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1.
In a world of massive extinctions where not all taxa can be saved, how ought biologists to decide their preservation priorities? When biologists make recommendations regarding conservation, should their analyses be based on scientific criteria, on public or lay criteria, on economic or some other criteria? As a first step in answering this question, we examine the issue of whether biologists ought to try to save the endangered Florida panther, a well known “glamour” taxon. To evaluate the merits of panther preservation, we examine three important arguments of biologists who are skeptical about the desirability of panther preservation. These arguments are (1) that conservation dollars ought to be spent in more efficient ways than panther preservation; (2) that biologists and conservationists ought to work to preserve species before subspecies; and (3) that biologists and conservationists ought to work to save habitats before species or subspecies. We conclude that, although all three arguments are persuasive, none of them provides convincing grounds for foregoing panther preservation in favor of other, more scientifically significant conservation efforts. Our conclusion is based, in part, on the argument that biologists ought to employ ethical, as well as scientific, rationality in setting conservation priorities and that ethical rationality may provide persuasive grounds for preserving taxa that often are not viewed by biologists as of great importance.  相似文献   

2.
The thematic issue of Biodiversity and Conservation devoted to the biodiversity and conservation of insects and other invertebrates is introduced. The issue comprises 23 original research papers covering diverse habitats from forests to grasslands, ponds and rivers to coasts, and the tropics to boreal regions. Amongst the organisms discussed are ants, bees, beetles, butterflies, crabs, microgastropods, millipedes, spiders, and weevils. Some of the difficulties of conserving the most species-rich groups of eukaryotes, in the face of ignorance as to their identities and positions in ecological processes, are noted and the precautionary principle is seen as a pragmatic and responsible approach.  相似文献   

3.
Conserving biological diversity requires a major effort in conducting survey and inventories, establishing priorities, selecting protected areas, managing resources and monitoring the effects of management. Systematics has an important contribution to make to each of these five major activities. Further, the new Convention on Biological Diversity requires systematics information to support action under virtually all of its substantive conservation and sustainable use articles. It seems apparent that large reference collections contribute directly to development, and development assistance agencies should recognize that investing in maintaining these collections is a legitimate form of development assistance.  相似文献   

4.
Sustainable use of tropical forest systems requires continuous monitoring of biological diversity and ecosystem functions. This can be efficiently done with early warning (short-cycle) indicator groups of non-economical insects, whose population levels and resources are readily measured. Twenty-one groups of insects are evaluated as focal indicator taxa for rapid assessment of changes in Neotropical forest systems. Composite environmental indices for heterogeneity, richness, and natural disturbance are correlated positively with butterfly diversity in 56 Neotropical sites studied over many years. Various components of alpha, beta and gamma-diversity show typical responses to increased disturbance and different land-use regimes. Diversity often increases with disturbance near or below natural levels, but some sensitive species and genes are eliminated at very low levels of interference. Agricultural and silvicultural mosaics with over 30% conversion, including selective logging of three or more large trees per hectare, show shifts in species composition with irreversible loss of many components of the butterfly community, indicating non-sustainable land and resource use and reduction of future options. Monitoring of several insect indicator groups by local residents in a species-rich Brazilian Amazon extractive reserve has helped suggest guidelines for cologically, economically, and socially sustainable zoning and use regimes.  相似文献   

5.
On 12-15 May 2011, a diverse group of students, researchers and practitioners from across Canada and around the world met in Banff, Alberta, to discuss the many facets of biodiversity science at the 6th Annual Meeting of the Canadian Society for Ecology and Evolution.  相似文献   

6.
Biodiversity conservation in China: Legislation, Plans and Measures   总被引:2,自引:0,他引:2  
China is one of the megadiversity countries with over 30,000 species of higher plants and 6347 species of vertebrates, including numerous endemic species and relict species. The vast territory, with its various climates and landforms have formed complex and manifold habitats and rich diversity of ecosystems. China is a signatory country to several international conventions and agreements related to biodiversity and has established a legislation framework for biodiversity conservation. State, interdepartmental, departmental plans related to biodiversity have been made, such as Chinas Agenda 21, the Chinese Country Study on Biological Diversity, the Chinese Biodiversity Conservation Action Plan, the Chinese Environmental Protection Action Plan, and the Guideline for Nature Reserve Development Planning in China (1996–2010). Great efforts have also been made to protect natural resources and the environment, including policies for in situ and ex situ conservation, ecological construction, scientific research, education and training, and international cooperation. However, under the high pressure of population and economy, severe contradiction exists between conservation and the exploitation of biodiversity. This paper describes such achievements and related problems.  相似文献   

7.
Biodiversity and biodiversity conservation in Yunnan, China   总被引:4,自引:3,他引:4  
Yunnan, an inland province at a low latitude and high elevation, lying between 21°09–29°15 N and 97°32–106°12 E in southwestern China, has a vast territory with diversified and unique nature resources. There are more than 18000 high plant species (51.6% of China's total) and 1836 vertebrate species (54.8% of China's total) living in Yunnan on a land area of 39.4 × 104km2, i.e., only 4.1% of China's total. Among 15000 seed plants found in Yunnan there are 151 rare and endangered plant species (42.6% of China's protected plants). Out of 335 China priority protected wild animals, Yunnan has 243 species, accounting for 72.5% of China's total, 15% of which are species endemic to Yunnan. However, Yunnan's biodiversity is faced with the menace of excessive exploitation of resources and changes in environmental conditions caused by the activities of an expanding human population. This paper discusses the background, the composition, and the structure of Yunnan's biodiversity. Its biodiversity fragility and the threatened situation are also discussed. Suggestions and recommendations on the strategy and actions of Yunnan biodiversity conservation and sustainable development are proposed.  相似文献   

8.
The lemurs of Madagascar represent a spectacular example of adaptive radiation among primates. Given the special setting under which they evolved (i.e. long isolation, geographical location, geological relief), they provide excellent models for study in many realms, and at different levels and scales, including diversity. At the same time, they occur in a 'hottest hot spot' region for biodiversity conservation. Although there is no single definition of biodiversity, the most commonly used units to measure biodiversity are species-species richness, species abundance and, for conservation purposes in particular, species endemism. However, what a species actually is or how, precisely, it should be defined are unresolved issues. Many species concepts have been proposed and several have been used in primatology in recent years. Nowadays, one of the more common approaches to measuring diversity, and eventually inferring species status, is to look at genetic diversity as reflected by mitochondrial DNA differences. Not enough attention has been paid, however, to the different levels at which genetic differences may occur. Lemurs provide instructive examples to highlight the questions involved in species recognition and definition. Using lemurs as examples, I will highlight the strengths and limitations of some analytical tools, including phylogeography and cladistic biogeography and, I will, in particular, emphasize the questions arising at the interface of scientific and conservation perceptions, both of which influence decisions in the field of biodiversity preservation.  相似文献   

9.
Summary Three lines of observation demonstrate the role of arthropods in transmission and evolution of viruses. a) Recent outbreaks of viruses from their niches took place and insects have played a major role in propagating the viruses. b) Examination of the list of viral families and their hosts shows that many infect invertebrates (I) and vertebrates (V) or (I) and plants (P) or all kingdoms (VIPs). This notion holds true irrespective of the genome type. At first glance the argument seems to be weak in the case of enveloped and non-enveloped RNA viruses with single-stranded (ss) segmented or non-segmented genomes of positive (+) or negative polarity. Here, there are several families infecting V or P only; no systematic relation to arthropods is found. c) In the non-enveloped plant viruses with ss RNA genomes there is a strong tendency for segmentation and individual packaging of the genome pieces. This is in contrast to ss+ RNA animal viruses and can only be explained by massive transmission by seed or insects or both, because individual packaging necessitates a multihit infection. Comparisons demonstrate relationships in the nonstructural proteins of double-stranded and ss+ RNA viruses irrespective of host range, segmentation, and envelope. Similar conclusions apply for the negative-stranded RNA viruses. Thus, viral supergroups can be created that infect V or P and exploit arthropods for infection or transmission or both. Examples of such relationships and explanations for viral evolution are reviewed and the arthropod orders important for cell culture are given.  相似文献   

10.
In the framework of initiatives, aiming at a better definition of biodiversity in microorganisms and of its role in ecosystem function, the biology of yeasts is revisited with particular emphasis on their ecology and classification. The limited number of different species isolated from, as well as the exceedingly low yeast cell counts in, most natural environments are discussed and possible explanations presented. The impact of the use of molecular taxonomic techniques of classification on the extent of biodiversity within yeasts is also debated, as well as the possible repercussions of more aggressive pre-isolation treatments of samples.  相似文献   

11.
Biodiversity loss, trophic skew and ecosystem functioning   总被引:4,自引:4,他引:4  
Experiments testing biodiversity effects on ecosystem functioning have been criticized on the basis that their random‐assembly designs do not reflect deterministic species loss in nature. Because previous studies, and their critics, have focused primarily on plants, however, it is underappreciated that the most consistent such determinism involves biased extinction of large consumers, skewing trophic structure and substantially changing conclusions about ecosystem impacts that assume changing plant diversity alone. Both demography and anthropogenic threats render large vertebrate consumers more vulnerable to extinction, on average, than plants. Importantly, species loss appears biased toward strong interactors among animals but weak interactors among plants. Accordingly, available evidence suggests that loss of a few predator species often has impacts comparable in magnitude to those stemming from a large reduction in plant diversity. Thus, the dominant impacts of biodiversity change on ecosystem functioning appear to be trophically mediated, with important implications for conservation.  相似文献   

12.
13.
Biodiversity and biogeography of Henderson Island's insects   总被引:1,自引:0,他引:1  
Henderson Island is an example of a raised coral atoll, and as such supports a much more diverse biota than geographically similar low atolls. It is also, due to its remote location, largely undisturbed by the activities of humans. It is therefore unique in the Pacific Ocean, and comparable to Aldabra in the Indian Ocean. Biogeographically it is also interesting as it is amongst the most easterly islands of the Indo-West Pacific region, and has been largely colonized by species dispersing from island to island across the ocean from the west. New and extensive collections of insects were made in 1991. Although not fully identified yet, it is clear that the fauna is depauperate, with only about 180 species known to date. Despite its easterly location almost all species are derived from the west, and much of the fauna is likely to be indigenous. The most diverse orders are the Lepidoptera ( c. 53 spp.), Coleoptera ( c. 38 spp.), Diptera ( c. 37 spp.), Hymenoptera ( c. 21 spp.), Homoptera ( c. 14 spp.) and Heteroptera (4 spp.). Of particular interest are the weevils, Heteroptera and Homoptera which exhibit considerable endemism with perhaps some examples of intra-island radiation. Although depauperate, Henderson supports a much larger insect fauna than that of nearby Ducie Atoll (total known insect fauna =15 spp).  相似文献   

14.
15.
    
  1. The last 3 years have seen a global outbreak of media headlines predicting a global insect apocalypse and a subsequent collapse of natural ecosystems, a so‐called ‘ecological armageddon’ resulting in the demise of human civilisation as we know it. Despite the worrying implications of these papers, all studies on global insect extinction to date clearly reflect the Prestonian shortfall, the general lack of knowledge on the abundance of species and their trends in space and time.
  2. Data currently available concerning global insect abundance trends invariably suffer from phylogenetic, functional, habitat, spatial and temporal bias. Here, we suggest that to follow the real global changes in insect (and all other taxa) communities, biases or shortcomings in data collection must be avoided.
  3. An optimised scheme would maximise phylogenetic, functional, habitat, spatial and temporal coverage with minimum investment. Standardised sampling would provide primary data, on a first step in the form of abundance and biomass. Individuals would then be identified to species level whenever possible, with a morphospecies approach or genetics serving as intermediate steps, complementing or even final steps for non‐described species.
  4. If standardised abundance and ecological data can be readily made available, biodiversity trends can be tracked in real time and allow us to predict and prevent an impending global insect apocalypse.
  相似文献   

16.
Classification of wetlands is extremely problematical, definition of the term wetland being a difficult and controversial starting point. Although considerable effort has gone into the development of national and regional wetland classifications, the only attempt at establishing a global system has been under the auspices of the Ramsar Convention on Wetlands of International Importance. In view of the fact that the Ramsar Convention has 70 Contracting Parties world-wide, it is suggested that the Convention's definition and classification system should be adopted generally for international purposes. Much of the world has been covered by preliminary wetland inventories, but there is an urgent need to extend coverage to those areas not yet included. It is essential that all inventory projects give adequate attention to meeting the real information needs of agencies and individuals which have an impact on the conservation and wise use of wetlands. Attention should also be given to providing for wide dissemination and regular updating of information and establishment of procedures for monitoring ecological change at the sites identified.  相似文献   

17.
Recent morphometric and breeding studies of diatoms show that the present species classification is too coarse and hides significant diversity. Many species are subdivided into phenodemes, which often differ in cell size, shape, stria density and pattern, but may also have different ultrastructural features. In raphid diatoms these can include the form of the raphe endings, details of the pore occlusions, and the structure of the girdle, while chloroplast structure can also vary. The phenodemes can be sympatric or allopatric. In Sellaphora pupula and other species, sympatric phenodemes are reproductively isolated. It is recommended that such demes are recognized as separate species; the total number of diatom species worldwide may thus be at least 2 × 105. Use of a fine-grained classification reveals that many diatom species may be endemics, some restricted to a single lake or catchment, others to wider areas. Environmental impact assessments and conservation strategies must begin to take account of endemism and rarity among microscopic algae and protists.  相似文献   

18.
O. Ciancio 《Plant biosystems》2013,147(2):411-418
Abstract

Classic silviculture and management, with the aim of predicting regeneration rate and producing a constant yield of merchantable wood, have simplified many forests, often transforming natural forests into plantations or coppices. To conserve forest complexity and biodiversity, silviculture and forest management should change the reference paradigm and consider forest ecosystems as complex biological systems characterized by the inherent unpredictability of their trajectories in a continuously changing environment. The new Management Plan for the Vallombrosa Forest (Florence, Italy), a State Nature Reserve and a Natura 2000 Site, is based on this approach. The aim is the gradual evolution of the pure silver fir stands toward mixed stands with a complex structure. Most of the species considered by Natura 2000 depend on an increase of structural diversity at different space and time scales. The management approach proposed by the new plan is coherent with this aim and thus biodiversity conservation is not in conflict with forest management but is, instead, a direct consequence of the systemic approach.  相似文献   

19.
Linke  Simon  Norris  Richard 《Hydrobiologia》2003,500(1-3):203-211
The aim of this study is to create a two-tiered assessment combining restoration and conservation, both needed for biodiversity management. The first tier of this approach assesses the condition of a site using a standard bioassessment method, AUSRIVAS, to determine whether significant loss of biodiversity has occurred because of human activity. The second tier assesses the conservation value of sites that were determined to be unimpacted in the first step against a reference database. This ensures maximum complementarity without having to set a priori target areas. Using the reference database, we assign site-specific and comparable coefficients for both restoration (Observed/Expected taxa with >50% probability of occurrence) and conservation values (O/E taxa with <50%, rare taxa). In a trial on 75 sites on rivers around Sydney, NSW, Australia we were able to identify three regions: (1) an area that may need restoration; (2) an area that had a high conservation value and; (3) a region that was identified as having significant biodiversity loss but with high potential to respond to rehabilitation and become a biodiversity hotspot. These examples highlight the use of the new framework as a comprehensive system for biodiversity assessment.  相似文献   

20.
Xishuangbanna,theregionwhereremainsthevastvirgintropicalforestsinChina,receivesgreatattentionsfromhomeandabroad.Studiesfrom1930’sto1990’sindicatedthatXishuangbannaischaracterizedbyitstransitionalpositionfromtropicstosubtropics.Itsspecialeco-environmentandb…  相似文献   

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