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Most attempts to identify important areas for biodiversity have sought to represent valued features from what is known of their current distribution, and have treated all included records as equivalent. We develop the idea that a more direct way of planning for conservation success is to consider the probability of persistence for the valued features. Probabilities also provide a consistent basis for integrating the many pattern and process factors affecting conservation success. To apply the approach, we describe a method for seeking networks of conservation areas that maximize probabilities of persistence across species. With data for European trees, this method requires less than half as many areas as an earlier method to represent all species with a probability of at least 0.95 (where possible). Alternatively, for trials choosing any number of areas between one and 50, the method increases the mean probability among species by more than 10%. This improvement benefits the least-widespread species the most and results in greater connectivity among selected areas. The proposed method can accommodate local differences in viability, vulnerability, threats, costs, or other social and political constraints, and is applicable in principle to any surrogate measure for biodiversity value.  相似文献   

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优先保护区识别对受威胁物种的多样性保护具有重要价值。基于GIS空间分析、管理及预测能力,以中国受威胁陆栖哺乳动物为对象,建立受威胁物种的分布二值网格系统;利用Dobson算法对研究区3810个网格单元进行筛除,确定全国范围下受威胁物种的优先保护区域;结合中国主要的自然保护地分布数据(国家公园和自然保护区),采用保护空缺方法分析优先保护区内受威胁动物的保护现状。研究发现,29个50km×50km的网格单元就包含了全部的受威胁陆栖哺乳物种,其中位于喜马拉雅山东南区等地的10个网格区域覆盖有80%以上的物种,其所处的10组县级行政区内被主要自然保护地保护的土地面积占25.9%,物种数占83.6%,存在一定的保护空缺。本文采用Dobson排除算法,以小面积规则网格为基本单元,顾及到了实验结果的客观性,有助于提高优先保护区的识别效率。  相似文献   

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Naturally dynamic forests have a high proportion of biotopes with old large trees, diverse vertical and horizontal structure at multiple scales, and much dead wood. As such, they provide habitat to species and ecosystem processes that forests managed for wood production cannot provide to the same degree. Whether termed old-growth, ancient, virgin, intact, primeval or continuity forests, a major challenge and need is to map such potential high conservation value forest for subsequent inclusion in functional habitat networks for biodiversity conservation in forest landscapes. Given that the delivery time of natural forest properties is much longer than of industry wood, we explore the usefulness of using historical maps to identify forests that have been continuously present for 220 years (potential old-growth) versus 140 years (potential aging forest) in a case study in the Romanian Carpathian Mountains (see Online Resource 1). While the total forest cover increased by 35 % over the past two centuries, the area of potential aging and potential old-growth forest declined by 56 and 34 %, respectively. Spatial modelling of edge effects and patch size for virtual species with different requirements indicated an even greater decrease in the area of functional habitat networks of old-growth and ageing forest. Our analyses show that compared to simple mapping of potential high conservation forests, the area of functional habitat patches is severely overestimated, and caution is needed when estimating the area of potential high conservation value forests that form functional habitat networks, i.e. a green infrastructure. In addition, the landscape and regional scale connectivity of patches needs to be considered. We argue that the use of historical maps combined with assessment of spatial patterns is an effective tool for identifying and analyzing potential high conservation value forests in a landscape context.  相似文献   

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The cornerstone of EU nature conservation, the Natura 2000 (N2K) network is far from complete in many EU countries, including Cyprus, particularly where new datasets have become available. Thus, an important question in conservation biology is how new data can be incorporated in an effort to redesign N2K where appropriate. We analyse the efficacy of the N2K network in Cyprus, a global biodiversity hotspot, for protecting threatened vascular plants. We used 252 species for which detailed distributional data were available and added new records for 168 species. Overlaying a 1 km2 grid map for Cyprus we identified distributional hotspots of threatened species (sensu IUCN) and assessed their representation level within the N2K network. Based on new recorded data we propose IUCN status changes for 15 species. There were 60 hotspots identified (cells with more than 5 threatened species) in the central-west, south, southeast and north parts of the island. GIS analysis demonstrated that 145 out of 252 species (57.5%) occur within the N2K network, ranging from 4 to 100% of their occurrences. Τhe conservation gaps identified are related to 107 threatened species (42.5% of Red Data Book plants) which are either completely outside the N2K network or in those areas where EU legislation is not applicable due to the complex political situation on the island. The most important conservation opportunities are found in the northern part of the island, where the acquis communautaire is suspended and the UK Sovereign Base Areas, which are excluded from the Accession Treaty of Cyprus. In the area under the effective control of the Government of the Republic of Cyprus (CYGCA) there are only two important hotspots found outside the N2K network.  相似文献   

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The Forest Stewardship Council developed the concept of High Conservation Values (HCVs) as a criteria in the forest certification process in order to promote sustainable forest management. It has six major components or values and component one and two of HCVs deal with the habitat for viable populations of “rare, endemic and threatened (RET) species” using the IUCN Red List category and other national / regional / local lists. But a consistent robust methodology for identification of these areas, does not exist. The present study tried to develop for the first time, a straight forward inclusive methodology for identification of HCVAs for the RET species on a spatio-temporal scale. A total of 50 RET and other significant species (32 flora, 10 fauna and 8 avifauna) were identified after a thorough literature review, field surveys and consultations with experts. Occurrence data of the selected species was collected from different secondary sources, field surveys, institutes and scientists who have worked on them. A 10 km grid-based approach and stratified random sampling was used for the primary GPS field surveys conducted during 2018–2019. MaxEnt species distribution model (SDM) software was used based on the occurrence data and environmental variables for identification of potential suitable habitats for the selected species. Linear support vector machine (LSVM) model was used for assessing the performance of the SDMs. The performance of each SDM has been validated through Cohen's Kappa (KAPPA), true skill statistic (TSS) and receiver operating characteristics (ROC) models. The proposed methodology addresses the urgent need for a holistic and robust set of techniques to apply the HCV toolkit. This is key to identify and map HCVAs for RET species at the landscape level and can be easily adapted to and adopted at the national, regional, state or local level in India. The methods offer an efficient, reliable approach for the application of the HCV concept, elsewhere in the world.  相似文献   

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《新西兰生态学杂志》2011,20(2):215-240
Populations of ship rats (Rattus rattus), Norway rats (R. norvegicus), feral house mice (Mus musculus), stoats (Mustela erminea), weasels (M. nivalis), and ferrets (M. furo) were sampled with killtraps every three months from November 1982 to November 1987 in logged and unlogged native forest and in exotic plantations of various ages at Pureora Forest Park, central North Island. Mice (n=522 collected) were fewest in unlogged native forest, more abundant in road edge cutover forest, and most abundant in a young (5-10 year old) plantation. Traps catching most mice were set in dense ground cover under a low, sparse canopy. Ship rats (n=1793) were absent from the young plantation, present but not abundant in older exotic forest, and abundant in all native forest regardless of logging history. Traps set on warmer, steeper sites caught most ship rats, and those set in early successional habitats caught fewest. There was a marked reciprocal relationship between the distributions of ship rats and of mice: the proportion of mice in the total catch of rodents decreased significantly at the least, disturbed forest sites (P <0.001). Most (81%) Norway rats (n=43) were caught in a single trap in unlogged native forest on the bank of a stream. Stoats (n=57) were most abundant in the older exotic plantations; weasels (n=16) in the young plantation and along road edges in native forest; and ferrets (n=11) in unlogged native forest. Hedgehogs (n=290) were common in unlogged native forest far from any roads and also in older exotic forest. Our data suggest that selective logging and conversion to exotics have different effects on each of the six species we monitored. We hypothesise that (1) selective logging is likely to stimulate temporary increases in the numbers of mice and weasels, but not rats or stoats, and (2) after conversion to exotic forest, mice and occasionally weasels will be abundant at first but will gradually be replaced by ship rats and stoats as the forest matures.  相似文献   

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Primates are globally recognized as an important component of biodiversity, however, more than half of primate species in the world are threatened and agriculture expansion is one of the main threats. Brazil has one of the largest networks of protected areas (PAs) in the world, but there are some conservation gaps, such as the Amazonian savannas. We aim to identify a network of priority areas to conserve a Brazilian Amazonian savanna highly threatened by agriculture expansion, by using seven primate species and four vegetation types as targets. We constructed species distribution models (SDMs) for the primates and used a Systematic Conservation Planning approach. We defined as a quantitative conservation target the proportion of the distribution of each primate species within the network according to traits related to their vulnerability to extinction. In addition, we set a target of including at least 30% of each savanna type within priority areas. We created a map of potential use of the land for agriculture and another of environmental risk, which were included as costs in the decision process, and together with the SDMs and vegetation types, identified the network of priority areas by using the software Marxan. We evaluated the feasibility of implementing conservation actions, such as establishing Conservation Units (e.g. reserves managed by the government), or implementing community-based conservation actions in each priority area. Additionally, we estimated the economic investment (US$/year) required to establish Conservation Units across the priority areas. Conservation targets for primates and vegetation types were met by protecting 3,240 km2 of the Savannas of Amapá. An investment of approximately US$958,122/year over five years is required to turn these priority areas into Conservation Units, however, we propose other strategies such as conservation on community lands and public policies. All these strategies would allow for protecting forest cover and the heterogeneous environments that are suitable for primates and other biodiversity components.  相似文献   

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我国是全球生物多样性大国,拥有包括大熊猫、金丝猴、华南虎、麋鹿、白鱀豚等特有物种和旗舰物种在内的丰富兽类资源。近几十年来,土地利用模式转变、盗猎、环境污染、气候变化等因素使许多兽类物种面临生存威胁,导致物种遗传多样性丧失。而遗传多样性是生物多样性的基本组成部分,决定了物种和种群能否长期生存。保护遗传学作为保护生物学的一大分支学科,旨在通过遗传学分析探明种群遗传变异和物种濒危的遗传学机制。近40年来,随着研究手段和技术的不断发展,我国兽类保护遗传学在遗传多样性和近交水平评估、景观遗传学、生态遗传学和圈养种群遗传管理等方面都取得了重要成果。然而,未来人类社会发展可能为濒危兽类带来的威胁依然存在,高通量测序等新技术的进一步发展则能够帮助我们更加深入地了解濒危物种和种群遗传适应与濒危机制,从而实现对濒危兽类的有效管理与保护。  相似文献   

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中国濒危兽类保护基因组学和宏基因组学研究进展与展望   总被引:1,自引:0,他引:1  
揭示濒危兽类的演化历史、濒危机制及适应性演化策略,是保护生物学关注的重大科学问题。近十几年来,高通量测序技术的不断发展以及多学科交叉融合,为揭示濒危物种的演化历史、遗传结构、适应性演化及其与肠道微生物的协同演化的分子机制提供了重要的技术支撑,由此产生了保护基因组学和保护宏基因组学两个分支学科,为野生动物尤其是濒危动物的保护生物学研究提供了新的方向与思路。本文综述了我国在保护基因组学和保护宏基因组学领域取得的重要进展,并展望未来的发展趋势,以期进一步推动我国濒危兽类保护生物学的发展。  相似文献   

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Aim Global abundance is an important characteristic of a species that is correlated with geographical distribution and body size. Despite its importance these estimates are not available since reliable field estimates are either expensive or difficult to obtain. Based on the relationship between a species’ local abundance and distribution, some authors propose that abundance can be obtained through spatial distribution data from maps plotted at different scales. This has never been tested over the entire geographical range of a species. Thus, the aim of this study was to estimate global abundance of the Neotropical primate Brachyteles hypoxanthus (northern muriqui) and compare the results with available field estimates. Location From southern Bahia to Minas Gerais and Espírito Santo states, in the Brazilian Atlantic rain forest. Methods We compiled 25 recent occurrence localities of B. hypoxanthus and plotted them in grid cells of five different sizes (1, 25, 50, 75 and 100 km per side) to evaluate the performance and accuracy of abundance estimates over a wide range of scales. The abundance estimates were obtained by the negative binomial distribution (NBD) method and corrected by average group size to take into account primate social habits. To assess the accuracy of the method, the predicted abundances were then compared to recent independent field estimates. Results The NBD estimates were quite accurate in predicting B. hypoxanthus global abundance, once the gregarious habits of this species are taken into account. The predicted abundance estimates were not statistically different from those obtained from field estimates. Main conclusions The NBD method seems to be a quick and reliable approach to estimate species abundance once several limiting factors are taken into account, and can greatly impact conservation planning, but further applications in macroecological and ecological theory testing needs improvement of the method.  相似文献   

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The 2007 Energy Independence and Security Act mandates a five‐fold increase in US biofuel production by 2022. Given this ambitious policy target, there is a need for spatially explicit estimates of landscape suitability for growing biofuel feedstocks. We developed a suitability modeling approach for two major US biofuel crops, corn (Zea mays) and switchgrass (Panicum virgatum), based upon the use of two presence‐only species distribution models (SDMs): maximum entropy (Maxent) and support vector machines (SVM). SDMs are commonly used for modeling animal and plant distributions in natural environments, but have rarely been used to develop landscape models for cultivated crops. AUC, Kappa, and correlation measures derived from test data indicate that SVM slightly outperformed Maxent in modeling US corn production, although both models produced significantly accurate results. When compared with results from a mechanistic switchgrass model recently developed by Oak Ridge National Laboratory (ORNL), SVM results showed higher correlation than Maxent results with models fit using county‐scale point inputs of switchgrass production derived from expert opinion estimates. However, Maxent results for an alternative switchgrass model developed with point inputs from research trial sites showed higher correlation to the ORNL model than the corresponding results obtained from SVM. Further analysis indicates that both modeling approaches were effective in predicting county‐scale increases in corn production from 2006 to 2007, a time period in which US corn production increased by 24%. We conclude that presence‐only methods are a powerful first‐cut tool for estimating relative land suitability across geographic regions in which candidate biofuel feedstocks can be grown, and may also provide important insight into potential land‐use change patterns likely to be associated with increased biofuel demand.  相似文献   

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When modelling the distribution of a species, it is often not possible to comprehensively sample the whole distribution of the species and managers may have habitat models based on data from one area that they want to apply in other areas. Hence, an important question is: how accurate are models of the distributions of species when applied beyond the areas where they were developed? A first step in measuring model transferability could be testing models in adjacent areas. We predicted the habitat associations of the brush‐tailed rock‐wallaby (Petrogale penicillata) across two spatial scales in two neighbouring study areas in eastern Australia, south‐east Queensland and north‐east New South Wales. We used classification trees for exploratory data analysis of habitat relationships and then applied logistic regression models to predict species occurrence. We assessed the within‐area discriminative ability of the habitat models using cross‐validation and threshold plots, and tested the predictive ability of the models for adjacent areas using the receiver operating characteristic statistic to determine the area under the curve. We found that models performed well within an area and extrapolating them to adjacent areas resulted in good predictive performance at the site scale but substantially poorer predictive performance at the landscape scale. We conclude that distribution models for wildlife species should only be extrapolated to neighbouring areas with caution when using landscape‐scale environmental variables. Alternatively, only key habitat associations predicted by the models at this scale should be transferred across adjacent areas once verified against local knowledge of the ecology of the study species.  相似文献   

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Many areas of tropical rainforest have been fragmented and the habitat quality of fragments is often poor. For example, on Borneo, many forest fragments are highly degraded by repeated logging of Dipterocarpaceae trees prior to fragmentation, and we examined the viability of enrichment planting as a potential management tool to enhance the conservation value of these forest fragments. We planted seedlings of three dipterocarp species with contrasting light demands and tolerances (Parashorea malaanonan (light demander), Dryobalanops lanceolata (intermediate), Hopea nervosa (shade tolerant)) in eight forest fragment sites (3–3529 ha), and compared seedling performance with four sites in continuous forest. Eighteen months after planting, survival rates of seedlings were equally high in fragment sites (mean survival = 63 %), and in continuous forest sites (mean survival = 68 %). By contrast, seedling growth and herbivory rates were considerably higher in fragments (by 60 % for growth and 45 % for herbivory) associated with higher light environments in degraded forest fragments compared with continuous forest sites. Among the three study species, H. nervosa seedlings had the highest survival rates overall, and P. malaanonan seedlings generally grew fastest and suffered highest herbivory rates. There were no interactions between species performance and the effects of fragment site area, forest structure or soil characteristics of sites suggesting that the three species responded similarly to fragmentation effects. High survival of planted seedlings implies that enrichment planting would be a successful forest management strategy to improve forest quality, and hence conservation value, of fragments.  相似文献   

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为了实现利用最小的保护成本满足最大限度的保护物种需求,本文以我国陆生濒危哺乳动物为主要研究对象,以1,434个生态功能小区为规划单元,在地理信息系统(geographic information system,GIS)支持下,确定了94种陆生濒危哺乳动物的潜在分布,利用C-Plan软件的迭代统计分析功能,确定了1,434个陆地生态功能小区作为规划单元的不可替代性值(Irreplaceable,IR).研究将高不可替代性值的规划单元划分为必须保护规划单元(mandatory reserve,MR) (20个)、协商保护规划单元(negotiable reserve,NR) (29个)和部分保护规划单元(partially reserve,PR)(40个)3种不同类型的优先保护等级,面积分别占全国生态功能区总面积的2.2%、6.0%和11.8%,可实现近98%的陆生濒危哺乳动物保护需求.研究结合规划单元内的生态敏感性和保护优先性,提出了基于陆生濒危哺乳动物保护的89个生态功能小区的优先保护规划建议.本研究在丰富系统保护规划理论的同时进行了有益的实践和应用研究,其结果可为我国陆地生态功能区的优先保护规划和陆生濒危哺乳动物的保护提供科学依据.  相似文献   

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ABSTRACT The Wattled Curassow (Crax globulosa) is a globally threatened species restricted to humid várzea forest (seasonally flooded forest along white‐water rivers) in low‐lying regions of Amazonia. The Wattled Curassow were thought to have been extirpated from the Beni area of Bolivia, but were rediscovered near the Río Negro River in 2001. Our objectives were to determine the size of this population, examine habitat use, and based on our results, assess the conservation status of the Wattled Curassow. During July and August 2006, we used distance sampling to estimate the population density in our study area. We estimated the density of Wattled Curassows at 3.4 (95% CI: 1.4–8.1) individuals/km2 and all were observed within 300 m of the river. Based on the availability of suitable habitat (18 km2 of riparian várzea habitat within 300 m of the river), we estimated that the breeding population of Wattled Curassows in our study area consisted of 61 individuals. The specialized habitat requirements of the Wattled Curassow has important conservation implications because previous population estimates were based on the availability of várzea forest rather than the availability of water edge habitat within várzea forest. As a result, the current global population estimate (2500–9999) is higher than our estimate (500–2500) that takes the specialized habitat requirements of the Wattled Curassow into account. Given this low estimated population, along with the severely fragmented state of the few remaining populations and their dependence on a specialized and vulnerable habitat, we recommend that the status of the Wattled Curassow be upgraded from Vulnerable to Endangered.  相似文献   

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Loss and degradation of natural habitats and their biodiversity may, arguably, be mitigated or compensated through the creation of human-engineered habitats: the underlying conservation tenet is that these artificial habitats compensate for diminished diversity caused by human impacts at local or regional scales. This approach is widely used in the sea by purposefully scuttling ships to create artificial reefs, but its performance as a conservation tool is seldom critically examined in these situations. Here we test if the diversity of sessile invertebrate assemblages on a large, but young (3 years), artificial reef, created by sinking a 133 m long battle ship off Eastern Australia, can mimic that of nearby natural reefs. We use this system as a model to test whether this artificial reef can form compensatory habitat of comparable quality and levels of biodiversity. Our assessment is based on the abundance, species richness, and species composition of sessile invertebrate assemblages, including corals. Despite some signs that temporal trajectories of ecological metrics, such as cover, began to approach natural conditions after 3 years, the ecological structure of sessile invertebrate assemblages on this young wreck remained fundamentally different from those on nearby natural reefs. In particular, large, long-lived corals were abundant on natural rocky reefs, but were rare and covered little area on the young wreck. These data demonstrate that when trajectories to community convergence with natural habitats are prolonged, as may be the case here, any compensatory effects of artificial habitats will have a considerable time lag. Such lags have implications for appraising the conservation value of wrecks and artificial reefs, and they emphasize the need to explicitly acknowledge temporal dynamics when using artificial habitats as complementary conservation tools to augment larger conservation efforts on natural systems.  相似文献   

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Background

The Center for Disability Resources (CDR) Library is the largest collection of its kind in the Southeastern United States, consisting of over 5,200 books, videos/DVDs, brochures, and audiotapes covering a variety of disability-related topics, from autism to transition resources. The purpose of the library is to support the information needs of families, faculty, students, staff, and other professionals in South Carolina working with individuals with disabilities. The CDR Library is funded on a yearly basis; therefore, maintaining high usage is crucial. A variety of promotional efforts have been used to attract new patrons to the library. Anyone in South Carolina can check out materials from the library, and most of the patrons use the library remotely by requesting materials, which are then mailed to them. The goal of this project was to identify areas of low geographic usage as a means of identifying locations for future library marketing efforts.

Methods

Nearly four years worth of library statistics were compiled in a spreadsheet that provided information per county on the number of checkouts, the number of renewals, and the population. Five maps were created using ArcView GIS software to create visual representations of patron checkout and renewal behavior per county.

Results

Out of the 46 counties in South Carolina, eight counties never checked out materials from the library. As expected urban areas and counties near the library's physical location have high usage totals.

Conclusion

The visual representation of the data made identification of low usage regions easier than using a standalone database with no visual-spatial component. The low usage counties will be the focus of future Center for Disability Resources Library marketing efforts. Due to the impressive visual-spatial representations created with Geographic Information Systems, which more efficiently communicate information than stand-alone database information can, librarians may benefit from the software's use as a supplemental tool for tracking library usage and planning promotional efforts.
  相似文献   

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