排序方式： 共有7条查询结果，搜索用时 15 毫秒
1
1.
Daniel Brito 《Biological conservation》2008,141(11):2912-2917
Amphibian declines and extinctions are a worldwide concern. Conservation priorities for amphibians should target threatened taxa (taxonomic targets) and regions with high levels of species endemism (geographical targets). Does published research on amphibian conservation reflect the global taxonomic and geographic priorities? I surveyed six years (2000-2005) of 10 conservation and herpetological journals (Amphibia-Reptilia, Animal Conservation, Applied Herpetology, Biodiversity and Conservation, Biological Conservation, Conservation Biology, Copeia, Herpetologica, Journal of Herpetology and Oryx), and analyzed all articles on amphibians. Attention indexes were calculated for orders, threatened species and biogeographic realms. I also examined how well research from tropical developing nations (with high levels of richness and endemism) are represented in the international literature. Attention indexes results show that the most studied amphibian order is Caudata, whereas Gymnophiona is the least studied one. The same trend is observed for threatened species, with threatened Caudata species receiving proportionally more attention than threatened Anura and Gymnophiona. The biogeographic realms that receive most attention by amphibian conservationists are: Oceania, Nearctic and Palearctic. However, the Neotropical, Afrotropical and Indomalayan are the regions with higher species diversity. Forty-one countries contributed articles, but the majority of amphibian conservation research is conducted by North American and western European researchers. There is urgent need for capacity building in tropical developing nations. Amphibians are more threatened and are declining more rapidly than either birds or mammals. However, amphibian conservation is still misplacing its focus in lower-biodiversity regions and non-threatened species. If such trends are not changed, the consequences for the persistence of amphibians worldwide may be dire. 相似文献
2.
Luca SANTINI Ana BENÍTEZ‐LÓPEZ Gentile Francesco FICETOLA Mark A. J. HUIJBREGTS 《Integrative zoology》2018,13(1):36-45
Body mass is rarely recorded in amphibians, and other body measurements (e.g. snout to vent length, SVL) are generally collected instead. However, length measurements, when used as proxies of body mass in comparative analyses, are problematic if different taxa and morphotypes are included. We developed allometric relationships to derive body mass from SVL measurements. We fitted phylogenetic generalized least square models for frogs (Anura) and salamanders (Caudata) and for several families separately. We tested whether allometric relationships differed between species with different habitat preferences and between morphs in salamanders. Models were fitted with SVL–mass measurements for 88 frog and 42 salamander species. We assessed the predictive performance of the models by cross‐validation. Overall, the models showed high explained variance and low forecasting errors. Models differed among semi‐aquatic, terrestrial and arboreal frogs, and between paedomorphic and non‐paedomorphic salamanders. Body mass estimates derived from our models allow for comparability of studies on multiple taxa and can be used for testing theories built upon evolutionary and ecological processes which are directly related to body mass. 相似文献
3.
Judith A. Simon Joel W. Snodgrass Ryan E. Casey Donald W. Sparling 《Landscape Ecology》2009,24(3):361-373
Many amphibian species rely on both aquatic and terrestrial habitats to complete their life cycles. Therefore, processes operating
both within the aquatic breeding habitat, and in the surrounding uplands may influence species distributions and community
composition. Moreover, changes in land use adjacent to breeding site may degrade aquatic habitats. To assess land use effects
on pond-breeding amphibian assemblages, we investigated relationships between land use, breeding habitat conditions, and breeding
amphibian use of constructed wetlands in urban environments of the Baltimore metropolitan area, USA. Forest and impervious
surface associations with species richness and occurrence occurred at spatial scales ranging from 50 to 1,000 m, with strongest
relationships at 500 m. Forest and impervious surface cover within 1,000 m of ponds were also related to water and sediment
quality, which in turn were capable of explaining a proportion of the observed variation in species richness and occurrence.
Taken together, our results suggest that forest and other land covers within relatively proximal distances to ponds (i.e.,
within 50–1,000 m) may be influencing species richness directly via the provisioning of upland habitat, and indirectly via
influences on within pond habitat quality.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
4.
5.
Diversity erosion beyond the species level: Dramatic loss of functional diversity after selective logging in two tropical amphibian communities 总被引：1，自引：0，他引：1
Assessing the effects of logging on different aspects of biodiversity and general ecosystem properties is of prime importance if the few remaining areas of intact tropical forest are to be efficiently protected. Commonly used measures of biodiversity may only inadequately reflect actual disturbance after logging and studies restricted to only one specific eco-region do not allow for generalizations of results. We hence measured the impact of selective logging on different levels of diversity of two tropical anuran communities in two geographically distinct eco-regions. Species-diversity patterns were incoherent both, within and between studies. In West Africa, species richness did not differ between primary and exploited forest sites, whereas South American anuran communities exhibited higher species richness in primary sites. Yet, in both eco-regions, functional diversity (FD) was higher in primary forest communities. Absolute values of FD were higher in South American anuran communities, despite higher species richness in West African communities. FD was higher in older recovery, as compared to younger recovery states, even though species-diversity did not differ significantly. Three major conclusions can be drawn from our results. 1. Scale matters: it is important to monitor different levels of biodiversity in order to reveal its actual loss after anthropogenic disturbance. 2. Time matters: the disturbance history of a site is important in order to detect patterns that otherwise remain unnoticed. 3. Geographic history matters at the local scale: whereas general patterns at higher diversity levels were identical in both eco-regions, species richness, species diversity and turnover patterns differed. 相似文献
6.
The two brown frogs Rana arvalis and Rana temporaria were monitored at 57 localities (that contained a total of 120 ponds) for up to 17 years each during the years 1989-2005. The analysis summarized below only accounts for trends within sites actually usable for frogs during the analysis period, large scale habitat losses are thus not accounted for. R. arvalis populations tended to increase over the study period. R. temporaria populations displayed no significant change. However, both species displayed significant fluctuations from year to year. These were not correlated between the two species. Localities with permanent ponds tended to display more positive population trends than localities with temporary ponds and ponds in pastures tended to display more positive trends than those in forests. For ponds in cropped fields, where only R. temporaria were found, the trend were also generally negative. Thus, long-term trends suggest that neither species is in decline. Nevertheless, the population trends observed in more exploited habitats are less positive than those in relatively unexploited habitats. We conclude frog populations in agricultural habitats should be more carefully studied to identify the factors behind the decline. The negative trend in temporary ponds are cause for a closer analysis of the effects of weather factors on frog population dynamics. 相似文献
7.
1