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1.
Quantifying the spatial distribution of taxa is an important prerequisite for the preservation of biodiversity, and can provide a baseline against which to measure the impacts of climate change. Here we analyse patterns of marine mammal species richness based on predictions of global distributional ranges for 115 species, including all extant pinnipeds and cetaceans. We used an environmental suitability model specifically designed to address the paucity of distributional data for many marine mammal species. We generated richness patterns by overlaying predicted distributions for all species; these were then validated against sightings data from dedicated long-term surveys in the Eastern Tropical Pacific, the Northeast Atlantic and the Southern Ocean. Model outputs correlated well with empirically observed patterns of biodiversity in all three survey regions. Marine mammal richness was predicted to be highest in temperate waters of both hemispheres with distinct hotspots around New Zealand, Japan, Baja California, the Galapagos Islands, the Southeast Pacific, and the Southern Ocean. We then applied our model to explore potential changes in biodiversity under future perturbations of environmental conditions. Forward projections of biodiversity using an intermediate Intergovernmental Panel for Climate Change (IPCC) temperature scenario predicted that projected ocean warming and changes in sea ice cover until 2050 may have moderate effects on the spatial patterns of marine mammal richness. Increases in cetacean richness were predicted above 40° latitude in both hemispheres, while decreases in both pinniped and cetacean richness were expected at lower latitudes. Our results show how species distribution models can be applied to explore broad patterns of marine biodiversity worldwide for taxa for which limited distributional data are available. 相似文献
2.
Polychaetes as surrogates for marine biodiversity: lower taxonomic resolution and indicator groups 总被引:8,自引:0,他引:8
Due to conservation needs, reliable rapid-assessment methods for mapping of biodiversity are needed. One approach is to use surrogates, i.e. quantities that correlate strongly with the number of species, but are easier to obtain. The purpose of this paper is to test two polychaete surrogates, one for higher taxa and one for indicator groups, that will facilitate prediction of species richness in marine soft-bottom communities. Soft sediment is an important habitat which covers most of the ocean bottom. Data on polychaetes from the North Atlantic were used since polychaetes are often numerically dominant in the benthic assemblages, both with regard to the number of species and their abundance. In the polychaete assemblages along the Norwegian coast, richness at the genus, family and order level were significantly, linearly correlated to total species richness (r 0.92). Polychaetes in the order Terebellida were found to be a good indicator of polychaete species richness and to a lesser extent also of whole benthic assemblages. The group Terebellida is potentially well suited as an indicator group, since it contains long-lived, large species that are easy to sort from the sediment and it is well defined taxonomically. Although promising as proxies for species richness in marine biodiversity studies, the use of lower taxonomic resolution and indicator groups requires further investigations in more local areas where there are conservation issues. 相似文献
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4.
Conservation planning requires knowledge of the distribution of all species in the area of interest. Surrogates for biodiversity are considered as a possible solution. The two major types are biological and environmental surrogates. Here, we evaluate four different methods of hierarchical clustering, as well as one non-hierarchical method, in the context of producing surrogates for biodiversity. Each clustering method was used to produce maps of both surrogate types. We evaluated the representativeness of each clustering method by finding the average number of species represented in a set of sites, one site of each domain, which was carried out with Monte-Carlo permutations procedure. We propose an additional measure of surrogate performance, which is the degree of evenness of the different domains, e.g., by calculating Simpson's diversity index. Surrogates with low evenness leave little flexibility in site selection since often some of the domains may be represented by a single or very few sites, and thus surrogate maps with a high Simpson's index value may be more relevant for actual decision making. We found that there is a trade-off between species representativeness and evenness. Centroid clustering represented the most species, but had very low values of evenness. Ward's method of minimum variance represented more species than a random choice, and had high evenness values. Using the typical evaluation measures, the Centroid clustering method was most efficient for surrogate production. However, when Simpson's index is also considered, Ward's method of minimum variance is more appropriate for managers. 相似文献
5.
Chase J 《PLoS biology》2012,10(3):e1001294
A novel hierarchical framework integrates the effects of time, area, productivity, and temperature at their respective relevant scales and successfully predicts the latitudinal gradient in global vertebrate diversity. 相似文献
6.
Bernd Siebenhüner 《Biodiversity and Conservation》2007,16(1):259-274
The paper presents a case study analysing the effects of the Secretariat of the Convention on Biological Diversity as an intergovernmental organisation. Within the study, the effects of organisations are measured by their outcome, i.e. the influence on the behaviour of other actors such as national governments. Three forms of outcomes are being distinguished, namely knowledge brokerage and diffusion, capacity building, and negotiation facilitation. In addition, the paper tries to explain the observed effects on the basis of internal and external variables. The CBD Secretariat has been established in 1992 and is now located in Montreal with about 70 employees. As most other secretariats of international conventions, it is the main organiser and facilitator of the convention process. The empirical material shows that the Secretariat has a measurable influence on the intergovernmental cooperative process which can be attributed to the effective internal management processes and the qualities of its leaders. Lacking capacity building functions and highly selective effects with regard to the provision of knowledge are explained by the limited formal autonomy and the structure of the global biodiversity problem. 相似文献
7.
Background
The cataloging of marine prokaryotic DNA sequences is a fundamental aspect for bioprospecting and also for the development of evolutionary and speciation models. However, large amount of DNA sequences used to quantify prokaryotic biodiversity requires proper tools for storing, managing and analyzing these data for research purposes. 相似文献8.
Batáry P Báldi A Kleijn D Tscharntke T 《Proceedings. Biological sciences / The Royal Society》2011,278(1713):1894-1902
Agri-environmental management (AEM) is heralded as being key to biodiversity conservation on farmland, yet results of these schemes have been mixed, making their general utility questionable. We test with meta-analysis whether the benefits of AEM for species richness and abundance of plants and animals are determined by the surrounding landscape context. Across all studies (109 observations for species richness and 114 observations for abundance), AEM significantly increased species richness and their abundance. More specifically, we test the hypothesis that AEM benefits species richness and abundance (i.e. increases the difference between fields with and without AEM) more in simple than in complex landscapes. In croplands, species richness but not abundance was significantly enhanced in simple but not in complex landscapes. In grasslands, AEM effectively enhanced species richness and abundance regardless of landscape context. Pollinators were significantly enhanced by AEM in simple but not in complex landscapes in both croplands and grasslands. Our results highlight that the one-size-fits-all approach of many agri-environmental programmes is not an efficient way of spending the limited funds available for biodiversity conservation on farmland. Therefore, we conclude that AEM should be adapted to landscape structure and the species groups at which they are targeted. 相似文献
9.
Limited by the availability of data, conservation planners must use surrogates for biodiversity when selecting conservation areas. Although several methods have been proposed for selecting surrogates, no clear set of species attributes have been described that allow for the efficient a priori selection of surrogate groups. We used a database of 1449 species in two regions of the United States to (1) examine the consistency in the performance of simple taxonomic-based surrogates of biodiversity and (2) test five hypotheses proposed to explain surrogate performance. First, we compared the ability of sites selected to protect members of seven surrogate groups to protect non-surrogate species in the north-western United States and in the Middle-Atlantic region of the eastern United States. Then, in a separate analysis, we tested whether surrogate performance could be explained by (1) taxonomic diversity; (2) nested species distributions; (3) hotspots of biodiversity; (4) species range sizes; (5) environmental diversity. Our first analysis revealed little consistency in the performance of surrogates in the two different study regions. For example, butterflies provided protection for 76% of all other species in the north-western United States but only 56% of all other species in the eastern United States. Our second analysis revealed only weak associations between species characteristics and surrogate performance. Furthermore, these associations proved inadequate for selecting successful surrogates across study regions. Overall, our results suggest that in lieu of searching for optimal surrogate groups, research efforts will be better spent by developing alternative methods for assessing conservation value in areas where data on species distributions are limited. 相似文献
10.
Jari Niemelä Johan Kotze Allan Ashworth Pietro Brandmayr Konjev Desender Tim New Lyubomir Penev Michael Samways John Spence 《Journal of Insect Conservation》2000,4(1):3-9
We introduce an initiative to assess and compare landscape changes related to human activities on a global scale, using a single group of invertebrates. The GLOBENET programme uses common field methodology (pitfall trapping), to appraise assemblages of ground beetles (Coleoptera, Carabidae) in visually-similar land-mosaics (urban-rural gradients). Carabids were selected as the focal taxon as they are sufficiently varied (both taxonomically and ecologically), abundant and sensitive to the environment. However, work on other taxa is comparable with the GLOBENET framework. The continuum of decreasing human pressure from city centres into the surrounding countryside was selected to represent human-caused disturbance for this initial stage of GLOBENET because these gradients can be found virtually all over the world. Through the broad-scale assessment envisioned in the GLOBENET programme, we seek to separate general, repeated effects on biodiversity from those that depend on local environments or particular biotic assemblages. Based on this understanding we aim to develop simple tools and protocols for assessing ecological effects of human-caused landscape changes, which could help to sustainably manage landscapes for biodiversity and for human requirements. For instance, the response of different functional groups of carabids to these landscape changes may help guide management practices. Further GLOBENET developments and information are available at our website: http://www.helsinki.fi/science/globenet/ 相似文献
11.
Question: What is the relative importance of environmental and spatial factors for species compositional and phylogenetic turnover? Location: High‐rainfall zone of the Southwest Australian Floristic Region (SWAFR). Methods: Correlates of species compositional turnover were assessed using quadrat‐based floristic data, and establishing relationships with environmental and spatial factors using canonical correspondence analyses and Mantel tests. Between‐quadrat phylogenetic distance measures were computed and examined for correlations with environmental and spatial attributes. Processes structuring pa2t2terns of beta diversity were also evaluated within four broad floristic assemblages defined a priori. Results: Floristic diversity was strongly related to environmental attributes. A low significance of spatial variables on assemblage patterns suggested no evident effect of dispersal limitations. Species compositional turnover was especially high within the swamp and outcrop assemblage. Phylogenetic turnover was closely coupled to species compositional turnover, implying the occurrence of many locally endemic and phylogenetically relict taxa. Beta diversity patterns within assemblages were also significantly correlated with the local environment, and relevant correlates differed between floristic assemblage types. Conclusion: Phylogenetic diversity in the SWAFR high‐rainfall zone is clustered within edaphic microhabitats in a generally subdued landscape. A clustered rather than dispersed distribution of phylogenetic diversity increases the probability of significant plant diversity loss during periods of climate change. Climate change susceptibility of the region's flora is accordingly estimated to be high. We highlight the conservation significance of swamp and outcrops that are characterized by distinct hydrological properties and may provide refugial habitat for plant diversity during periods of moderate climate change. 相似文献
12.
Cross-taxon congruence has been suggested as an efficient tool in conservation planning and biodiversity monitoring. It corresponds to the degree to which patterns in assemblage structure in a set of sites are similar among different taxonomic groups. If different groups ordinate the sampling sites similarly, they are concordant and this information is frequently used as an indicative that one group could be used as a surrogate for the other. Using spatiotemporal benthic data from a biodiverse coastal ecosystem (the Araçá Bay in southeast Brazil), we first assessed if macro- and meiofaunal assemblages inhabiting marine soft-sediments show concordant patterns. Then, we used multi- and univariate analysis to examine the relationship of both groups with the environment. Macro- and meiofaunal assemblages exhibited strong congruent patterns in all periods analyzed. Moreover, both groups responded to similar environmental features and their ordination patterns matched those generated by the environmental data. These results show that the patterns of concordance are probably mediated by similar responses to environmental gradients. Overall, our results suggest the potential for use of the surrogacy approach in conservation planning and monitoring purposes of marine benthic biodiversity, and that macro- and meiofauna can be used as a surrogate for each other. 相似文献
13.
Clément Pimouguet Mélanie Le Goff Rodolphe Thiébaut Jean Fran?ois Dartigues Catherine Helmer 《CMAJ》2011,183(2):E115-E127
Background
We conducted a meta-analysis of randomized controlled trials to assess the effectiveness of disease-management programs for improving glycemic control in adults with diabetes mellitus and to study which components of programs are associated with their effectiveness.Methods
We searched several databases for studies published up to December 2009. We included randomized controlled trials involving adults with type 1 or 2 diabetes that evaluated the effect of disease-management programs on glycated hemoglobin (hemoglobin A1C) concentrations. We performed a meta-regression analysis to determine the effective components of the programs.Results
We included 41 randomized controlled trials in our review. Across these trials, disease-management programs resulted in a significant reduction in hemoglobin A1C levels (pooled standardized mean difference between intervention and control groups −0.38 [95% confidence interval −0.47 to −0.29], which corresponds to an absolute mean difference of 0.51%). The finding was robust in the sensitivity analyses based on quality assessment. Programs in which the disease manager was able to start or modify treatment with or without prior approval from the primary care physician resulted in a greater improvement in hemoglobin A1C levels (standardized mean difference −0.60 v. −0.28 in trials with no approval to do so; p < 0.001). Programs with a moderate or high frequency of contact reported a significant reduction in hemoglobin A1C levels compared with usual care; nevertheless, only programs with a high frequency of contact led to a significantly greater reduction compared with low-frequency contact programs (standardized mean difference −0.56 v. −0.30, p = 0.03).Interpretation
Disease-management programs had a clinically moderate but significant impact on hemoglobin A1C levels among adults with diabetes. Effective components of programs were a high frequency of patient contact and the ability for disease managers to adjust treatment with or without prior physician approval.Despite well-established recommendations for diabetes care,1–3 quality of care still needs to be improved. Although many nonpharmacologic strategies (patient education, psychological intervention, dietary education, self-monitoring and telemedicine) have been developed, their effectiveness is still unclear.4–6 “Disease management” is a structured, multi-faceted intervention that includes several of the above-mentioned components. In two recent meta-analyses, disease management was associated with an improvement in glycemic control, as assessed by a mean reduction in hemoglobin A1C concentration of 0.52% and 0.81%.7,8 Disease management seems to be more effective than single strategies such as clinician education, patient education or promotion of self-management.7Because disease-management programs are heterogeneous, the effective components need to be identified to improve program implementation. Previous studies have evaluated the efficacy of some program components.7,8 Independent medication changes by the disease manager appear to be particularly effective.7 However, other important factors such as the intensity of the intervention have not been previously evaluated.We conducted a meta-analysis of randomized controlled trials (RCTs) involving adults with type 1 or 2 diabetes mellitus that evaluated the effect of disease-management programs on hemoglobin A1C levels. We determined the effective components of the programs, considering both the type of component and the intensity of the intervention. 相似文献14.
Changes in marine biodiversity through the Phanerozoic correlate much better with hyperbolic model (widely used in demography and macrosociology) than with exponential and logistic models (traditionally used in population biology and extensively applied to fossil biodiversity as well). The latter models imply that changes in diversity are guided by a first-order positive feedback (more ancestors, more descendants) and/or a negative feedback arising from resource limitation. Hyperbolic model implies a second-order positive feedback. The hyperbolic pattern of the world population growth arises from a second-order positive feedback between the population size and the rate of technological growth. The hyperbolic character of biodiversity growth can be similarly accounted for by a feedback between the diversity and community structure complexity. The similarity between the curves of biodiversity and human population probably comes from the fact that both are derived from the interference of the hyperbolic trend with cyclical and stochastic dynamics. 相似文献
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Motoki Higa Yuichi Yamaura Masayuki Senzaki Itsuro Koizumi Takeshi Takenaka Yoshiyuki Masatomi Kunikazu Momose 《Biodiversity and Conservation》2016,25(10):1829-1841
Charismatic megafauna have been used as icons and financial drivers of conservation efforts worldwide given that they are useful surrogates for biodiversity in general. However, tests of this premise have been constrained by data limitations, especially at large scales. Here we overcome this problem by combining large-scale citizen-sourced data with intensive expert observations of two endangered charismatic species, Blakiston’s fish owl (forest specialist) and the red-crowned crane (wetland specialist). We constructed large-scale maps of species richness for 52 forest and 23 grassland/wetland bird species using hierarchical community modeling and citizen-sourced data at 1, 2, 5, and 10-km grid resolutions. We compared the species richness of forest and grassland/wetland birds between the breeding and non-breeding sites of the two charismatic birds at each of the four spatial resolutions, and then assessed the scale dependency of the biodiversity surrogates. Regardless of the habitat amounts, owl and crane breeding sites had higher forest and grassland/wetland bird species richness, respectively. However, this surrogacy was more effective at finer scales (1–2-km resolutions), which corresponds to the charismatic species’ home range sizes (up to 9.4 ± 2.0 km2 for fish owls, and 3–4 km2 for cranes). Species richness showed the highest spatial variations at 1–2-km resolutions. We suggest that the agreement of functional scales between surrogate species and broader biodiversity is essential for successful surrogacy, and that habitat conservation and restoration targeting multiple charismatic species with different specialties can complement to biodiversity conservation. 相似文献
17.
Global knowledge about the spatial distribution of species is orders of magnitude coarser in resolution than other geographically-structured environmental datasets such as topography or land cover. Yet such knowledge is crucial in deciphering ecological and evolutionary processes and in managing global change. In this review, we propose a conceptual and cyber-infrastructure framework for refining species distributional knowledge that is novel in its ability to mobilize and integrate diverse types of data such that their collective strengths overcome individual weaknesses. The ultimate aim is a public, online, quality-vetted 'Map of Life' that for every species integrates and visualizes available distributional knowledge, while also facilitating user feedback and dynamic biodiversity analyses. First milestones toward such an infrastructure have now been implemented. 相似文献
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BIOS is a computerised database system for holding species distributiondata. Emphasis has been placed on the flexibility in which storedinformation can be accessed. Multiple retrieval pathways permitsimple enquiries to be answered or complicated interrogationsequences for statistical treatment of data. The structuralorganisation of the database is explained and details of itscontents are listed. Examples of applications in the fieldsof zoogeography and ecology are given together with illustrations. 相似文献
20.
Fredrik Dalerum Michael J. Somers Kyran E. Kunkel Elissa Z. Cameron 《Biodiversity and Conservation》2008,17(12):2939-2949
Biodiversity in southern Africa is globally extraordinary but threatened by human activities. Although there are considerable
biodiversity conservation initiatives within the region, no one has yet assessed the potential use of large carnivores in
such actions. Surrogate approaches have often been suggested as one such way of capitalizing on large carnivores. Here we
review the suitability of the large carnivore guild (i.e., brown hyaena Hyaena hyaena, spotted hyaena Crocuta crocutta, cheetah Acinonyx jubatus, leopard Panthera pardus, lion Panthea leo and African wild dog Lycaon pictus) to act as surrogate species for biodiversity conservation in southern Africa. We suggest that the guild must be complete
for the large carnivores to fully provide their role as ecological keystones. The potential for large carnivores to act as
umbrella and indicator species seems limited. However, self-sustaining populations of large carnivores may be useful indicators
of unfragmented landscapes. Moreover, diversity within the large carnivore guild may reflect overall biodiversity. Although
the global appeal of the large African carnivores makes them important international flagships, we stress that international
conservation funding must be linked to local communities for them to be important also locally. In summary, we suggest that
the flagship value of these large carnivores should be used to promote biodiversity conservation in the region, and that the
suggested relationship between large carnivore diversity and overall biodiversity is empirically tested. Finally we suggest
that direct conservation activities should focus on enhancing the keystone values of large carnivores through complete guild
conservation and restoration. 相似文献