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1.
The concept of “areas of endemism”, and the assumption that these patterns are always a consequence of vicariant events, are reviewed. This assumption is related to the idea that areas of endemism have well-defined limits and never share any surface with other areas of endemism because they must represent sister areas supported by sister taxa. Based on this idea, overlapping areas have been considered rarely, or ignored completely. Using a data set of mammals of North America, we test here whether the overlapping areas are indeed sister areas supported by sister taxa, thus evaluating whether vicariant events are commonly the factor producing areas of endemism.  相似文献   

2.
欧阳晓  朱翔  贺清云 《生态学报》2019,39(20):7502-7513
探索生态系统服务与城市化的空间交互关系为城市发展和保护提供新的视角。以长株潭城市群为例,以其2015年的土地利用、经济社会等数据为基础,利用格网分析和空间自相关模型解析城市化与生态系统服务的空间交互规律。结果表明:(1)长株潭城市群城市化水平空间分布区域差异性显著,城市化水平由高到低依次为城市化地区、正在城市化地区和生态绿心保护区,表现出从城市化地区向周边地区依次递减的态势。(2)受城市化水平和土地利用变化等影响,生态系统服务空间分布具有明显的差异性,并呈现出"中心-外围"逐步升高的趋势。(3)长株潭城市群城市化与各项生态系统服务之间呈显著负相关,由于驱动机制的不同,城市化地区、正在城市化地区和生态绿心保护区的城市化对生态系统服务的影响存在显著差异。(4)长株潭城市群的各项生态系统服务与城市化之间存在四种空间相关类型。高高集聚区和低低集聚区零散分布在整个研究区域,面积较小;高低集聚区分布在湘潭县西南部、株洲县东南部,面积较大;低高集聚区分布集中在城市化地区,呈现块状分布,面积较大。  相似文献   

3.
厦门市重点保护植物空间优先保护格局研究   总被引:1,自引:1,他引:0  
钱灵颖  黄智洵  杨盛昌  曹文志 《生态学报》2021,41(11):4367-4378
生物多样性保护对维持城市生态系统功能具有重要意义。以39种厦门市重点保护植物为对象,通过物种分布模型MaxENT获得物种潜在分布栅格图,利用空间保护优先化定量工具Zonation软件识别理论上既适宜重点保护植物生存又能够保证景观连通性的区域,获得本地重点保护植物景观保护等级。根据2020年全球生物多样性目标,将景观保护等级最高的17%区域视为多物种空间优先保护区,结合Zonation模型生成的随景观丧失物种加权灭绝风险曲线,将保护等级最高的8%区域划为一级保护区,保护等级在8%-17%范围内的区域划为二级保护区。利用MaxENT模型中的jackknife刀切法发现海拔是对本地重点保护植物分布影响最大的环境因子,优先保护区集中分布于海拔较低的海岸带区域。将优先保护区与自然保护地建设现状、厦门市生态功能区规划、土地利用规划、城市总体规划对比发现厦门市岛外西部、北部的优先保护区得到了较好保护;岛外的西南部及东南部、岛内的东部及南部海岸带的优先保护区被建设用地大规模占用,已纳入自然保护地范围的区域较少,存在大量的海岸带优先保护区保护空缺;岛外东南部的部分优先保护区虽未被占用,但规划中属发展备用地,缺乏生态保护。为避免优先保护区面积的进一步萎缩,应重点关注海岸带区域优先保护区的生态保护,将目前属于发展备用地的优先保护区转划为生态留白空间,针对一级、二级优先保护区分别实施刚性和弹性的生态保育措施,在保护生物多样性的同时,严控对海岸带区域优先保护区的进一步开发利用,协调优先保护区内保护与开发利用间的关系。  相似文献   

4.
Climate change threatens European conservation areas   总被引:4,自引:0,他引:4  
Europe has the world's most extensive network of conservation areas. Conservation areas are selected without taking into account the effects of climate change. How effectively would such areas conserve biodiversity under climate change? We assess the effectiveness of protected areas and the Natura 2000 network in conserving a large proportion of European plant and terrestrial vertebrate species under climate change. We found that by 2080, 58?±?2.6% of the species would lose suitable climate in protected areas, whereas losses affected 63?±?2.1% of the species of European concern occurring in Natura 2000 areas. Protected areas are expected to retain climatic suitability for species better than unprotected areas (P?相似文献   

5.
Setting priorities in biodiversity conservation requires that explicit, efficient and appropriate methods are developed and made available to conservation managers. The principle of complementarity is fundamental to the most efficient of these methods. Given a goal of only a single representation of each taxon, complementarity analysis of data sets of owls, hawkmoths and tiger beetles in Thailand yields near-minimum sets of 6, 14 and 34 areas, respectively. The consensus of these sets comprises 48 areas. However, when the data are combined into a single data set, complementarity analysis gives a more efficient solution of 46 areas. Over 90% of the owls, hawkmoths and tiger beetles are already represented as a minimum of one population within the current protected areas network of Thailand. However, an additional 18 areas are still required for complete representation. Several of these additional areas are discussed and their potential contribution to biodiversity conservation in Thailand examined. Khao Pok Yo and Doi Pa Hom Pok are noted as being of particular importance. The case of Sanpatong emphasizes the need to remain aware of the biology and ecology of the species under study.  相似文献   

6.
Humans and non-human primates have several motor areas. Exactly how many is a matter of current debate. A proper parcellation of motor areas must be based on correlated structural and functional differences. Recent studies indicate that the primary motor cortex may be, in reality, two areas (4a and 4p). Similarly, there are undoubtedly two or more cingulate motor areas and perhaps two supplementary motor areas. The homologies between human and monkey brains are striking in some cases, making monkey models of human motor cortices attractive. The doctrine of a strict ‘homuncular’ somatotopical organization of motor areas will have to be abandoned. The engagement of motor areas in different types of voluntary seems merely a matter of degree of activation rather than exclusive specific contributions.  相似文献   

7.
长江经济带自然保护地边界重叠关系及整合对策分析   总被引:2,自引:0,他引:2  
靳川平  刘晓曼  王雪峰  孙阳阳  付卓  王超  候静 《生态学报》2020,40(20):7323-7334
我国自然保护地类型多样,级别成体系,但由于我国自然保护地一直存在多头管理、权限不清等原因,导致边界混乱、重叠严重。对我国自然保护地空间分布和重叠情况进行梳理是构建以国家公园为主体的自然保护地体系的重要基础,能为我国新型自然保护地的科学选址和优化整合提供有效依据。长江经济带作为我国生态、生活、生产均十分重要的区域,其生态保护具有重要的屏障作用。收集了长江经济带11省份建设开展较成熟的6类自然保护地矢量边界2383个,通过构建重叠关系模型,深入分析了不同类型自然保护地间的边界重叠关系,并针对重叠情况提出系统化对策,结果表明:(1)保护地之间具有重叠关系的数量达1296个,占已获取保护地边界总数的54.4%;重叠部分面积达29728.4 km2,占已获取自然保护地总面积的11.4%;总体呈现为西部重叠面积大、数量多,中部重叠数量多,东部重叠面积小的特点。(2)从重叠区域看,有一次重叠区域的保护地有1138组,有两次重叠区域的有249组,有三次重叠区域的有17组,无四次及以上重叠区域。(3)从重叠关系看,与其他5个及以上保护地有重叠的保护地有56个。(4)通过对重叠区域和关系的分析与政策研究,提出针对不同重叠特性的整合对策,包括勘界调整、合并和类型整合等,并将重叠热点区域提取,以期为自然保护地整合和国家公园建设提供数据支撑,为当前中国自然保护地体系改革的紧迫需求提供参考。  相似文献   

8.
重要生态功能区是指在保持流域、区域生态平衡,防止和减轻自然灾害,确保国家和地区生态安全方面具有重要作用的区域。我国重要生态功能区生态破坏形势十分严峻,严重阻碍了区域社会经济的可持续发展。为此,国家非常重视重要生态功能区的环境保护和生态建设,提出通过建立生态补偿机制,加强对重要生态功能区的保护。重要生态功能区的主导生态功能不仅是保护的主要对象,而且通常还是区外受益区经济利益的关切点,以主导生态功能价值作为生态补偿标准的参考依据,更具有现实性和可操作性。本文以若尔盖重要生态功能区为例进行了研究,对主导生态功能进行了分析和价值评价,从理论核算价值上,提出了若尔盖重要生态功能区生态补偿的参考标准。  相似文献   

9.
The establishment and maintenance of a system of protected areas is central to regional and global strategies for the conservation of biodiversity. The current global trend towards human population growth and widespread environmental degradation means that such areas are becoming increasingly isolated, fragmented habitat islands. In regions in which this process is well advanced, a high proportion of species are thus predicted to have become restricted to protected areas. Here, using uniquely detailed datasets for Britain, a region with close to the global level of percentage coverage by statutory protected areas, we determine the extent of restriction of species of conservation concern to these areas. On the basis of currently known distributions, more than a half of such species are highly dependent on protected areas for their continued persistence, occurring either entirely or largely within their bounds. Such coverage is of particular importance for those species with narrower distributions, and therefore, under the greatest threats, underlining the vital importance of adequately resourcing, maintaining, and developing protected areas to prevent these species from being lost.  相似文献   

10.
It has been empirically established that the cerebral cortical areas defined by Brodmann one hundred years ago solely on the basis of cellular organization are closely correlated to their function, such as sensation, association, and motion. Cytoarchitectonically distinct cortical areas have different densities and types of neurons. Thus, signaling patterns may also vary among cytoarchitectonically unique cortical areas. To examine how neuronal signaling patterns are related to innate cortical functions, we detected intrinsic features of cortical firing by devising a metric that efficiently isolates non-Poisson irregular characteristics, independent of spike rate fluctuations that are caused extrinsically by ever-changing behavioral conditions. Using the new metric, we analyzed spike trains from over 1,000 neurons in 15 cortical areas sampled by eight independent neurophysiological laboratories. Analysis of firing-pattern dissimilarities across cortical areas revealed a gradient of firing regularity that corresponded closely to the functional category of the cortical area; neuronal spiking patterns are regular in motor areas, random in the visual areas, and bursty in the prefrontal area. Thus, signaling patterns may play an important role in function-specific cerebral cortical computation.  相似文献   

11.
三峡库区生态系统服务功能重要性评价   总被引:14,自引:10,他引:14  
在RS与GIS技术支持下,选择研究区比较重要的生物多样性保护、土壤保持、水源涵养和营养物质保持四个生态系统服务功能,建立生态系统服务功能重要性评价模型与方法,对三峡库区重庆段生态系统服务功能进行综合研究,定量揭示了研究区生态系统服务功能重要性程度及其空间分布规律.结果表明:(1)生物多样性保护高度重要以上地区的面积比达到了15%以上;极重要地区主要呈斑块状分布在东北部、中部和东南部.(2)土壤保持极重要区占据绝对优势地位,面积比为68.80%;土壤保持极重要区主要分布在万州及其东北部地区.(3)水源涵养一般重要区面积最大,其次为极重要地区;极重要区沿江河呈带状分布,高度重要区主要分布在极重要区两侧沿江河呈环带状分布.(4)营养物质保持一般重要区面积最大;其次是极重要区;极重要区基本呈条带形分布在植被覆盖较好的山脉及江河两侧.(5)生态系统服务功能极重要和高度重要区的面积占到了研究区总面积的近50%;极重要区基本沿主要江河两侧第一层分水岭和西部平行岭谷区的山脊呈条带形分布;高度重要区基本分布在极重要区两侧层环带形分布,少部分零散分布.  相似文献   

12.
E A Grove  T B Kirkwood  J Price 《Neuron》1992,8(2):217-229
We have tested the hypothesis that cell lineage restriction boundaries define the borders between cytoarchitectonic areas in the cerebral cortex. Clonally related cells were identified using a retroviral marking technique, and the dispersion of neuronal clones was examined with respect to the transitions between cortical areas. We chose to study the hippocampal formation because we found that clones of hippocampal neurons, unlike those in neocortex, are compact and readily identifiable in the adult and that transitions between areas in the hippocampus are sharp relative to the spread of a typical clone. We conclude, contrary to the hypothesis, that clones of neurons transgress the boundaries between areas in the hippocampal formation, that border-crossing clones are observed as frequently as would be expected if clones spread freely over the hippocampus with no constraint imposed by area borders, and that different types of pyramidal neurons, characteristic of different areas, may appear to a single clone. different areas, may appear in a single clone.  相似文献   

13.
Areas of endemism are essential first hypotheses in investigating historical biogeography, but there is a surprising paucity of such hypotheses for the Nearctic region. Miridae, the plant bugs, are an excellent taxon to study in this context, because this group combines high species diversity, often small distribution ranges, a history of modern taxonomic revisions, and comprehensive electronic data capture and data cleaning that have resulted in an exceptionally error‐free geospatial data set. Many Miridae are phytophagous and feed on only one or a small number of host plant species. The programs ndm/vndm are here used on plant bug and plant data sets to address two main objectives: (i) identify areas of endemism for plant bugs based on parameters used in a recent study that focused on Nearctic mammals; and (ii) discuss hypotheses on areas of endemism based on plant bug distributions in the context of areas identified by their host plant species. Given the narrow distribution ranges of many species of Miridae, the analytical results allow for tests of the prediction that areas of endemism for Miridae are smaller and more numerous, especially in the Western Nearctic, than are those of their host plants. Analyses of the default plant bug data set resulted in 45 areas of endemism, 35 of them north of Mexico and many located in the Western Nearctic; areas in the Nearctic are more numerous and smaller than those identified by mammals. The host plant data set resulted in ten areas of endemism, and even though the size range of areas is similar between the Miridae and plant data sets, the average area size is smaller in the Miridae data set. These results allow for the conclusion that the Miridae indeed present a valuable model system to investigate areas of endemism in the Nearctic.  相似文献   

14.
Human population migration is a common phenomenon in developing countries. Four categories of migration—endemic to nonendemic areas, rural to urban areas, non-MDA areas to areas that achieved lymphatic filariasis (LF) control/elimination, and across borders—are relevant to LF elimination efforts. In many situations, migrants from endemic areas may not be able to establish active transmission foci and cause infection in local people in known nonendemic areas or countries. Urban areas are at risk of a steady inflow of LF-infected people from rural areas, necessitating prolonged intervention measures or leading to a prolonged “residual microfilaraemia phase.” Migration-facilitated reestablishment of transmission in areas that achieved significant control or elimination of LF appears to be difficult, but such risk can not be excluded, particularly in areas with efficient vector-parasite combination. Transborder migration poses significant problems in some countries. Listing of destinations, in endemic and nonendemic regions/countries, and formulation of guidelines for monitoring the settlements and the infection status of migrants can strengthen the LF elimination efforts.  相似文献   

15.
Chen LM  Friedman RM  Roe AW 《生理学报》2008,60(5):664-668
While the activation of primary somatosensory (SI) cortex during pain perception is consistently reported in functional imaging studies on normal subjects and chronic pain patients, the specific roles of SI, particularly the subregions within SI, in the processing of sensory aspects of pain are still largely unknown. Using optical imaging of intrinsic signal (OIS) and single unit electrophysiology, we studied cortical activation patterns within SI cortex (among Brodmann areas 3a, 3b and 1) and signal amplitude changes to various intensities of non-nociceptive, thermal nociceptive and mechanical nociceptive stimulation of individual distal finerpads in anesthetized squirrel monkeys. We have demonstrated that areas 3a and 1 are preferentially involved in the processing of nociceptive information while areas 3b and 1 are preferentially activated in the processing of non-nociceptive (touch) information. Nociceptive activations of individual fingerpad were organized topographically suggesting that nociceptive topographic map exits in areas 3a and 1. Signal amplitude was enhanced to increasing intensity of mechanical nociceptive stimuli in areas 3a, 3b and 1. Within area 1, nociceptive response co-localizes with the non-nociceptive response. Therefore, we hypothesize that nocicepitve information is area-specifically represented within SI cortex, in which nociceptive inputs are preferentially represented in areas 3a and 1 while non-nociceptive inputs are preferentially represented in areas 3b and 1.  相似文献   

16.
Protected areas are considered as an essential strategy to halt the decline of biodiversity. Ecological representation in protected areas is crucial for assessment on the progress toward conservation targets. Although China has established a large number of protected areas since the 1950s, ecological representation of protected areas is poorly understood. Here, we performed the complementarity analysis to evaluate ecological representation of protected areas in China. We used a database of the geographical distribution for 10,396 woody plant species, 2,305 fern species, 406 amphibian species, 460 reptile species, 1,364 bird species, and 590 mammal species from 2,376 counties across China. We identified complementary sets of counties for all species or threatened species of plant and vertebrate species using a complementarity algorithm. We evaluated ecological representation of 3,627 protected areas and discerned conservation gaps by comparing the distribution of protected areas with complementary sets. The results show that the spatially representative and complementary sites for biodiversity are poorly covered, and a fairly large proportion of protected areas is not designed to efficiently represent biodiversity at the national scale. Our methodology can serve as a generic framework for assessment on ecological representation of protected areas at the national scale.  相似文献   

17.
Reestablishing a sound environment in rural areas has become one of the most important environmental issues in Japan, not only in rural policy but also in national land policy. Physically speaking, regeneration of natural ecosystems, reestablishment of sound material flows, and the design of rural landscapes are important areas of research and practice. Another important issue in the management of rural areas, particularly in the mountainous areas that cover 61% of the country, is the preparation of the landscape for urban dwellers. This paper considers methods for improving rural environments. The modeling of ideal eco-villages with sound natural environment, low input and sustainable material flow, and maintenance of villages through urban and rural interaction is considered. Three different types of typical eco-village models are designed in urban fringe areas, in typical rural areas and in remote mountainous areas. Further, a case-study for the search of reality in adopting such models is surveyed in Chosei-gun, Chiba prefecture as a case of an eco-village in a typical rural areas.  相似文献   

18.
There are a considerable number of maritime areas where no boundary exists, or where a boundary is delimited only in part. This article deals with the issue of submarine telecommunication cables, which are sometimes placed on the seabed or buried in the subsoil of areas that are claimed by multiple states, and identifies specific issues that arise in the context of areas of overlapping claims.  相似文献   

19.
Protected areas for the 21st century: working to provide benefits to society   总被引:10,自引:0,他引:10  
Since the first national park was created at Yellowstone in the USA in 1872, over 8500 protected areas have been established worldwide. Virtually all countries have seen the wisdom of protecting areas of outstanding importance to society, and such sites now cover over 5% of Earth's land surface. However, many of these protected areas exist only on paper, not on the ground. Most are suffering from a combination of threats, including pollution, over-exploitation, encroachment, poaching, and many others. In a period of growing demands on resources and shrinking government budgets, new approaches are required to ensure that protected areas can continue to make their contributions to society. First and foremost, protected areas must be designed and managed in order to provide tangible and intangible benefits to society. This will involve integrating protected areas into larger planning and management frameworks, linking protected areas to biodiversity and climate change, promoting greater financial support for protected areas, and expanding international cooperation in the finance, development and management of protected areas.  相似文献   

20.
Protected areas have been created worldwide to set apart certain areas from land-use transformation. The biodiversity and ecosystems protected by these areas deliver several ecosystem services. Recently, besides increasing global protected coverage, there has been a growing demand to assess the adequacy of protected areas management. In this study, we assessed how the management of protected areas can deal with ecosystem services taking as example the Doñana and Sierra Nevada protected areas (Spain). For that aim we analyzed the protected area management plans, mapped seven ecosystem services, and assessed how they are affected by protected area zoning and land-use intensity. We found that although provisioning and cultural services are included in the management plans of the protected areas under a different terminology, regulating services are barely addressed. Ecosystem service delivery varies depending on several factors including the protection category of the protected areas (protection intensity), land-use intensity and geomorphological factors, among others. Therefore, we discuss that integrating ecosystem services in protected area management requires dealing with complexity, necessitating the establishment of specific goals for ecosystem service delivery, which include ecosystem service synergies and trade-offs.  相似文献   

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