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1.
In Europe, ponds are an exceptionally numerous and widely distributed landscape feature forming a major part of the continental freshwater resource and contributing significantly to freshwater biodiversity conservation. This has been reflected by a growing scientific concern over the first few years of the twenty-first century and is evidenced by an increasing number of academic publications on pond related topics, particularly those relating to biodiversity. It is essential, however, that this expanding scientific knowledge is widely disseminated to those involved with pond management and is then rapidly translated into action. Inevitably, the task of transferring science to practice remains a significant challenge. As a first step towards meeting this challenge the European Pond Conservation Network (EPCN), at its biennial meeting in 2008 in Valencia (Spain), made this the main theme of the conference together with two special workshops further encouraging exchanges between scientists, practitioners and policy makers. The papers selected for this special issue of Hydrobiologia (from over 120 communications presented) are all from the conference. They represent a diverse collection of themes from across the continent and North Africa and present new and original insights into topics as wide ranging as: pond biodiversity; human disturbance; landscape ecology; ecological assessment and monitoring; practical management measures; ecological restoration; hydrology and climate change; invasive species and threatened species. In all cases, the papers demonstrate an overriding need for the development of a tight link between scientific knowledge and management. Furthermore, scientific advances have to be beneficial for on the ground management and, vitally, have to be disseminated, communicated and implemented into local, national and international policy. As such, national and international networks (such as the EPCN) have a central role to play and have to develop a robust information and communication strategy which will enable the dissemination of best practice materials and advice across the continent and beyond. The work contained in this volume represents a step in the right direction and will help to ensure that ponds remain a characteristic and highly visible feature of the European landscape in the twenty-first century. Guest editors: B. Oertli, R. Céréghino, A. Hull & R. Miracle Pond Conservation: From Science to Practice. 3rd Conference of the European Pond Conservation Network, Valencia, Spain, 14–16 May 2008  相似文献   

2.
The carbon storage and conservation value of old-growth tropical forests is clear, but the value of logged forest is less certain. Here we analyse >100,000 observations of individuals from 11 taxonomic groups and >2,500 species, covering up to 19?years of post-logging regeneration, and quantify the impacts of logging on carbon storage and biodiversity within lowland dipterocarp forests of Sabah, Borneo. We estimate that forests lost ca. 53% of above-ground biomass as a result of logging but despite this high level of degradation, logged forest retained considerable conservation value: floral species richness was higher in logged forest than in primary forest and whilst faunal species richness was typically lower in logged forest, in most cases the difference between habitats was no greater than ca. 10%. Moreover, in most studies >90% of species recorded in primary forest were also present in logged forest, including species of conservation concern. During recovery, logged forest accumulated carbon at five times the rate of natural forest (1.4 and 0.28?Mg?C?ha?1?year?1, respectively). We conclude that allowing the continued regeneration of extensive areas of Borneo??s forest that have already been logged, and are at risk of conversion to other land uses, would provide a significant carbon store that is likely to increase over time. Protecting intact forest is critical for biodiversity conservation and climate change mitigation, but the contribution of logged forest to these twin goals should not be overlooked.  相似文献   

3.
Early successional communities on islands may include specialised aeolian-based pioneer arthropods scavenging on aerial fallout on volcanic lava or ash. Some such species appear to be restricted to such extreme habitats. Persistence of such species may be governed by volcanic activity and their future thus be beyond the control of people. Surveys to determine their presence elsewhere are needed to determine their possible status as refugees in later successional stages, and as a basis for any more informed conservation measures. Insect colonization patterns on Surtsey and Anak Krakatau are briefly reviewed and contrasted to indicate the background to insect community formation on remote islands.  相似文献   

4.
Clinical guidelines, or protocols, have been devised by many different groups, often with differing aims. Some aim to reduce variations in care by using guidelines, while others seek to improve outcomes. Guidelines have long been used in the United States to try to control the behaviour of the medical profession--and the cost of health care. The "effectiveness initiative," run by the Agency for Health Care Policy and Research spawned much activity among other groups, including the American Medical Association and the American College of Physicians. The experience of the Americans in analysing data to gauge effectiveness and then in disseminating good practice may help British moves in this direction. In particular, it is often hard to get guidelines adopted in practice; doctors have to be exposed to the same message in different forms. Also guidelines must not be unrealistic: those devised by senior doctors away from the realities of day to day practice are likely to fail.  相似文献   

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The rationale of promoting onychophorans as target taxa in invertebrate conservation is discussed. Current knowledge relevant to onychophoran conservation is outlined and gaps are identified. The prospects for conserving onychophorans are discussed, and priorities suggested.  相似文献   

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Pleionastraea gen. nov. of the family Lithostrotionidae is described from the Lower Carboniferous Brigantian Stage of northern England. Two species, P. magna P. matura , are referred to it. This astraeoid/thamnasterioid genus is distinguished from Orionastraea by its larger dimensions, but is considered to have followed the same evolutionary trend of a gradual breakdown of the corallite wall.  相似文献   

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Polecat populations show a very low genetic diversity and a high inbreeding coefficient. Furthermore, the estimate of effective population size is alarmingly low. Polecats Mustela putorius populations are structured into scattered breeding sub-units usually made up of one male and two females, according to a polygynous mating system. Because a strict spatio-temporal segregation was observed between males and females, we propose to call individualistic such species. We suggest that the solitary habits of individualistic species may result in or worsen a high inbreeding and exacerbate their conservation issue, a crucial perspective for critically endangered species such as the European mink.  相似文献   

11.
Conservation genetics typically seeks to map the distribution of contemporary genetic variation across space, and to use the resulting genetic parameters to infer any likely short-term evolutionary consequences for rare and endangered species. Recent developments in the study of ancient DNA now enable the extension of genetic variation studies backwards in time and provide a context by which to interpret contemporary levels of genetic variation, in addition to any patterns of genetic change over time. Ancient DNA research can also help to determine past levels of genetic diversity, identify species' boundaries and reveal former ranges among morphologically cryptic taxa. Ancient DNA sequence data for the New Zealand kiwi (Apteryx spp.) are presented and we show that most ancient populations of rowi and tokoeka exhibited private mitochondrial DNA haplotypes. Moreover, we illustrate that the extinction of these populations has led to the loss of considerable genetic variation. We also use ancient DNA methodology to determine past species distributions for brown kiwi and great spotted kiwi whose bones are morphologically indistinguishable.  相似文献   

12.
The relationship between artifact manufacture, use, and discard in the Developed Oldowan is complex. Here we use digital-image-analysis techniques to investigate the intensity of reduction in single-platform cores of the Developed Oldowan of the Okote Member, Koobi Fora Formation. Data suggest that this method provides a more accurate measure of reduction intensity than previous applications of a unifacial-scraper model. Assemblages of single-platform cores excavated from extensive lateral exposures of the Okote Member provide insights into the relationship between raw-material availability and discard patterns. Variation in reduction intensity suggests that tools are not always discarded in patterns that would be predicted by the availability of raw material. Further, it appears that hominin transport decisions involved an assessment of the potential use-life of certain forms. Many aspects of Developed Oldowan technology conform to previously developed models of curated technologies.  相似文献   

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To fully understand human language, an evolved trait that develops in the young without formal instruction, it must be possible to observe language that has not been influenced by instruction. But in modern societies, much of the language that is used, and most of the language that is measured, is confounded by literacy and academic training. This diverts empirical attention from natural habits of speech, causing theorists to miss critical features of linguistic practice. To dramatize this point, I examine data from a special population––the canal boat children of early twentieth century England––whose language developed without academic influence, but was evaluated using instruments designed primarily for academic use. These data, taken together with related research, suggest that formal instruction can convert language from a purely biological trait that was selected, to a talent that was instructed, while altering the users of language themselves. I then review research indicating that formal instruction can also mask or distort inter-sexual differences in the social applications of language, a significant handicap to evolutionary theorizing. I conclude that if biological theories of language are to succeed, they must explain the spontaneous speaking practices of naturally behaving individuals.
John L. LockeEmail:
  相似文献   

15.
With a web of different local actors, often with different perspectives and interests, turning ideas into practice for biodiversity often involves communicating, negotiating, bargaining and, therefore, argumentation. Within this process arguments are selected by actors, to achieve their goals, with varying levels of effectiveness. We examine the use of arguments in UK national biodiversity policies and at the local level from the perspective of those putting forward and receiving arguments. We assess the positive and negative framings within arguments and the effectiveness of arguments. Using interviews and formal documents as sources of data, we analyse nine argumentative interactions from a case study in the Greater Manchester area in the UK. Our findings highlight differences between arguments in national biodiversity policy and those used at the local level. We also show a link between positive framing and salient arguments that were particularly effective. In more polarised, high conflict situations the credibility of the argument, specifically how well it aligned with policy frameworks, strongly influenced its effectiveness. These findings suggest that selecting arguments that identify common ground at the local level contributes to effective outcomes by highlighting areas of mutual benefit. Where this is not possible, a strong policy framework for the conservation of biodiversity is important. A combination of bottom up and top down approaches is most likely to provide effective arguments for biodiversity.  相似文献   

16.

Background  

Being the first noneutherian mammal sequenced, Monodelphis domestica (opossum) offers great potential for enhancing our understanding of the evolutionary processes that take place in mammals. This study focuses on the evolutionary relationships between conservation of noncoding sequences, cis-regulatory elements, and biologic functions of regulated genes in opossum and eight vertebrate species.  相似文献   

17.
In order to evaluate single-occasion sampling in compiling inventories for Odonata, larvae were sampled on 20 occasions from 1987–1990 at a site on Middle Creek, north-eastern Victoria, and adults sought also on each visit to more fully evaluate the diversity of the asemblage, and limitations of depending on a single life stage for this purpose. A total of 18 species (7 Zygoptera, 11 Anisoptera) included 15 species collected as larvae and 16 as adults. Few species were common as larvae, and about half the 2806 specimens identified were Austrogomphus cornutus Watson. Orthetrum caledonicum (Brauer) and Ischnura heterosticta (Burmeister) were also abundant, and these three species were also the most common as adults. The number of species obtained ranged from 2–9 on different occasions, and represent different 'habitat groups' within the local fauna. The Middle Creek odonate fauna appears to be much richer than that of a nearby site on the Kiewa River (12 species), and reasons for this are discussed. Seasonal variation in species representation and relative abundances are noted. Any single sample occasion provided insufficient knowledge of the total assemblage to interpret odonate diversity reliably.  相似文献   

18.
Insects are under-represented in current assessments of biodiversity loss at global and national scales. Butterflies, and a few other insect taxa, have been used as indicators of biodiversity change and as flagships for conservation, especially in temperate zones, but these groups are typically species-poor and may not be representative of insects as a whole. Macro-moths, on the other hand, are an important component of UK biodiversity, in terms of both species richness and ecosystem function. Moth abundance has decreased significantly in the UK and there is rapidly growing interest in the surveillance and monitoring of macro-moths among amateur and professional scientists. The Moths Count project was instigated to raise awareness of moths, increase moth recording and set up a long-term National Moth Recording Scheme for c.900 species of macro-moth in the UK. Since 2006, Moths Count has promoted moths to millions of people, trained and engaged thousands in recording and collated over eight million species distribution records into the National Moth Recording Scheme. These data, though incomplete at present, are already contributing to assessments of biodiversity loss and to conservation initiatives. We present initial results which show that substantial changes are already evident for macro-moths in the UK. The northern range margins of a sample of 12 species have shifted northwards by 194.8 km on average between 1982 and 2009 (7.8 km year?1 over the 25 years between survey mid-points). Provisional distribution trends (not corrected for variation in recording effort) were calculated for 43 species and the results corroborated both positive and negative population-level changes assessed previously.  相似文献   

19.
Exposed riverine sediments (ERS) are an important invertebrate habitat. Ground beetle data from pitfall trap surveys of 165 sites in the catchments of the Rivers Carron, Nith, Spey, Tweed and Eden and from 48 sites in the catchments of the Rivers Blyth, Breamish, Coquet, Glen, Pont, South Tyne, Till, Tweed and Tyne were used to produce ERS habitat classifications in Scotland and northern England respectively. Within each habitat type the quality of sites were assessed using indices based on rarity and fidelity values and using species richness as a measure of diversity. Considerable variation in these indices was seen within and between habitat types, showing potential for their use in assessing site quality and for ranking sites within habitats. The use of standardised invertebrate survey and distribution data, together with species assemblage information, for the conservation of invertebrate habitat types as an alternative to the use of selected indicator species, is discussed.  相似文献   

20.
Tasmanian devil facial tumour disease is an infectious cancer that threatens the largest surviving marsupial carnivore with extinction. After emerging in 1996, it has spread across most of the range of the species, leading to a population decline of more than 60%. This bizarre disease, in which the cancer cells themselves are the infective agent, illustrates some important general principles about disease and conservation biology, including the threat posed by loss of genetic diversity and the potential of pathogens with frequency-dependent transmission to cause extinction.  相似文献   

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