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1.
GeoCAT is an open source, browser based tool that performs rapid geospatial analysis to ease the process of Red Listing taxa. Developed to utilise spatially referenced primary occurrence data, the analysis focuses on two aspects of the geographic range of a taxon: the extent of occurrence (EOO) and the area of occupancy (AOO). These metrics form part of the IUCN Red List categories and criteria and have often proved challenging to obtain in an accurate, consistent and repeatable way. Within a familiar Google Maps environment, GeoCAT users can quickly and easily combine data from multiple sources such as GBIF, Flickr and Scratchpads as well as user generated occurrence data. Analysis is done with the click of a button and is visualised instantly, providing an indication of the Red List threat rating, subject to meeting the full requirements of the criteria. Outputs including the results, data and parameters used for analysis are stored in a GeoCAT file that can be easily reloaded or shared with collaborators. GeoCAT is a first step toward automating the data handling process of Red List assessing and provides a valuable hub from which further developments and enhancements can be spawned. 相似文献
2.
Recent efforts to improve the representation of plant species included on the IUCN Red List of Threatened Species through the IUCN Sampled Red List Index (SRLI) for Plants have led to the assessment of almost 1000 additional species of pteridophytes and lycophytes under IUCN Red List criteria. Species were selected at random from all lineages of pteridophytes and lycophytes and are taxonomically as well as ecologically representative of pteridophyte and lycophyte diversity. 16% of pteridophyte and lycophyte species are globally threatened with extinction and 22% are of elevated conservation concern (threatened or Near Threatened); of species of pteridophytes and lycophytes previously included on the Red List, 54% were considered threatened. Over half of pteridophyte and lycophyte species assessed for the SRLI use estimates of range size; therefore the method used to measure range may affect the Red List category assigned. We evaluated this using two alternative metrics for estimating range, species distribution modelling (SDM) and ecologically suitable habitat (ESH), for 227 species endemic to the Neotropical biogeographic realm. Differences between range estimates were small when ranges were small but increased with increasing range size. For 58 (25.6%) species alternative modelling techniques result in the species meeting the threshold for a different IUCN Red List category from using extent of occurrence. Modelling threatened species distributions also highlights priority areas for conservation in tropical and subtropical montane forests that are the most species-rich habitat for small-range pteridophyte and lycophyte species, but which are now increasingly subject to rapid conversion to agriculture. 相似文献
3.
Michael J. Jowers Santiago Sánchez-Ramírez Mark S. Greener Lynsey R. Harper Renoir J. Auguste Trudie Marshall Robyn Thomson Isabel Byrne Ciara F. Loughrey Leah Graham William A. O. McGhee John C. Murphy Gilson A. Rivas Cammy Beyts J. Roger Downie 《Population Ecology》2022,64(2):136-149
Trinidad and Tobago are home to three endemic species in the anuran genus Pristimantis, of which two (Pristimantis charlottevillensis and Pristimantis turpinorum) occur in Tobago alone and the third (Pristimantis urichi) is present on both islands. Earlier, the IUCN assessed the conservation status of these species as: P. urichi, Endangered (EN); P. charlottevillensis, Least Concern (LC); P. turpinorum, Vulnerable (VU). However, these assessments were based on very little field-based evidence. Here, we present survey results which contributed to reassessments as LC, VU and Data Deficient for these three species, respectively. Despite the close proximity of Trinidad to northern Venezuela, the islands do not share any Pristimantis species with the mainland, which holds a rich endemicity of Pristimantis regionally. In this study, we used genetic sequencing from several island populations and compared them to northern Venezuelan endemics to assess genetic divergence for the first time. The time tree analyses found that only the northern Tobago species P. turpinorum is closely related to mainland Pristimantis, with a genetic split dating to the Late Miocene, suggesting a vicariant event of mainland and island species. Pristimantis urichi, although identical between the two islands, remains highly divergent from the mainland species. Similar results were found for P. charlottevillensis. In addition, there was a high level of divergence between P. urichi and P. charlottevillensis. These findings indicate different island colonization events by different lineages. Sequencing other Venezuelan species remains pivotal to unravel the complexity of the colonization episodes in the region, likely influenced by the changing topography and multiple connection and isolation episodes of the islands by eustatic sea-level changes. 相似文献
4.
Defining a role for herbarium data in Red List assessments: a case study of Plectranthus from eastern and southern tropical Africa 总被引:6,自引:6,他引:0
Red Lists are widely used to indicate species at risk of extinction. Specimen sheets in herbaria provide an important source of data relevant for Red List assessments. The aims of this paper are to establish which data can be sourced from specimen information to satisfy IUCN Red Data List criteria and to identify the specific criteria that can be used. Red List parameters are measured within a Geographical Information System (GIS), as this provides an objective and repeatable methodology which is less subjective than manual methods. Data used to explore this were gathered during the course of preparing a monograph on Plectranthus (Lamiaceae). Criteria relating to distribution (extent of occurrence, area of occupancy and fragmentation) and population profile (projected continuing decline and number of subpopulations) proved most suitable for assigning categories of threat. Estimates of mature individuals, generation length, population size, population reduction, extreme fluctuation and number of locations could not be derived from herbarium material without making inconsistent subjective decisions. In addition to comprehensively databased specimen information, extensive field knowledge is required to produce better estimates for assessing extinction risk. In order to enhance the usefulness of specimen information in the future, improvements in recording additional botanical data at the time of collection would be beneficial. Overall, herbaria provide a useful starting point for conservation-related work and can help to guide future work. 相似文献
5.
江苏珍稀濒危植物的多样性、分布及保护 总被引:1,自引:0,他引:1
掌握重点保护野生植物的濒危现状及评估濒危等级是制定科学保护策略的关键。根据江苏第二次重点保护野生植物资源调查(2012-2018)以及近年来相关调查资料, 我们采用世界自然保护联盟(IUCN)物种红色名录的濒危等级与评估标准, 对江苏分布的珍稀濒危植物的现状与濒危等级进行了评估与分析。结果表明: (1)江苏41种国家重点保护和濒危野生植物的濒危等级可以分为7个等级。包括地区灭绝(RE) 2种, 占总种数的4.88%; 极危(CR) 10种, 占24.39%; 濒危(EN) 6种, 占14.63%; 易危(VU) 13种, 占31.71%; 近危(NT) 2种, 占4.88%; 无危(LC) 2种, 占4.88%; 数据缺乏(DD) 6种, 占14.63%。其中, 受威胁物种(包括CR、EN和VU)有29种, 占总种数的70.73%。(2)建议的江苏重点保护野生植物有74种, 隶属于40科62属; 它们的受威胁比例较高, 达74.32%。江苏人口众多、环境资源压力较大, 近年来生产经营和土地利用方式的改变以及宣传教育不足很可能是导致这些原生物种濒危的主要原因。因此建议: (1)尽快制定江苏省级重点保护野生植物名录; (2)加强科学研究, 同时对部分濒危植物进行就地保护和迁地保护, 积极开展野外回归、近地保护和动态监测; (3)继续加大对重点保护野生植物的保护管理和宣传力度。 相似文献
6.
IUCN Red List assessment of the Cape Verde endemic flora: towards a global strategy for plant conservation in Macaronesia 下载免费PDF全文
Maria M. Romeiras Silvia Catarino Isildo Gomes Claudia Fernandes Jose C. Costa Juli Caujapé‐Castells Maria Cristina Duarte 《Botanical journal of the Linnean Society. Linnean Society of London》2016,180(3):413-425
We review the conservation status and threats to the endemic vascular flora of the Cape Verde islands, mostly based on the past two decades of collecting, literature review and herbarium specimens. The application of IUCN Red List criteria and categories using RAMAS software reveals that 78% of the endemic plants are threatened (29.3% Critically Endangered, 41.3% Endangered, 7.6% Vulnerable). Most of these endemics have a limited geographical range, and half of them have Areas of Occupancy and Extents of Occurrence of < 20 and 200 km2, respectively. Our data show that, over the last two decades, the Cape Verde vascular plants have become more threatened and their conservation status has declined, mostly as a consequence of the increase in exotic species, habitat degradation and human disturbance. This paper presents the first comprehensive IUCN Red List data review for the plants endemic to Cape Verde, thus providing an important step towards the recognition and conservation of its threatened endemic flora at the national and global level. It also fills a knowledge gap, as it represents the first thorough assessment of the conservation status of the entire endemic flora of a Macaronesian archipelago. 相似文献
7.
Green Plants in the Red: A Baseline Global Assessment for the IUCN Sampled Red List Index for Plants
《PloS one》2015,10(8)
Plants provide fundamental support systems for life on Earth and are the basis for all terrestrial ecosystems; a decline in plant diversity will be detrimental to all other groups of organisms including humans. Decline in plant diversity has been hard to quantify, due to the huge numbers of known and yet to be discovered species and the lack of an adequate baseline assessment of extinction risk against which to track changes. The biodiversity of many remote parts of the world remains poorly known, and the rate of new assessments of extinction risk for individual plant species approximates the rate at which new plant species are described. Thus the question ‘How threatened are plants?’ is still very difficult to answer accurately. While completing assessments for each species of plant remains a distant prospect, by assessing a randomly selected sample of species the Sampled Red List Index for Plants gives, for the first time, an accurate view of how threatened plants are across the world. It represents the first key phase of ongoing efforts to monitor the status of the world’s plants. More than 20% of plant species assessed are threatened with extinction, and the habitat with the most threatened species is overwhelmingly tropical rain forest, where the greatest threat to plants is anthropogenic habitat conversion, for arable and livestock agriculture, and harvesting of natural resources. Gymnosperms (e.g. conifers and cycads) are the most threatened group, while a third of plant species included in this study have yet to receive an assessment or are so poorly known that we cannot yet ascertain whether they are threatened or not. This study provides a baseline assessment from which trends in the status of plant biodiversity can be measured and periodically reassessed. 相似文献
8.
Janice S. Golding 《Biodiversity and Conservation》2004,13(4):773-780
Information contained on specimen labels of natural history collections is often the most reliable and available source of information to guide conservation decisions. When used for making IUCN Red List assessments, the inherent limitations associated with specimen information affect the assignment of Red List categories, and the case of the southern African plant Red Lists reflects this. Red List assessments that are based on specimen information can result in predictable outcomes, namely the tendency to assign the following categories: Data Deficient, Lower Risk-least concern, Vulnerable D2 or a threatened category using Criterion B. The reason for this is that specimen information satisfies distribution parameters of the IUCN system more readily than demographic parameters. 相似文献
9.
Manuela Sim-Sim Sara Ruas Susana Fontinha Lars Hedenäs Cecília Sérgio Carlos Lobo 《分类学与生物多样性》2013,11(3):315-330
On oceanic islands, the evolution of plants and animals with particular characteristics is favoured due to their isolation, populations normally comprising a large number of unique, endemic species. The Madeira and Selvagens archipelagos are considered biodiversity hotspots, containing an especially rich bryoflora. Due to its characteristically small size, this taxonomic group does not get much attention in conservation programmes. However, these plants are an important component of terrestrial ecosystems, representing a major part of biodiversity and playing a vital role in the ecosystem's functioning. As such, the development of the first Red List for Madeira and Selvagens Archipelagos has the potential to guide conservation efforts focused on taxa and habitats where threatened species and endemics are better represented. By applying the International Union for Conservation of Nature and Natural Resources (IUCN) criteria, recently revised to apply to small islands, it was possible to obtain the percentage of threatened taxa present in the archipelagos (23.6%), and for each habitat type. It was verified that high mountain habitats and the Laurel forest represent areas that host higher percentages of threatened taxa (29.5% and 22.2%). An important result of the present Red List is the identification of hotspots for bryophyte diversity, supporting the definition of reserves/microreserves. The information obtained can also be linked up with the Red Lists of other taxonomic groups to work towards the definition of a more holistic conservation strategy. 相似文献
10.
Jon Paul Rodríguez David A. Keith Kathryn M. Rodríguez-Clark Nicholas J. Murray Emily Nicholson Tracey J. Regan Rebecca M. Miller Edmund G. Barrow Lucie M. Bland Kaia Boe Thomas M. Brooks María A. Oliveira-Miranda Mark Spalding Piet Wit 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2015,370(1662)
The newly developed IUCN Red List of Ecosystems is part of a growing toolbox for assessing risks to biodiversity, which addresses ecosystems and their functioning. The Red List of Ecosystems standard allows systematic assessment of all freshwater, marine, terrestrial and subterranean ecosystem types in terms of their global risk of collapse. In addition, the Red List of Ecosystems categories and criteria provide a technical base for assessments of ecosystem status at the regional, national, or subnational level. While the Red List of Ecosystems criteria were designed to be widely applicable by scientists and practitioners, guidelines are needed to ensure they are implemented in a standardized manner to reduce epistemic uncertainties and allow robust comparisons among ecosystems and over time. We review the intended application of the Red List of Ecosystems assessment process, summarize ‘best-practice’ methods for ecosystem assessments and outline approaches to ensure operational rigour of assessments. The Red List of Ecosystems will inform priority setting for ecosystem types worldwide, and strengthen capacity to report on progress towards the Aichi Targets of the Convention on Biological Diversity. When integrated with other IUCN knowledge products, such as the World Database of Protected Areas/Protected Planet, Key Biodiversity Areas and the IUCN Red List of Threatened Species, the Red List of Ecosystems will contribute to providing the most complete global measure of the status of biodiversity yet achieved. 相似文献
11.
Xianjun Peng Jiancheng Zhao Lin Li Yongzhen Sun Yulu Niu Xiaoli Guo 《Frontiers of Biology in China》2008,3(2):176-186
Some plants of Hebei Province in China are under threat from human activities, such as over-herding and over-exploitation
of wild medicinal plants and industrial plants, etc. To identify the plants in danger in the province and to inspect the quality
of the environment encompassing Beijing and Tianjin, a red list of the threatened flora of Hebei Province was produced by
using the IUCN Red List Criteria (version 3.1) and its guidelines (version 6.2). Some 262 species were assessed and the results
were as follows: (1) the threatened flora include 211 species, accounting for 7.95% of the total native vascular plants. Among
them, 44 are Critically Endangered, 80 Endangered and 87 Vulnerable; (2) the destruction of the habitat caused by human activities
and the actual or potential exploitation of the plants themselves were the main threat factors of Hebei flora; (3) most of
the threatened plants are located in the western, northern and northeastern mountainous regions, namely the key regions of
Hebei plant diversity; the endemic and regionally endemic species are severely threatened. Consequently, the assessment not
only presented the threatened status of Hebei flora but also indicated the relatively fragile health status of the environment
of Beijing and Tianjin. Thus, it is suggested that the application of the IUCN Red List Criteria at the regional level, as
an index, could reflect the health status of the local ecosystem. In addition, more concrete measures are needed to conserve
the plant diversity and the natural ecosystem of Hebei Province and even the whole region encompassing Beijing and Tianjin. 相似文献
12.
Some plants of Hebei Province in China are under threat from human activities,such as over-herding and over-exploitation of wild medicinal plants and industrial plants,etc.To identify the plants in danger in the province and to inspect the quality of the environment encompassing Beijing and Tianjin,a red list of the threatened flora of Hebei Province was produced by using the IUCN Red List Criteria (version 3.1) and its guidelines (version 6.2).Some 262 species were assessed and the results were as follows:(1) the threatened flora include 211 species,accounting for 7.95% of the total native vascular plants.Among them,44 are Critically Endangered,80 Endangered and 87 Vulnerable;(2) the destruction of the habitat caused by human activities and the actual or potential exploitation of the plants themselves were the main threat factors of Hebei flora;(3) most of the threatened plants are located in the western,northern and northeastern mountainous regions,namely the key regions of Hebei plant diversity;the endemic and regionally endemic species are severely threatened.Consequently,the assessment not only presented the threatened status of Hebei flora but also indicated the relatively fragile health status of the environment of Beijing and Tianjin.Thus,it is suggested that the application of the IUCN Red List Criteria at the regional level,as an index,could reflect the health status of the local ecosystem,In addition,more concrete measures are needed to conserve the plant diversity and the natural ecosystem of Hebei Province and even the whole region encompassing Beijing and Tianjin. 相似文献
13.
生物多样性为人类提供了生存所必需的一系列生态系统服务和功能。然而,由于人为活动的加剧,生物多样性不断丧失。传统的生物多样性保护主要关注物种多样性,存在着对生物多样性的代表性不足,不能及时反应生态系统多样性的变化等缺点。近年来,生态系统层次上的多样性保护成为研究热点,一些国家和组织相继开展了大尺度的生态系统评估工作。文章回顾了已有的生态系统评估方案,发现当前生态系统评估多采用IUCN物种红色名录的分级标准体系,主要评估生态系统的濒危程度,评估标准主要是分布范围和功能的变化,不同评估方案采用的指标和阈值有差异,需要建立统一的生态系统分类体系和评价方案。同时,结合国内生态系统评价的现状,提出了在我国开展生态系统红色名录研究的若干可行建议。 相似文献
14.
Richard B Sherley Robert JM Crawford Bruce M Dyer Jessica Kemper Azwianewi B Makhado Makhudu Masotla 《Ostrich》2019,90(4):335-346
The Cape Gannet Morus capensis is one of several seabird species endemic to the Benguela upwelling ecosystem (BUS) but whose population has recently decreased, leading to an unfavourable IUCN Red List assessment. Application of ‘JARA’ (‘Just Another Red-List Assessment,’ a Bayesian state-space tool used for IUCN Red List assessments) to updated information on the areas occupied by Cape Gannets and the nest densities of breeding birds at their six colonies, suggested that the species should be classified as Vulnerable. However, the rate of decrease of Cape Gannets in their most-recent generation exceeded that of the previous generation, primarily as a result of large decreases at Bird Island, Lambert’s Bay, and Malgas Island, off South Africa’s west coast (the western part of their range). Since the 1960s, there has been an ongoing redistribution of the species from northwest to southeast around southern Africa, and ~70% of the population now occurs on the south coast of South Africa, at Bird Island in Algoa Bay, on the eastern border of the BUS. Recruitment rather than adult survival may be limiting the present population; however, information on the seabird’s demographic parameters and mortality in fisheries is lacking for colonies in the northern part of the BUS. Presently, major threats to Cape Gannet include: substantially decreased availability of their preferred prey in the west; heavy mortalities of eggs, chicks and fledglings at and around colonies, inflicted by Cape Fur Seals Arctocephalus pusillus and other seabirds; substantial disturbance at colonies caused by Cape Fur Seals attacking adult gannets ashore; oiling; and disease. 相似文献
15.
William R. T. Darwall Caroline M. Pollock Kevin G. Smith Jean-Christophe Vié 《Diversity & distributions》2008,14(1):159-160
De Silva et al . (2007) present an overview of the distribution and conservation status of the endemic freshwater fish of Asia. Within that review they use data from the IUCN Red List of Threatened Species™ (2006) to conduct an analysis of the conservation status of those endemic fish species. Their analysis is incorrect and provides a very misleading impression of the level of threat to Asian freshwater fish and to freshwater fish at the global scale. The errors stem from a misinterpretation of the data presented on the IUCN Red List. The sources of errors are discussed below and the opportunity is taken to clarify what the information on the IUCN Red List represents. 相似文献
16.
We assessed the size of the population of the African Softshell Turtle, Trionyx triunguis, in Dalaman (Mu?la, Turkey), which is considered to be the largest population of the species in the Mediterranean, by using the Jolly-Seber mark-recapture method. A total of 415 individuals were caught during the summer months of 2009 to 2011, of which 148 were recaptures. From 267 marked individuals, 148 (55%) were male, 69 (26%) were female and 50 (19%) were juveniles and subadults of indeterminate sex. The male:female ratio was calculated to be 2.14:1. By using Model A' of the Jolly-Seber mark-recapture method, which includes deaths but no immigration, the mean population size in Kükürt and Küçükdalyan (Karg?n) lakes, together with Tersakan and Ta?l?çay creeks, were estimated to be 396±36. Based on this estimation, the population density was calculated to be 14 turtles/ha. Approximately 67.4% of the estimated population was marked. The mean capture probability (p) and mean survival ratio (Φ) were 0.094±0.009 and 0.957±0.076, respectively. Our results showed that the species’ population size is larger than previously estimated based on visual counts. The status “Vulnerable” C2a of the IUCN Red Data Book categories seems therefore more appropriate for the Mediterranean subpopulation of Trionyx triunguis than “Endangered” C2a. 相似文献
17.
The Global Strategy for Plant Conservation calls for a preliminary assessment of the conservation status of all known plant species by the year 2010. To date insufficient progress has been made on meeting this target. New efforts to develop a preliminary list beyond using the full IUCN criteria in plant assessments are needed. Here we present an algorithm that provides a preliminary assessment of the conservation status of plant species using data from herbarium specimens. We use Hawaiian specimen data from the United States National Herbarium to calibrate the parameters of the algorithm and then use specimen data from the Arecaceae, Commelinaceae, Gesneriaceae and Heliconiaceae as examples of the application of the algorithm. The algorithm was calibrated to insure 95% accuracy in placing the Hawaiian plant species into previously and independently determined threatened categories. Our results indicate that 28% of the Hawaiian taxa, 27% of the species of Arecaceae, 45% of the species of Commelinaceae, 32% of the species of Gesneriaceae, and 35% of the species of Heliconiaceae are Not Threatened and will not need any further evaluation for the preliminary assessment. Species identified here as Potentially Extinct and Potentially Threatened can be further assessed by additional herbarium material and/or conservation specialists for final evaluation using other assessment strategies (e.g., regional and national lists, taxonomic expert assessment, etc.). 相似文献
18.
The Sungazer (Smaug giganteus) is a threatened lizard species endemic to the Highveld grasslands of South Africa. The species faces risks from habitat loss and fragmentation, and illegal harvesting for traditional medicine and the pet trade. Despite these threats, the current conservation status of the species was poorly validated. We visited 79 Sungazer populations recorded in 1978 to assess population change since the initial surveys, and surveyed an additional 164 sites to better define the distribution and estimate the current population size. We interrogated all known historical trade data of the species. One-third of Sungazer populations have been extirpated over the past 37 years. The distribution includes two allopatric populations, with the smaller Mpumalanga population experiencing a significantly higher decline. The species has an extent of occurrence (EOO) of 34 500 km2, and an area of occupancy (AOO) of 1149 km2. The interpreted distribution is 17 978 km2, and just under 60% remains untransformed grassland. We estimate a population size of 677 000 mature individuals, down 48% from the estimated historical population, prior to commercial agricultural development. A total of 1194 live Sungazers were exported under permit from South Africa between 1985 and 2014, with a significant increase in numbers exported over the last decade. Without any evidence of captive breeding, we believe that these animals are all wild-caught. Based on the AOO, level of decline, fragmentation within the distribution and suspected level of exploitation, we recommend classification of the species as Vulnerable under IUCN Red List Criteria A2acd and B2ab(ii–v). The establishment of a protected area network, genetic research and further investigations into the pet and traditional medicine trades are urgently needed. 相似文献
19.
Application to the terrestrial vertebrates of Italy of a system proposed by IUCN for a new classification of national Red List categories 总被引:1,自引:0,他引:1
The criteria for classification set down in the new system of the IUCN Red List categories were applied to national distribution areas. Application of the new criteria to national distribution areas calls for an estimate of the rate of immigration. Classification was applied to the Italian autochthonous terrestrial vertebrate species that reproduce in Italy (Amphibia, Reptilia, Aves and Mammalia). Species with both marine and land habitats were included, but Cetaceans were excluded. Eighty-eight species of the autochthonous species that reproduce in Italy were classified in the threatened categories at the national level. One of the main purposes of the present classification of the risk of extinction in national distribution areas is to provide the information needed to define global conservation priorities of species present on national territory. The species nationally and/or globally endangered or at lower risk were grouped into four priority classes, on the basis of their reproductive phenology on national territory and the size of temporarily present contingents. Of the 551 species present regularly or seasonally on Italian territory, 149 (27.0%) are in the initial indicative list of conservation priorities. 相似文献
20.
景观保护与受胁景观红皮书 总被引:15,自引:0,他引:15
地球上大多数景观是自然过程与人类文化过程交互作用的产物,是长期适应和演化形成的稳定类型。它们可以作为协调人类与环境相互关系的模型,具有十分重要的科学、文化和示范价值。但近几十年来,随着人口的快速增长,新技术的采用,世界各地的景观正受到严重威胁,使它们面临退化,有些走向消失。保护和抢救一部分有价值的景观已成为当前的紧迫任务。
国际上于1991年在 IUCN 的 CESP 内成立了“景观保护工作组”,制定了“景观保护计划”,接着在意大利和英国分别举行了两次景观保护专题讨论会,并在希腊克里特岛开展了事例研究。现正着手编制事例研究地点的《受胁景观红皮书》和世界范围的《濒危景观红色名录》。 相似文献