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1.
Patterns of species richness for vascular plants in China's nature reserves   总被引:2,自引:0,他引:2  
Explaining the heterogeneous distribution of biodiversity across the Earth has long been a challenge to ecologists and biogeographers. Here, we document the patterns of plant species richness for different taxonomic groups in China's nature reserves, and discuss their possible explanations at national and regional scales, using vascular plant richness data coupled with information on climate and topographical variables. We found that water deficit, energy and elevation range (a surrogate of habitat heterogeneity) represent the primary explanations for variation in plant species richness of the nature reserves across China. There are consistent relationships between species richness and climate and habitat heterogeneity for different taxonomic vascular plant groups at the national scale. Habitat heterogeneity is strongly associated with plant richness in all regions, whereas climatic constraints to plant diversity vary regionally. In the regions where energy is abundant or water is scarce, plant richness patterns were determined by water and habitat heterogeneity, whereas in the region with low energy inputs, water interacting with energy, and habitat heterogeneity determined its species richness pattern. Our results also suggest that energy variables alone do not represent the primary predictor of plant richness.  相似文献   

2.
Mexico is considered a megadiverse country containing more than 10% of the world's biodiversity. The distribution of this species richness and endemism is different among the different Mexican states. We examined the species richness patterns of 13 families of vascular plants (including ferns, gymnosperms and angiosperms) in Mexico using political divisions (states) as units of analysis. We analysed the species richness values (absolute richness, endemic richness and restrictive richness) of these plant families using stepwise multiple regression analysis, assessing their relationship with a set of 10 environmental variables (expressed as heterogeneity coefficients). A combined cluster analysis with multidimensional scaling analysis (MDS) and an analysis of similarities were also undertaken to define the spatial–geographical patterns. Additionally, we proposed a methodological strategy to determine which states of Mexico have priorities for conservation. Our results suggested that the three species richness values used were significantly predicted by environmental factors, especially by climatic heterogeneity. Notwithstanding that a linear pattern was recognized, the Mexican states were gathered in four groups, which were confirmed by the MDS and the cluster analysis: (1) the Yucatan Peninsula, (2) arid Mexico, (3) the Mexican Transition Zone and (4) the megadiverse states. We proposed that 12 Mexican states include all the environmental conditions and are candidates for developing conservation programmes: (1) Quintana Roo, Tabasco and Yucatán, (2) Baja California, Chihuahua and Sinaloa, (3) Guerrero, Jalisco and Nuevo León and (4) Chiapas, Oaxaca and Veracruz.  相似文献   

3.
药用植物野生资源的保护正受到学界乃至全社会的广泛关注。本研究通过收集华中地区(包括湖南、湖北和河南三省)的49个国家级自然保护区的科学考察报告、多样性研究报告以及其他相关文献资料, 结合第四次全国中药资源普查数据, 建立了华中地区国家级自然保护区内药用维管植物数据库, 并评估了这些保护区对华中地区药用维管植物的保护成效。研究发现: 华中地区国家级自然保护区内分布有6,071种药用维管植物, 就地保护比例为81.93%; 其中特有、受威胁和常用药用植物物种数分别为1,479种、224种和448种, 三者受保护比例分别为87.98%、78.87%和91.80%。有32.16%的药用维管植物(2,383种, 特有、受威胁和常用药用植物物种数分别为644种、119种和69种)仅分布于1-5个自然保护区中。森林生态系统类型的自然保护区对不同类群药用植物的保护效果均最好。神农架、金童山、莽山、星斗山及湖南舜皇山5个保护区是所有、特有以及受威胁药用植物物种多样性的热点地区, 是华中地区药用植物保护的重要区域。总体上, 华中地区现有国家级自然保护区较好地覆盖了该地区的药用维管植物, 但药用维管植物的就地保护仍不容懈怠。建议加强对该区域保护空缺物种的野外动态监测和保护。  相似文献   

4.
中国部分自然保护区物种多样性与环境因子的关系   总被引:4,自引:2,他引:2  
采用典范对应分析 CCA 对全国73个自然保护区的种子植物多样性的分析表明:在纬度低于25°N的自然保护区中,物种多样性主要受热量因子和水分因子的影响,并具有较高的种子植物科数和属数值;纬度范围介于25°N和30°N之间的自然保护区,其物种多样性主要受海拔的影响,并且种子植物种数较多,同时有较高的种子植物种属比;在更高纬度范围内,地理及地形因子对物种多样性影响显著,并且随着纬度的增高,纬度因子的作用有增强趋势.  相似文献   

5.
Aim To investigate the general pattern of changes in species richness and diversity of vascular plants due to environmental contamination and associated habitat changes imposed by point polluters, and identify the sources of variation in the response of plant communities to industrial pollution. Location Global. Methods We collected species richness and diversity data from 86 studies that were conducted around 60 atmospheric point polluters worldwide and reported in 95 papers (published in 1953–2007). We used meta‐analysis to search for a general effect and to compare between polluter types and plant groups, and linear regression to describe the latitudinal gradient and to quantify relationships between pollution and effect size. Results Although the species richness of vascular plants generally decreased with pollution, the effects were not uniform across the studies. Polluters that cause soil acidification imposed a stronger detrimental effect on plant diversity than industries whose emissions increased soil pH. An overall adverse effect was primarily due to the contribution of non‐ferrous smelters and aluminium plants; the effects of other SO2‐emitting industries were less detrimental, albeit negative, and the effects of chemical plants, fertilizer factories and cement industries did not differ from zero. Longevity of the pollution impact only made a slight contribution to the detected variation, while adverse effects increased with increase in pollution load. Main conclusions This study is the first demonstration of geographical variation in the responses of plant communities to aerial emissions: adverse effects increased from high to low latitudes, and this pattern was explained primarily by increases in both the diversity of original (undisturbed) communities and mean summer temperatures. The latter result suggests that under a future warmer climate the existing pollution loads may become more harmful. Model calculations indicate that a detectable depauperation of plant communities is unlikely if the polluter emits < 1500 t of SO2 annually.  相似文献   

6.
中国不同地理区域鸟兽物种丰富度的相关性   总被引:9,自引:0,他引:9  
生物类群之间物种丰富度的相关性研究是当前物种多样性研究中的热点问题之一,目前,中国尚无相关的研究报道。我们收集了中国三种区域类型:动物地理亚区、行政区和保护区的鸟兽名录,分析了行政区与保护区、动物地理区和经纬度带中鸟兽物种数比值及其相关性。 结果表明:不同区域、动物地理区和经纬度带中鸟兽物种数都显著相关。保护区尺度鸟兽物种 数的相关系数为0.818和动物地理区中的华北区为0.768,其他所有区域和地理区域的鸟兽物 种数的相关系数都高于0.850。因此,鸟兽物种数的相关关系在一定程度上具有预测价值。我们发现不同区域鸟兽物种数比值无显著性差异;但是,不同区域间鸟兽物种数 比值差异显著。该比值在中国呈中间低四周高的分布趋势,其中东北地区最高。我们还利用历史累积调查数据与非历史累积调查数据进行了鸟兽物种数比值及其相关性分析,发现利用累积数据计算的相关性低于非累积数据计算的相关性,但利用累积数据计算的鸟兽物 种数比值高于非累积数据计算的比值。最后,探讨了为什么鸟类与兽类的物种数目会相关。我们根据物种-面积公式,S=CAZ,导出了两个生物类群物种丰富度的相关关 系式。利用全国不同区域数据拟合,得到Z1/Z2=0.913,Z1/Z2接近于1。于是 ,C1/C2可视为近似等于Ram。本研究可推广到其他不同生物类群物种。物种数量的相关关系为快速评估区域的物种多样性提供了一条途径。  相似文献   

7.
自然保护区在生物多样性保护中起着关键作用,然而也面临外来物种入侵等诸多压力。基于72个已调查国家级自然保护区外来入侵植物数据,重点分析生态环境部发布的四批外来入侵物种名单中已有分布的35种外来入侵植物分布格局及其影响因素。研究发现72个国家级自然保护区平均记录有(7.78±0.47)种外来入侵植物,MaxEnt模型预测结果表明98.69%的国家级自然保护区面临外来植物入侵风险。低纬度地区(8.07±0.73)和中纬度地区(9.64±0.56)国家级自然保护区外来入侵植物数量显著高于高纬度地区(4.53±0.88),且不同类型国家级自然保护区外来入侵植物差异不显著。温度和降雨量是影响外来入侵植物在自然保护区分布的关键因素,且影响不同生活型外来入侵植物分布格局的关键因素不同:温度对一年生草本、藤本和灌木的分布解释量极为显著,保护区建立时间、温度、降雨量和海拔共同影响多年生草本植物在国家级自然保护区的分布。研究结果表明国家级自然保护区外来入侵植物调查与监测还存在很大的空白,未来需要进一步加强自然保护区外来入侵植物研究,并提升外来入侵植物的监管能力。  相似文献   

8.
The factors that determine large-scale patterns of species richness are poorly understood. In particular, biologists have not determined the relative roles of taxon-specific characteristics that influence diversification and distribution, and region-specific features that promote and constrain diversity. We show that the numbers of species of vascular plants and of four terrestrial vertebrate taxa (mammals, birds, reptiles and amphibians) vary in parallel across 296 geographic areas covering most of the globe, even after accounting for sample area, climate, topographic heterogeneity and differences between continents. Thus, a common set of regional characteristics and processes appears to shape patterns of species richness in a diverse set of taxa, despite substantial differences in their biological traits.  相似文献   

9.
我国自然保护区管理存在的问题与对策建议   总被引:44,自引:3,他引:41  
自然保护区是我国可持续发展的重要事业之一,近几年来发展迅猛,取得了丰硕成果。但是,自然保护区的建设和管理存在许多困难和问题。本文结合十几年自然保护的基层工作经验,分析问题所在,提出了一些建议,旨在为自然保护区建设和管理提供现实依据。  相似文献   

10.
The Klamath‐Siskiyou forests of northern California and southern Oregon are recognized as an area of globally outstanding biological distinctiveness. When evaluated at a national or global level, this region is often, necessarily, considered to be uniformly diverse. Due to large variation in biotic and abiotic variables throughout this region, however, it is unlikely that biological diversity is uniformly distributed. Furthermore, land management decisions nearly always occur at spatial scales smaller than this entire region. Therefore, we used field data from a random sampling design to map the distribution of local and regional richness of terrestrial molluscs and salamanders within northern California's portion of the Klamath‐Siskiyou region. We also evaluated the protection afforded by reserves established for varying reasons (e.g. for inspiration and recreation for people vs. species conservation) to hotspots of species richness and species representation of these taxa. No existing reserves were created with these taxa in mind, yet it was assumed that reserves established largely around considerations for the northern spotted owl (Strix occidentalis caurina) would afford adequate protection for many lesser‐known species. Species of terrestrial molluscs and salamanders share two general features: (1) they have extremely low vagility, and (2) they are often associated with moist, cool microclimates. Existing reserves disproportionately included areas of hotspots of species richness for both taxa, when hotspots included the richest c. 25% of the area, whereas non‐reserved lands contained greater than expected areas with lower species richness. However, when a more strict definition of hotspot was used (i.e. the richest c.10% of areas), local hotspots for both taxa were not disproportionately found in reserves. Reserves set aside largely for human aesthetics and recreation and those set aside for biodiversity both contributed to the protection of areas with high (greatest 25%) species richness. Existing biodiversity reserves represented 68% of mollusc species and 73% of salamander species, corresponding to the 99th and 93rd percentiles, respectively, of species representation achieved by simulating a random distribution of the same total area of reservation. Cumulatively, however, reserves set aside for inspiration and biodiversity represented 83% of mollusc species and 91% of salamander species. The existing reserves provide conservation value for terrestrial molluscs and salamanders. This reserve network, however, should not be considered optimal for either taxa.  相似文献   

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Hong Qian 《Ecography》2009,32(3):553-560
Determining the effects of regional and contemporary factors on large-scale patterns in species richness has been a fundamental question in modern ecology and biogeography. However, few studies have examined effects of historical and regional factors on species richness at the global scale, and conclusions are often inconsistent or controversial. Here, I use a comprehensive dataset to examine regional effects on species richness of vascular plants and four taxa of terrestrial vertebrates (mammals, birds, reptiles, and amphibians) in the same set of sample units (ecoregions) in seven biogeographic realms across the globe. The same spatial scale and the same set of environmental variables, which are thought to influence large-scale patterns in species richness of vascular plants and terrestrial vertebrates, are used for all the five taxa. Species richness of each taxon is compared across biogeographic realms. Regional effect on species richness has been found for all the five taxa. Of the 90 realm-pair comparisons for the five taxa between observed richness of a region and the richness of the region predicted by the richness–environment relationship derived from the data of another region, 74 (82.2%) showed significant differences between observed and predicted species richness, indicating that a species richness–environment relationship developed for one region cannot accurately predict species richness in other regions of similar environments.  相似文献   

14.
冷仙  曾源  周键  杨飞龄  武瑞东 《生态学报》2023,43(3):1040-1053
定期开展保护成效评估,是制定保护决策与提升保护地管理效果的重要基础。景观动态能够直观地指示保护地成效,但针对区域尺度保护地网络,采用多指标评价体系的景观保护成效研究还相对缺乏。以我国西南地区102个国家级和省级自然保护区为研究对象,从景观生态状况、自然生境格局与连通性以及人类干扰4个方面构建评价指标体系,应用熵权TOPSIS模型的综合分析方法,评估自然保护区在1990—2015年间的景观保护成效,并探讨自然保护区属性与保护成效间的关系。研究发现:(1)从1990—2000年至2010—2015年评估时段,保护成效上升的自然保护区数量约占77.5%,但低于保护成效综合评价指数平均值的自然保护区数量持续增加,表明自然保护区的整体景观成效趋于两极化发展。(2)自然保护区景观保护成效表现出明显的空间差异性,保护成效明显提升的自然保护区主要分布在川藏滇桂四省区,成效下降的自然保护区主要分布在黔、桂及两者交界区域。(3)不同类型与等级的自然保护区之间保护成效存在差异。类型上,整体成效表现为森林生态类较好、内陆湿地类次之、野生动植物类较差,而保护成效改善程度为野生动物类>内陆湿地类>森林...  相似文献   

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通过收集文献确定了中国嵩草属植物的分布信息,并分析了嵩草属植物丰富度与气候要素的关系.结果表明:嵩草属植物丰富度在中国的云南、四川和西藏交界处及青海东南部和喜马拉雅山区较高,在<40° N、85°-105° E、海拔2500 m以上范围、或热量要素较低、降水量及干燥湿润度(或日照时数)中等范围的分布密度和丰富度范围较大;丰富度与7月平均、最高和最低气温及夏季气温呈显著负相关关系(P<0.05),与温暖指数、年生物学温度、极端最高气温、夏季气温以及7月平均、最高和最低气温等值线的对应关系较好.嵩草属植物丰富度与气候要素多元回归模型中,7月最高气温和春季降水量对丰富度影响显著,7月最高气温的影响最大(P<0.05);逐步回归模型中,7月平均、年均最高和极端最高气温的影响较大(P<0.05);主分量回归模型中,极端最高、7月和夏季气温、Thornthwaite干燥度指数和4-10月日照时数、夏秋季和年降水量的影响较大.嵩草属植物丰富度主要受生长季气温、降水量和日照时数以及极端最高气温、年降水量和土壤水分的共同影响.  相似文献   

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物种丰富度的大尺度地理格局及其成因是宏观生态学和生物地理学的中心议题之一。本文利用中国陆栖哺乳动物分布数据, 结合高分辨率的气候、地形、植被等环境信息, 探讨了中国陆栖哺乳动物及主要类群的物种丰富度格局及其影响因素。结果显示, 中国陆栖哺乳动物物种丰富度具有显著的纬度梯度格局, 总体上呈现出由低纬度向高纬度逐渐减少的趋势, 并与宏观地形具有良好的对应关系; 其中, 亚热带、热带西部山区的物种丰富度最高, 而东部平原地区、西北干旱区和青藏高原腹地则是丰富度的低值区。各主要类群的物种丰富度格局既有相似性, 又存在差异。最优线性模型的分析结果显示, 由归一化植被指数(NDVI)、生态系统类型数和气温年较差构成的回归模型对哺乳动物物种丰富度格局的解释率最高, 其中NDVI对模型解释率的贡献最大, 这表明中国陆栖哺乳动物物种丰富度的地理分异受多种环境因素的共同影响, 其中植被生产力起主导作用。各主要类群的最优线性模型显示, 影响物种丰富度格局的主要环境因子因类群而异, 这可能反映了各类群进化历史及生理适应的差异。  相似文献   

19.
We compare species richness of bryophytes and vascular plants in Estonian moist forests and mires. The material was collected from two wetland nature reserves. Bryophyte and vascular plant species were recorded in 338 homogeneous stands of approximately 1 ha in nine forest and two mire types. Regional species pools for bryophytes and vascular plants were significantly correlated. The correlations between the species richnesses of bryophytes and vascular plants per stand were positive in all community types. The relative richnesses (local richness divided by the regional species pool size) were similar for bryophyte species and for vascular plant species. This shows that on larger scales, conservation of the communities rich in species of one taxonomic plant group, maintains also the species richness of the other. The minimum number of stands needed for the maintenance of the regional species pool of typical species for the every community type was calculated using the species richness accumulation curves. Less stands are needed to maintain the bryophyte species pools (300–5300 for bryophytes and 400–35 000 for vascular plants).  相似文献   

20.
基于最受关注濒危物种分布的国家级自然保护区空缺分析   总被引:2,自引:0,他引:2  
闻丞  顾垒  王昊  吕植  胡若成  钟嘉 《生物多样性》2015,23(5):591-504
我们收集整理了中国96个最受关注濒危物种的分布点信息, 利用Maxent分布模型模拟其中分布点信息较为充分的46个物种的潜在分布区, 将其余50个分布信息极少物种的分布点直接标示在地图上。通过分析单个物种分布被国家级自然保护区覆盖的比例, 以及国家级自然保护区覆盖最受濒危物种分布热点地区的比例, 对国家级自然保护区进行了空缺分析。截至2014年底, 仅16个最受关注濒危物种的预测分布区被保护区覆盖超过10%。在分布有最受关注濒危物种的数目可能超过10种的像元(0.8421º)中, 仅有8.27%得到国家级自然保护区保护; 另外, 仅有10.9%的最受关注濒危哺乳动物分布热点地区、1.13%的最受关注濒危鸟类分布热点地区和7.26%的最受关注濒危植物分布热点地区得到国家级自然保护区覆盖。结果显示国家级自然保护区对大部分最受关注濒危物种覆盖不足, 尤其是对其中的所有长距离迁徙鸟类; 国家级自然保护区对最受关注濒危物种分布热点地区覆盖也不足, 尤其是在中国东部和南部地区, 自然保护区在这些地区的布局亟待优化。  相似文献   

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