbance type. Even after partly accounting for confounding colonization and succession effects due to the composition of surrounding habitats, isolation and time since disturbance, we find that most forms of forest degradation have an overwhelmingly detrimental effect on tropical biodiversity. Our results clearly indicate that when it comes to maintaining tropical biodiversity, there is no substitute for primary forests.  相似文献   

13.
【目的】评估江苏省重点公益林的生态服务功能及价值。【方法 】依据《森林生态系统服务功能评估规范》(LY/T 1721— 2008),利用江苏省森林资源二类调查资料,以及长江三角洲森林生态系统定位研究站长期监测数据和相关研究成果,对江苏省重点公益林生态服务功能及价值进行评估。【结果】江苏省重点公益林生态服务功能总价值为400.63亿元/a,是每年投入的257倍。各项生态服务功能价值大小次序为:涵养水源价值>固碳释氧价值>生物多样性保护价值>森林游憩价值>积累营养物质价值>净化大气环境价值>森林防护价值>保育土壤价值。针叶类树种以及梨、柿、板栗、杜仲、油桐等经济树种生态服务功能较高,其他硬阔及杨树面积大,但其单位面积生态服务功能价值均较低。【结论】公益林分布区应适当将杨树、其他硬阔树种等更新为针叶类,或者梨、柿、板栗、杜仲、油桐等经济树种,以提高江苏省重点公益林的生态服务功能价值。  相似文献   

14.
贵阳环城喀斯特人工林生态系统服务功能评价   总被引:1,自引:0,他引:1  
以贵阳市环城喀斯特人工林为研究对象,探讨森林生态系统服务功能的内涵,使用市场价值、替代花费等方法定量评估贵阳市环城喀斯特人工林生态系统服务功能的经济价值。结果表明,面积为8.8万ha.的环城人工林生态系统服务功能价值平均每年46,803.56万元。其中林产品价值为8894.68万元、涵养水源价值为9232.48万元、土壤保持减少侵蚀价值为4,105.24万元、固定CO2减轻温室效应的价值为4,484.74万元、净化空气的价值为15,592.63万元、释放O2的价值为339.17万元、科学研究价值为1,846.5万元、生物多样性价值为2,308.12万元。  相似文献   

15.
腐败是全球普遍存在的社会毒瘤,对腐败的研究成为社会科学研究的热点,如何消除腐败,建立廉洁高效的政府是各国面对的难题,解决这一问题,需要对腐败的成因做详尽的探究,才能对症下药。对各类探讨腐败行为成因的文献进行了梳理,从政治学、经济学、心理学等研究视角综述了腐败行为产生的大致原因,并在此基础上分析了其对于当前反腐工作的几点启示,并特别指出,需重视行政官员的心理健康教育和腐败成因的数据模型建构。  相似文献   

16.
Global conservation strategies commonly assume that different taxonomic groups show congruent geographical patterns of diversity, and that the distribution of extinction-prone species in one group can therefore act as a surrogate for vulnerable species in other groups when conservation decisions are being made. The validity of these assumptions remains unclear, however, because previous tests have been limited in both geographical and taxonomic extent. Here we use a database on the global distribution of 19,349 living bird, mammal and amphibian species to show that, although the distribution of overall species richness is very similar among these groups, congruence in the distribution of rare and threatened species is markedly lower. Congruence is especially low among the very rarest species. Cross-taxon congruence is also highly scale dependent, being particularly low at the finer spatial resolutions relevant to real protected areas. 'Hotspots' of rarity and threat are therefore largely non-overlapping across groups, as are areas chosen to maximize species complementarity. Overall, our results indicate that 'silver-bullet' conservation strategies alone will not deliver efficient conservation solutions. Instead, priority areas for biodiversity conservation must be based on high-resolution data from multiple taxa.  相似文献   

17.
生态遗传学是种群生态学和种群遗传学相互渗透、相互结合的综合性学科,是天然林遗传资源保护的理论基础.应用生态遗传学研究天然林生态系统中遗传和演替的关系、种群和生态系统的相互关系等,有助于更好地进行天然林遗传资源的管理、生物多样性保护以及健康维护,能够科学地指导天然林资源的合理利用、生态恢复和物种引进.  相似文献   

18.
Global tests of biodiversity concordance and the importance of endemism   总被引:1,自引:0,他引:1  
Understanding patterns of biodiversity distribution is essential to conservation strategies, but severe data constraints make surrogate measures necessary. For this reason, many studies have tested the performance of terrestrial vertebrates as surrogates for overall species diversity, but these tests have typically been limited to a single taxon or region. Here we show that global patterns of richness are highly correlated among amphibians, reptiles, birds and mammals, as are endemism patterns. Furthermore, we demonstrate that although the correlation between global richness and endemism is low, aggregate regions selected for high levels of endemism capture significantly more species than expected by chance. Although areas high in endemism have long been targeted for the protection of narrow-ranging species, our findings provide evidence that endemism is also a useful surrogate for the conservation of all terrestrial vertebrates.  相似文献   

19.
Downing AL  Leibold MA 《Nature》2002,416(6883):837-841
Resolving current concerns about the role of biodiversity on ecosystems calls for understanding the separate roles of changes in species numbers and of composition. Recent work shows that primary productivity often, but not always, saturates with species richness within single trophic levels. However, any interpretation of such patterns must consider that variation in biodiversity is necessarily associated with changes in species composition (identity), and that changes in biodiversity often occur across multiple trophic levels. Here we present results from a mesocosm experiment in which we independently manipulated species richness and species composition across multiple trophic levels in pond food webs. In contrast to previous studies that focused on single trophic levels, we found that productivity is either idiosyncratic or increases with respect to species richness, and that richness influences trophic structure. However, the composition of species within richness levels can have equally or more marked effects on ecosystems than average effects of richness per se. Indirect evidence suggests that richness and associated changes in species composition affect ecosystem attributes through indirect effects and trophic interactions among species, features that are highly characteristic of natural, complex ecosystems.  相似文献   

20.
Biodiversity hotspots have a prominent role in conservation biology, but it remains controversial to what extent different types of hotspot are congruent. Previous studies were unable to provide a general answer because they used a single biodiversity index, were geographically restricted, compared areas of unequal size or did not quantitatively compare hotspot types. Here we use a new global database on the breeding distribution of all known extant bird species to test for congruence across three types of hotspot. We demonstrate that hotspots of species richness, threat and endemism do not show the same geographical distribution. Only 2.5% of hotspot areas are common to all three aspects of diversity, with over 80% of hotspots being idiosyncratic. More generally, there is a surprisingly low overall congruence of biodiversity indices, with any one index explaining less than 24% of variation in the other indices. These results suggest that, even within a single taxonomic class, different mechanisms are responsible for the origin and maintenance of different aspects of diversity. Consequently, the different types of hotspots also vary greatly in their utility as conservation tools.  相似文献   

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