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1.
Extinction risk has been linked to biological and anthropogenic variables. Prediction of extinction risk in valuable fauna may not follow mainstream drivers when species are exploited for international markets. We use results from an International Union for Conservation of Nature Red List assessment of extinction risk in all 377 known species of sea cucumber within the order Aspidochirotida, many of which are exploited worldwide as luxury seafood for Asian markets. Extinction risk was primarily driven by high market value, compounded by accessibility and familiarity (well known) in the marketplace. Extinction risk in marine animals often relates closely to body size and small geographical range but our study shows a clear exception. Conservation must not lose sight of common species, especially those of high value. Greater human population density and poorer economies in the geographical ranges of endangered species illustrate that anthropogenic variables can also predict extinction risks in marine animals. Local-level regulatory measures must prevent opportunistic exploitation of high-value species. Trade agreements, for example CITES, may aid conservation but will depend on international technical support to low-income tropical countries. The high proportion of data deficient species also stresses a need for research on the ecology and population demographics of unglamorous invertebrates.  相似文献   

2.
Mammals contribute to important ecosystem processes and services, but many mammalian species are threatened with extinction. We compare how global patterns in three measures of mammalian diversity—species richness, phylogenetic diversity (PD) and body mass variance (BMV)—would change if all currently threatened species were lost. Given that many facets of species'' ecology and life history scale predictably with body mass, the BMV in a region roughly reflects the diversity of species'' roles within ecosystems and so is a simple proxy for functional diversity (FD). PD is also often considered to be a proxy for FD, but our results suggest that BMV losses within ecoregions would be much more severe than losses of PD or species richness, and that its congruence with the latter two measures is low. Because of the disproportionate loss of large mammals, 65 per cent of ecoregions would lose significantly more BMV than under random extinction, while only 11 per cent would lose significantly more PD. Ecosystem consequences of these selective losses may be profound, especially throughout the tropics, but are not captured by PD. This low surrogacy stresses a need for conservation prioritization based on threatened trait diversity, and for conservation efforts to take an ecosystem perspective.  相似文献   

3.
In a climate marked by expanding scholarship in ethnic and racial studies alongside sweeping changes in universities and the conditions of academic work, we seek to explore the nature of and challenges for critically engaged research, teaching and scholarship on race and racism. In particular, we look at the connection between academic scholarship and political engagement and activity that we are calling race critical public scholarship. We situate the discussion within various recent debates about universities and ‘publics’, and the public orientation and reach of academic work. We set out three frames for these issues: the impact of social movements in establishing race and racism as legitimate topics of academic investigation and setting the agenda for race research; the differing role of academics as public intellectuals and scholar-activists in addressing and engaging with publics and race issues; and the scope and limits of public sociology in addressing the responsibilities and institutionalized power of the academy. We argue that each of these frames offers a partial insight, but that further work is needed based on cases and examples that explore the facility for and challenges of undertaking race critical scholarship.  相似文献   

4.

Background

Soil biota effects are increasingly accepted as an important driver of the abundance and distribution of plants. While biogeographical studies on alien invasive plant species have indicated coevolution with soil biota in their native distribution range, it is unknown whether adaptation to soil biota varies among populations within the native distribution range. The question of local adaptation between plants and their soil biota has important implications for conservation of biodiversity and may justify the use of seed material from local provenances in restoration campaigns.

Methodology/Principal Findings

We studied soil biota effects in ten populations of the steppe grass Stipa capillata from two distinct regions, Europe and Asia. We tested for local adaptation at two different scales, both within (ca. 10–80 km) and between (ca. 3300 km) regions, using a reciprocal inoculation experiment in the greenhouse for nine months. Generally, negative soil biota effects were consistent. However, we did not find evidence for local adaptation: both within and between regions, growth of plants in their ‘home soil’ was not significantly larger relative to that in soil from other, more distant, populations.

Conclusions/Significance

Our study suggests that negative soil biota effects can prevail in different parts of a plant species'' range. Absence of local adaptation points to the possibility of similar rhizosphere biota composition across populations and regions, sufficient gene flow to prevent coevolution, selection in favor of plasticity, or functional redundancy among different soil biota. From the point of view of plant - soil biota interactions, our findings indicate that the current practice of using seeds exclusively from local provenances in ecosystem restoration campaigns may not be justified.  相似文献   

5.
At first sight, the increasing trend of many large mammal populations in EU Member States are the results from successful application of EU environmental legislation. In this perspective a ‘rewilding’ Europe appears as a laudable conservation goal. It has been therefore suggested that the EU model of carnivores-humans coexistence could be of interest to several other regions of the Planet. In the present paper we critically review alleged successes of the EU conservation policies. Our conclusions suggest that some optimistic reports should be taken cautiously. Firstly, one should not lose sight of the heterogeneity of ‘Europe’ and the different histories and socio-ecological situations of the 28 Member States. Furthermore, we doubt whether the positive status of large carnivores in Eastern Europe is attributable exclusively to EU conservation policies. Long time spans necessary for demographic recovery in large carnivores sharply contradict the quite recent entry of these countries into the EU. The EU model is possible owing to the unique socio-economic development that Western Europe experienced after the Second World War. Economic growth, urbanization, rural abandonment and reforestation are the main forces behind the increase of large mammals in some areas of Western Europe. Yet this has been possible only through a considerable input of natural resources from outside EU (food, raw materials, oil, gas etc.). Therefore, although there are examples that could be considered good experiences, we are of the opinion that the EU policies as a general model is unlikely to be exportable world-wide and may have negative consequences for wildlife, even in Eastern Europe.  相似文献   

6.
A cellular logic for G protein-coupled ion channel pathways.   总被引:5,自引:0,他引:5  
A M Brown 《FASEB journal》1991,5(8):2175-2179
A vast array of cellular signal transduction processes arise from combinations of many different types of agonists, receptors, effectors, and coupling molecules such as heterotrimeric G proteins or protein kinases that connect receptors to effectors. Receptors, effectors, G proteins, and kinases are being newly identified at bewildering speeds and in the process it seems that our understanding of how cells respond to specific stimuli may have diminished just as we lose sight of the forest when we are buried in the trees. Evolution would suggest that there may be a logic to the response provoked by a given stimulus and, using our recently acquired knowledge of G protein pathways between receptors and ion channel effectors, I will attempt to decipher what the underlying logic might be.  相似文献   

7.
Recent reviews of the conservation literature indicate that significant biases exist in the published literature regarding the regions, ecosystems and species that have been examined by researchers. Despite the global threat of climatic change, similar biases may be occurring within the sub-discipline of climate-change ecology. Here we hope to foster critical thought and discussion by considering the directions taken by conservation researchers when addressing climate change. To form a quantitative basis for our perspective, we assessed 248 papers from the climate change literature that considered the conservation management of biodiversity and ecosystems. We found that roughly half of the studies considered climate change in isolation from other threatening processes. We also found that the majority of surveyed scientific publications were conducted in the temperate forests of Europe and North America. Regions such as Latin America that are rich in biodiversity but may have low adaptive capacity to climate change were not well represented. We caution that such biases in research effort may be distracting our attention away from vulnerable regions, ecosystems and species. Specifically we suggest that the under-representation of research from regions low in adaptive capacity and rich in biodiversity requires international collaboration by those experienced in climate-change research, with researchers from less wealthy nations who are familiar with local issues, ecosystems and species. Furthermore, we caution that the propensity of ecologists to work in essentially unmodified ecosystems may fundamentally hamper our ability to make useful recommendations in a world that is experiencing significant global change.  相似文献   

8.
The conversion of natural forest to oil palm plantation is a major current threat to the conservation of biodiversity in South East Asia. Most animal taxa decrease in both species richness and abundance on conversion of forest to oil palm, and there is usually a severe loss of forest species. The extent of loss varies significantly across both different taxa and different microhabitats within the oil palm habitat. The principal driver of this loss in diversity is probably the biological and physical simplification of the habitat, but there is little direct evidence for this. The conservation of forest species requires the preservation of large reserves of intact forest, but we must not lose sight of the importance of conserving biodiversity and ecosystem processes within the oil palm habitat itself. We urgently need to carry out research that will establish whether maintaining diversity supports economically and ecologically important processes. There is some evidence that both landscape and local complexity can have positive impacts on biodiversity in the oil palm habitat. By intelligent manipulation of habitat complexity, it could be possible to enhance not only the number of species that can live in oil palm plantations but also their contribution to the healthy functioning of this exceptionally important and widespread landscape.  相似文献   

9.
This article revisits recent debates about the responsibilities of public scholarship. The piece argues that writing in a range of fields has engaged with issues of racism, in particular as racism has been manifested in the ‘war on terror’, but that this discussion has been muted within the sub-field of race and ethnic studies. There is a discussion of the impact of pressures to demonstrate the ‘usefulness’ of research to a wider public and the limits that this can place on the formulation of research. This argument is expanded through consideration of the author's experience of researching and lobbying with community and campaigning groups. The piece goes on to consider the implications of the marketization of higher education for critical scholarship and concludes that there is value in a more ‘private’ sociology that may not be easily accommodated in the marketized university.  相似文献   

10.
Giant pandas (Ailuropoda melanoleuca) are an iconic conservation species, but despite significant research effort, do we understand what they really need? Estimating and mapping suitable habitat play a critical role in conservation planning and policy. But if assumptions about ecological needs are wrong, maps with misidentified suitable habitat will misguide conservation action. Here, we use an information-theoretic approach to analyse the largest, landscape-level dataset on panda habitat use to date, and challenge the prevailing wisdom about panda habitat needs. We show that pandas are associated with old-growth forest more than with any ecological variable other than bamboo. Other factors traditionally used in panda habitat models, such as topographic slope, are less important. We suggest that our findings are disparate from previous research in part because our research was conducted over a larger ecological scale than previous research conducted over more circumscribed areas within individual reserves. Thus, extrapolating from habitat studies on small scales to conservation planning on large scales may entail some risk. As the Chinese government is considering the renewal of its logging ban, it should take heed of the panda''s dependency on old growth.  相似文献   

11.
Global protected area impacts   总被引:3,自引:0,他引:3  
Protected areas (PAs) dominate conservation efforts. They will probably play a role in future climate policies too, as global payments may reward local reductions of loss of natural land cover. We estimate the impact of PAs on natural land cover within each of 147 countries by comparing outcomes inside PAs with outcomes outside. We use 'matching' (or 'apples to apples') for land characteristics to control for the fact that PAs very often are non-randomly distributed across their national landscapes. Protection tends towards land that, if unprotected, is less likely than average to be cleared. For 75 per cent of countries, we find protection does reduce conversion of natural land cover. However, for approximately 80 per cent of countries, our global results also confirm (following smaller-scale studies) that controlling for land characteristics reduces estimated impact by half or more. This shows the importance of controlling for at least a few key land characteristics. Further, we show that impacts vary considerably within a country (i.e. across a landscape): protection achieves less on lands far from roads, far from cities and on steeper slopes. Thus, while planners are, of course, constrained by other conservation priorities and costs, they could target higher impacts to earn more global payments for reduced deforestation.  相似文献   

12.
Glaciation accompanied our human ancestors in Africa throughout the Pleistocene. Regrettably, equatorial glaciers and snow are disappearing rapidly, and we are likely the last generation who will get to know these peculiar places. Despite the permanently harsh conditions of glacier/snow habitats, they support a remarkable diversity of life ranging from bacteria to animals. Numerous papers have been devoted to microbial communities and unique animals on polar glaciers and high mountains, but only two reports relate to glacial biodiversity in equatorial regions, which are destined to melt completely within the next few decades. Equatorial glaciers constitute “cold islands” in tropics, and discovering their diversity might shed light on the biogeography, dispersal, and history of psychrophiles. Thus, an opportunity to protect biota of equatorial glaciers hinges on ex situ conservation. It is timely and crucial that we should investigate the glacial biodiversity of the few remaining equatorial glaciers.  相似文献   

13.
Patches of fire‐sensitive vegetation often occur within fire‐prone tropical savannas, and are indicative of localized areas where fire regimes are less severe. These may act as important fire refugia for fire‐sensitive biota. The fire‐sensitive tree Callitris intratropica occurs in small patches throughout the fire‐prone northern Australian savannas, and is widely seen as an indicator of low‐severity fire regimes and of good ecosystem health. Here, we address the question: to what extent do Callitris patches act as refuges for other fire‐sensitive biota, and therefore play a broader conservation role? We contrast floral and faunal species composition between Callitris patches and surrounding eucalypt savanna, using three case studies. In the first case study, a floristic analysis of 47 Callitris patches across Western Australia's Kimberley region showed that woody species in these patches were overwhelmingly widespread, fire‐tolerant savanna taxa. No species of special conservation concern occurred disproportionately within Callitris patches. Similarly, there was no concentration of fire‐sensitive fauna or flora in five Callitris patches in the East Kimberley. Finally, there was no difference in ant species composition among 12 Callitris patches and surrounding eucalypt savannas in Kakadu National Park, Northern Territory, and there were no fire‐sensitive ant species in Callitris patches. Our three case studies from throughout the northwestern Australia provide no evidence that Callitris patches act as important refuges for fire‐sensitive flora or fauna within fire‐prone eucalypt savannas. This calls into question the notion that Callitris is a strong indicator of general ecosystem health.  相似文献   

14.
The financial cost of biodiversity conservation varies widely around the world and such costs should be considered when identifying countries to best focus conservation investments. Previous global prioritizations have been based on global models for protected area management costs, but this metric may be related to other factors that negatively influence the effectiveness and social impacts of conservation. Here we investigate such relationships and first show that countries with low predicted costs are less politically stable. Local support and capacity can mitigate the impacts of such instability, but we also found that these countries have less civil society involvement in conservation. Therefore, externally funded projects in these countries must rely on government agencies for implementation. This can be problematic, as our analyses show that governments in countries with low predicted costs score poorly on indices of corruption, bureaucratic quality and human rights. Taken together, our results demonstrate that using national-level estimates for protected area management costs to set global conservation priorities is simplistic, as projects in apparently low-cost countries are less likely to succeed and more likely to have negative impacts on people. We identify the need for an improved approach to develop global conservation cost metrics that better capture the true costs of avoiding or overcoming such problems. Critically, conservation scientists must engage with practitioners to better understand and implement context-specific solutions. This approach assumes that measures of conservation costs, like measures of conservation value, are organization specific, and would bring a much-needed focus on reducing the negative impacts of conservation to develop projects that benefit people and biodiversity.  相似文献   

15.
For fourteen years public attention has been focused so sharply on atomic weapons as to lose sight of other, less spectacular but equally significant advances in the art of warfare. In the shadows cast by brilliant research in nuclear physics are hidden startling advances in the field of chemical and biological weapons. These weapons, as now developed, are not only capable of producing mass casualties quite comparable with those of atomic bombs, but they also possess certain advantages which may make them the weapons of choice for an unscrupulous enemy. If war should come, it is the medical profession which will have the sole responsibility for protecting the citizens of California against these weapons, and we can therefore delay no longer in acquainting ourselves with their potentialities and characteristics. In this task, we are working under two serious handicaps. The first is that our classical medical training affords little appreciation of the real danger, and the second is the cloak of secrecy surrounding the entire subject.  相似文献   

16.
For fourteen years public attention has been focused so sharply on atomic weapons as to lose sight of other, less spectacular but equally significant advances in the art of warfare.In the shadows cast by brilliant research in nuclear physics are hidden startling advances in the field of chemical and biological weapons. These weapons, as now developed, are not only capable of producing mass casualties quite comparable with those of atomic bombs, but they also possess certain advantages which may make them the weapons of choice for an unscrupulous enemy.If war should come, it is the medical profession which will have the sole responsibility for protecting the citizens of California against these weapons, and we can therefore delay no longer in acquainting ourselves with their potentialities and characteristics.In this task, we are working under two serious handicaps. The first is that our classical medical training affords little appreciation of the real danger, and the second is the cloak of secrecy surrounding the entire subject.  相似文献   

17.
Although potentially beneficial in terms of raising awareness and conservation funding, tourist visitation of wild primates can have negative impacts on visited groups. Tourism‐generated noise is a relatively understudied facet of ecotourism research, and the effects of tourist‐generated speech on free‐ranging, wild primates has never been explored previously. This study investigates the behavioral responses of 10 groups of pygmy marmosets (Cebuella pygmaea) to human speech. Through the use of an experimental playback study using recorded human speech, we show that pygmy marmosets within the Tamshiyacu‐Tahuayo Reserve, Peru, are significantly less visible, and often move completely out of sight after louder playbacks. Although no consistent differences were found in other behaviors with playback duration and volume, playbacks of human speech tended to increase the amount of time individuals were alert and decrease feeding and resting behaviors. Our results demonstrate that human speech can alter the behavior of visited primates, and identifies a decrease in primate visibility within the increasing volume. As all trials in this study took place near a marmoset group's feeding tree, moving out of sight from the visible study area is a particularly energetically costly behavior, and also has a negative effect on visitor enjoyment as it limits the time that they are able to view the target species. This response was not observed (nor was any other consistent behavior change) in control trials where the marmosets were exposed to human presence but not to speech, suggesting that negative tourist impacts can be reduced by encouraging tourists to refrain from speaking in the presence of visited primate groups.  相似文献   

18.
《Anthrozo?s》2013,26(4):613-619
ABSTRACT

Zoo animals serve an important function in helping educate the public about their conservation needs. Despite this important function, little is understood about how visitors perceive different zoo exhibits and the animals that reside within them. In the present study, the behaviors displayed by two jaguars located at the Woodland Park Zoo were correlated with visitor behaviors and perceptions. Overall, visitors perceived their enjoyment to be lower when a jaguar was out of sight and rated the behavioral welfare of the jaguar to be lower when it was engaged in stereotypic behaviors. In addition, visitors who described a jaguar's behavior as stereotypic were significantly more likely to give lower ratings than those who perceived the jaguar to be active. It is suggested that by understanding how visitors perceive exhibited animals, zoos can address these perceptions in order to create more positive experiences for their visitors.  相似文献   

19.
Understanding the shifts in competitive ability and its driving forces is key to predict the future of plant invasion. Changes in the competition environment and soil biota are two selective forces that impose remarkable influences on competitive ability. By far, evidence of the interactive effects of competition environment and soil biota on competitive ability of invasive species is rare. Here, we investigated their interactive effects using an invasive perennial vine, Mikania micrantha. The competitive performance of seven Mmicrantha populations varying in their conspecific and heterospecific abundance were monitored in a greenhouse experiment, by manipulating soil biota (live and sterilized) and competition conditions (competition‐free, intraspecific, and interspecific competition). Our results showed that with increasing conspecific abundance and decreasing heterospecific abundance, (1) Mmicrantha increased intraspecific competition tolerance and intra‐ vs. interspecific competitive ability but decreased interspecific competition tolerance; (2) Mmicrantha increased tolerance of the negative soil biota effect; and (3) interspecific competition tolerance of Mmicrantha was increasingly suppressed by the presence of soil biota, but intraspecific competition tolerance was less affected. These results highlight the importance of the soil biota effect on the evolution of competitive ability during the invasion process. To better control Mmicrantha invasion, our results imply that introduction of competition‐tolerant native plants that align with conservation priorities may be effective where Mmicrantha populations are long‐established and inferior in inter‐ vs. intraspecific competitive ability, whereas eradication may be effective where populations are newly invaded and fast‐growing.  相似文献   

20.
Both conservation biology and macroecology are synthetic, and macroecological research consistently has informed the theory and practice of biological conservation. Explicit integration of the macroecology of human systems and natural systems has been rare, but can advance the incorporation of social justice, environmental justice and environmental equity into conservation biology and participatory conservation (inclusion in decision‐making of those who are affected by, or can affect, that decision). The basis of this strong link is the focus of macroecology on the relations of a given biota to environmental patterns and processes, and these patterns and processes can affect humans differentially. Macroecological integration of social justice and conservation generally requires spatial and temporal representation of all variables at resolutions and extents that allow meaningful analyses. This requirement may facilitate clarity about social metrics and norms. To illustrate, we examine applications of macroecology to analysis of the effects of climate change on social justice and biological conservation; relations among climate, violence among humans and conservation; and the response of the spread of disease to social and ecological factors. We believe that macroecology is a means of providing transparent inferences that can inform conservation, health and social policies.  相似文献   

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