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1.
First developed in the USA in the early 1970s, ‘wetland mitigation banks’ provide a framework for conservation activities that are designed to offset residual, unavoidable damage to the natural environment caused by development activities. The concept is now a worldwide phenomenon. In this paper I consider the level of success of wetland mitigation banks in the USA for biodiversity conservation with a view to informing ‘best practice’ in Australia. I conclude that although the concept has merit, even in the USA where the processes have been evolving for over 30 years, the outcomes frequently fall short of the target of a ‘like for like’ swap of habitat. While the outcome for wetland mitigation may not be an ‘unmitigated disaster’ it is, at best, apparently only modestly successful.  相似文献   

2.
Conflicts between the conservation of biodiversity and other human activities occur in all habitats and can impact severely upon socio-economic and biological parameters. In a changing environment, with increasing pressure on ecosystem goods and services and increasing urgency for biodiversity conservation, these conflicts are likely to increase in importance and magnitude and negatively affect biodiversity and human well-being. It is essential, however, to better understand what is meant by ‘biodiversity conflicts’ in order to develop ways to manage these effectively. In view of the complexity of the social and ecological contexts of conflicts, this paper explores ‘biodiversity impacts’ linked to agricultural, forestry and other sectoral activities in the UK. The paper then describes the transition from ‘biodiversity impacts’ to ‘biodiversity conflicts’, illustrating this concept with specific examples. While generalisations relating to conflict management are made difficult by their unique contextual settings, this paper suggests approaches for their management, based on the experiences of scientists who have been involved in managing conflicts. We consider the role of science and scientists; trust and dialogue; and temporal and spatial scales in biodiversity conflicts and highlight the combined role they play in successful biodiversity conflict management. Recommendations are also made for future research on biodiversity conflicts in a changing environment.  相似文献   

3.
Biodiversity indices are frequently used to provide a numerical value of the diversity of species within an ecological community. To study fungal biodiversity in the air, a 7-day recording Hirst-type spore trap was used. The daily concentration of 124 taxa was recorded in an Italian vineyard. The predominant fungi were: Cladosporium spp., unknown 3-septate fusiform spore, and Alternaria spp. Shannon’s and Simpson’s biodiversity indices and evenness were calculated first for air spora. Meteorological circumstances affected the biodiversity; positive correlations were found between Simpson’s biodiversity index and precipitation, but no significant correlations were found with Shannon’s diversity index and evenness. To predict Simpson’s index for airborne fungi, regression analysis was performed. It was shown that the best estimator, sun hours, negatively affected the index. The biodiversity of the dominant species was low on dry days, since Cladosporium alone had much higher abundance on such days than other species.  相似文献   

4.
In 2007 an unusual crayfish found in food markets in the capital of Madagascar was preliminarily identified as Procambarus ‘Marmorkrebs’: a new world taxa and the only decapod known to reproduce by parthenogenesis. We present information on the identity, distribution and ecology of this recent invader and attempt to evaluate the threat it poses to Madagascar’s biodiversity and to livelihoods. The species appears to be currently limited to the area close to Antananarivo, but is being sold alive on major transport routes. We present molecular evidence of its taxonomic relationships and confirm that the Procambarus present in Madagascar is indeed the parthenogenic taxa. We investigate its reproductive ecology and find Procambarus ‘Marmorkrebs’ to have an extremely high fecundity; more than six times that of the native crayfish Astacoides. The limited evidence we have suggests that this species poses a serious threat to freshwater biodiversity and that it is likely to damage human livelihoods (through its impact on fishing and possibly rice agriculture). More research is urgently needed but in the meantime action is needed to reduce the rate of spread before it is too late.  相似文献   

5.
Coral reefs in shallow-water environments (<30 m) are in decline due to local and global anthropogenic stresses. This has led to renewed interest in the ‘deep reef refugia’ hypothesis (DRRH), which stipulates that deep reef areas (1) are protected or dampened from disturbances that affect shallow reef areas and (2) can provide a viable reproductive source for shallow reef areas following disturbance. Using the Caribbean as an example, the assumptions of this hypothesis were explored by reviewing the literature for scleractinian corals—the reef framework builders on tropical reefs. Although there is evidence to support that deep reefs (>30 m) can escape the direct effects of storm-induced waves and thermal bleaching events, deep reefs are certainly not immune to disturbance. Additionally, the potential of deep reefs to provide propagules for shallow reef areas seems limited to ‘depth-generalist’ coral species, which constitute only ~25% of the total coral biodiversity. Larval connectivity between shallow and deep populations of these species may be further limited due to specific life history traits (e.g., brooding reproductive strategy and vertical symbiont acquisition mode). This review exposes how little is known about deep reefs and coral reproduction over depth. Hence, a series of urgent research priorities are proposed to determine the extent to which deep reefs may act as a refuge in the face of global reef decline.  相似文献   

6.
Among the conservation initiatives, biodiversity banking is a strategic new concept that calls for advocacy by the researchers, conservationists, policy planners and business corporate houses to enhance the conservational behaviour of the stakeholders. The concept has dual benefits of restoration of livelihood support systems and conservation of biodiversity that provides ecological services and economic benefits to civil society. Currently, lack of defined guidelines with robust valuation and incentive mechanism for biodiversity banking has resulted in ‘business as usual’ situation especially in developing and under developed countries. There is need for re-defining the country level biodiversity banking guidelines for the effective private-government-stakeholder participation. Furthermore, the mechanism must consider using robust scientific database of inter-disciplinary nature and suitably adopt the modalities of successful case studies to overcome the flaws/risks. Biodiversity banking is a realizable concept in developing and resource poor countries as additional livelihood support system through the market of accrued ecosystem services linked to conservation behaviour of stakeholders.  相似文献   

7.
There is a widespread belief that we are experiencing a mass extinction event similar in severity to previous mass extinction events in the last 600 million years where up to 95% of species disappeared. This paper reviews evidence for current extinctions and different methods of assessing extinction rates including species–area relationships and loss of tropical forests, changing threat status of species, co-extinction rates and modelling the impact of climate change. For 30 years some have suggested that extinctions through tropical forest loss are occurring at a rate of up to 100 species a day and yet less than 1,200 extinctions have been recorded in the last 400 years. Reasons for low number of identified global extinctions are suggested here and include success in protecting many endangered species, poor monitoring of most of the rest of species and their level of threat, extinction debt where forests have been lost but species still survive, that regrowth forests may be important in retaining ‘old growth’ species, fewer co-extinctions of species than expected, and large differences in the vulnerability of different taxa to extinction threats. More recently, others have suggested similar rates of extinction to earlier estimates but with the key cause of extinction being climate change, and in particular rising temperatures, rather than deforestation alone. Here I suggest that climate change, rather than deforestation is likely to bring about such high levels of extinction since the impacts of climate change are local to global and that climate change is acting synergistically with a range of other threats to biodiversity including deforestation.  相似文献   

8.
In October, nations of the world will begin negotiations for the post‐2020 Global Biodiversity Framework under the Convention on Biological Diversity. An influential ambition is “bending the curve of biodiversity loss,” which aims to reverse the decline of global biodiversity indicators. A second relevant, yet less prominent, milestone is the 20th anniversary of the publication of The Unified Neutral Theory of Biodiversity and Biogeography. Here, I apply neutral theory to show how global biodiversity indicators for population size (Living Planet Index) and extinction threat (Red List Index) decline under neutral ecological drift. This demonstrates that declining indicators are not solely caused by deterministic species‐specific or geographical patterns of biodiversity loss. Instead, indicators are sensitive to nondirectional stochasticity. Thus, “bending the curve” could be assessed relative to a counterfactual based on neutral theory, rather than static baselines. If used correctly, the 20‐year legacy of neutral theory can be extended to make a valuable contribution to the post‐2020 Global Biodiversity Framework.  相似文献   

9.
The IUCN Red List classification scheme has, for many years, aided the prioritisation of conservation action by identifying taxa most at risk of extinction. This is a study of the accumulation of knowledge concerning extinction risk in gamebirds over the last 25 years (the Red Lists published in 1981, 1988, 1994, 2000 and 2004). The change from the rather subjective assessment criteria of the 1980s to the more quantitative scheme of 1994 was marked by a sharp increase in the proportion of species classed as threatened. Between 1994 and 2000, 17% of threatened species moved threat category (21 upgraded and 28 downgraded) while between 2000 and 2004 just 7% of species shifted category. The main threat criteria (those associated with ‘declining population’, ‘small range’ and ‘small population’) were used in similar proportions in 1994 and 2000, suggesting no real change in the ways that classifications are arrived at. Decision tree analysis showed that species moving between threat categories between 1994 and 2004 tended to be polytypic and have large global ranges, suggesting that such species are amongst those most difficult to classify. Considering actual direction of change between 1994 and 2004, geographic region and taxonomic group were important, with pheasants, and partridges and their allies (species of the Palearctic and Oriental regions), tending to be downgraded, and the grouse, megapodes and cracids of the New World and Australasia tending to be upgraded. While there are now few movements in threat category between assessments, we caution that this certainly does not mean that we have accumulated adequate knowledge to properly support the classifications for most species.  相似文献   

10.
We evaluated the efficiency of callus induction and plantlet regeneration from hypocotyl explants of broccoli (Brassica oleracea var. italica). The cultivars were ‘Marathon’, ‘Greenbelt’, and ‘Shogun’. Transformation success was not affected by the presence of tobacco feeder-cell layers on the culture media. The frequency of shoot regeneration was greater from 10-d-old hypocotyls than from 14-d-old hypocotyls. Both ‘Marathon’ and ‘Greenbelt’ had higher potentials for tissue regeneration than did ‘Shogun’. We found that for transformation selection, the optimum concentration was either 50 mg/L kanamycin or 100 mg/L genetkin.  相似文献   

11.
Biodiversity monitoring in developing countries has long been haunted by problems with sustaining monitoring programs, especially after funding stops. Current programs are developed to fulfill strict scientific demands, which often results in high priced programs, with little local participation and attention. Thus, to enhance sustainability of the biodiversity programs, there is a great need to reconcile scientific rigor with local involvement. In this paper, we analyze the cost-effectiveness and usefulness of a standard and a participatory monitoring method, in their ability to monitor biodiversity, while rising local participation. As a standard method we used a forest characteristic with tree basal area and Shannon index as proxy for biodiversity. Interviews were used as a participatory approach, with hunters’ catch-effort as proxy. The analysis showed that the interviews reached a better precision with fewer work hours spent and at the same time involved local populations and stake holders. As a tradeoff, the interviews lacked the scientific rigor from forest characteristic. In order to sustain monitoring programs, we conclude that conservation biologists needs to compromise between scientific rigor and public participation.  相似文献   

12.
Science-based approaches to support the conservation of marine biodiversity have been developed in recent years. They include measures of ‘rarity’, ‘diversity’, ‘importance’, biological indicators of water ‘quality’ and measures of ‘sensitivity’. Identifying the sensitivity of species and biotopes, the main topic of this contribution, relies on accessing and interpreting available scientific data in a structured way and then making use of information technology to disseminate suitably presented information to decision makers. The Marine Life Information Network (MarLIN) has achieved that research for a range of environmentally critical species and biotopes over the past four years and has published the reviews on the MarLIN Web site (www.marlin.ac.uk). Now, by linking the sensitivity database and databases of survey information, sensitivity mapping approaches using GIS are being developed. The methods used to assess sensitivity are described and the approach is advocated for wider application in Europe.  相似文献   

13.
We performed a bibliometric analysis of published biodiversity research for the period of 1900–2009, based on the Science Citation Index (SCI) database. Our analysis reveals the authorial, institutional, spatiotemporal, and categorical patterns in biodiversity research and provides an alternative demonstration of research advancements, which may serve as a potential guide for future research. The growth of article outputs has exploded since the 1990s, along with an increasing collaboration index, references, and citations. Ecology, environmental sciences, biodiversity conservations, and plant science were most frequently used subject categories in biodiversity studies, and Biological Conservation, Journal of Soil and Water Conservation, Conservation Biology and Biodiversity and Conservation were most active journals in this field. The United States was the largest contributor in global biodiversity research, as the U.S. produced the most single-country and collaborative articles, had the greatest number of top research institutions, and had a central position in collaboration networks. We perceived an increasing number of both internationally collaborative and inter-institutionally collaborative articles, with the latter form of collaboration being more prevalent than the former. A keyword analysis found several interesting terminology preferences, confirmed conservation’s central position as a topic in biodiversity research, revealed the adoption of advanced technologies, and demonstrated keen interest in both the patterns and underlying processes of ecosystems. Our study reveals patterns in scientific outputs and academic collaborations and serves as an alternative and innovative way of revealing global research trends in biodiversity.  相似文献   

14.
The high biodiversity observed in coastal lagoons can often be related to a very high degree of environmental heterogeneity (β-biodiversity). In this article, I describe many physical factors that contribute to create environmental heterogeneity and different habitats within the Bassin d’Arcachon, a mesotidal lagoon in S.W. France. The microbial biodiversity has been studied in this coastal lagoon by culture-dependent and culture-independent techniques. The sediments of the meadows of the seagrass Zostera noltii have received a specific focus. During the last 15 years, several novel bacterial species have been isolated from these sediments and obtained in culture. Among these, five different species have been fully described as novel species according the Bacteriological Code and two of them represent also the type strain for a novel genus. The bacterial biodiversity has also been studied by molecular ecology techniques. An early study was focused on water column bacteria and a comparison has been made with the same community from the more eutrophic Prévost lagoon (France, Mediterranean coast). A clone library was also constructed for 16-S rRNA genes isolated and amplified from the 1–2 cm depth layer of the Z. noltii sediment. These studies showed a high degree of biodiversity and the importance of sulfate-reducing bacteria in the sediment, pointing to species that have not been obtained in culture. Collectively, these data show that there is still a large discrepancy between culture-dependent and culture-independent prokaryotic biodiversity. It is important to link the functional biogeochemical approach with the biodiversity approach. For the Bassin d’Arcachon studies, the biogeochemical approach has successfully nurtured the biodiversity studies, while the reverse has not yet been the case as the biogeochemical studies have lumped prokaryotes in functional groups. Guest editors: A. Razinkovas, Z. R. Gasiūnaitė, J. M. Zaldivar & P. Viaroli European Lagoons and their Watersheds: Function and Biodiversity  相似文献   

15.
16.
The damselflyMnais pruinosa costalis (Odonata: Calopterygidae) is unusual in that males are dimorphic, existing as clear-winged non-territorial ‘sneaks’ and orange-winged territorial ‘fighters’. Here we report the results of population census data and behavioural observations in the field and laboratory, and present estimates of emergence period, reproductive period, total lifespan, and reproductive success of each morph. Clear-winged males are smaller and have lower daily reproductive success than orange-winged males, but live for longer in the field and laboratory. We accounted for the difference in the ‘operational reproductive life’ of the two morphs and estimated lifetime reproductive success: there was no difference between clear-winged and orange-winged males. We discuss possible mechanisms for the maintenance of the two forms.  相似文献   

17.
We describe an approach to multi-species recovery planning and bio-regional biodiversity assessment that uses trait-based plant functional groups as the basis for developing threat/risk assessments for rare, threatened and ‘of concern’ species. Multi-variate methods were used to extract and test emergent groups, and additional information fields related to species life history and distributional data were added to develop a species-level information assessment matrix in spreadsheet format. Relating emergent trait-based plant functional groups to habitat was found to be the most informative approach for the subsequent development of management recommendations and landscape scale threat/risk assessment to inform recovery planning. Examples on the use of the identified groups in a management context are provided. These include higher and lower resource and data availability scenarios, and the role of selected traits in adding to or ameliorating threats and risk of extinction.  相似文献   

18.
The term ‘asylum’ has a dual connotation that generates opposing but related forms of intervention: providing sanctuary and protection vs. imposing confinement and quarantine. The proliferation of “neomodern insecurity”—intrastate violence and the specter of transnational terrorism, arising within many postcolonial, postauthoritarian and postsocialist states—generates intervention practices that reflect the dual connotations of asylum. In fragile states like Haiti, national insecurity (ensekirite) often results in the flight of traumatized populations across and within national borders. For these individuals, ‘asylum’ connotes the attainment of political recognition and inclusion outside Haiti’s space of ensekirite. Ironically, these vulnerable persons may be viewed as threats to the nations they seek to enter. In so-called secure states like the United States, the threat of insecurity often engenders interventions to contain, manage and rehabilitate states of disorder, as well as their disordered subjects. By chronicling the case of a young Haitian refugee who sought asylum in the United States, was detained and then repatriated after manifesting the disordered signs of insecurity, I argue that the Haitian trope of ensekirite captures and prefigures the subjective experience of neomodernity, one for which there is no asylum.  相似文献   

19.
In three year field experiments (2001 – 2003) the growth, yield and productivity of 8 flax cultivars were compared. Cultivars ‘AC Linora’, ‘Flanders’, ‘Linola™ 947’, ‘Norlin’ and ‘Omega’ were obtained from Canada, ‘Barbara’ and ‘Hungarian Gold’ from Hungary and ‘Opal’ from Poland. Apart from the estimation of the yield of aboveground parts dry matter and seed yield the determinations of the primary index value of growth analysis were done and on their basis the indices LAI, LAD, RGR, CGR and HI were calculated. The obtained yield results of the examined flax cultivars show significant genotypic — environmental relationships pertaining to the dynamics of dry matter accumulation and the amount of seed yield. Meteorological conditions in the successive years significantly influenced the particular phases of growth and development of cultivars and the factor which increased the amount of dry matter was the air temperature during the period of plant emergence — budding. During the vegetative season with a large amount of rainfall the average seed yield was about 40 % lower than compared with a year of average precipitation and a warm second part of the second period of flax vegetation. Among the analyzed cultivars a stable yield in all the years was characteristic for cultivars ‘Flanders’, ‘Barbara’ and ‘AC Linora’ (that cultivar, however, during a wet year yielded at a low level). The assimilation leaf surface of the linseed quickly increased during the period from budding to flowering and the accumulation of dry matter of the aboveground parts lasted up to the green maturity. In the successive years of the experiment there were observed significant (linear or logarithmic regressions) relationship between the yield of dry matter and the indices of growth analysis. The biggest values of the CGR indicator were observed for the period from budding to flowering. The maintaining of a high CGR value after plant flowering in the year with a favourable course of climatic parameters was beneficial for a better yield of all flax cultivars. The low values of the RGR index after flowering of cultivar ‘Hungarian Gold’ and ‘Opal’ strictly corresponded to their low yield of seed and straw biomass.  相似文献   

20.
While much research on forest partnerships hitherto has been focused mainly on the drivers behind their formation, the kind of actors and deals involved, and the factors that promote or hinder their success, much less attention has been paid to the dynamic relationships and processes inherent in these partnerships. Based on the study of a partnership process in an indigenous reservation in Colombian Amazonia covering a variety of projects, this paper seeks to fill part of this lacuna by analyzing the partnership as a dynamic ‘discursive battlefield,’ in which objectives and actions are being constantly negotiated. Actors in the Matavén partnership strategically incorporate discursive elements in order to pursue their own interests while also endorsing those that ensure the continuation of collaboration. We conclude that discourses are embedded in partnership micro-politics. On the one hand, discursive shifts occur as a reflection of power balances at given moments. On the other hand, discourses constitute indispensable resources with the potential to both enhance individual actor’s negotiating power and to create opportunities for compromise. Within an ongoing discursive tension between ‘conservation’ and ‘indigenous autonomy,’ flexible notions such as ‘territorial ordering’ prove to be successful in allowing space for manoeuvre and granting conceptual coherence to shifts occurring ‘on the ground.’  相似文献   

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