首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到6条相似文献,搜索用时 0 毫秒
1.
There is an urgent need for a new conservation approach as mere designation of protected areas, the primary approach to conserving biodiversity, revealed its low conservation efficiency and inability to cope with numerous challenges faced by nature in the Anthropocene. The paper discusses the new concept, which proposes that ecological restoration becomes an integral part of conservation planning and implementation, and is done using threatened plant species that are introduced not only into locations where they currently grow or grew in the recent past, but also into suitable locations within their potential distribution range. This new concept is called conservation-oriented restoration to distinguish it from the traditional restoration. Although the number of restoration projects focusing on recreation of once existing natural habitats is instantly growing, the majority of ecological restoration projects, in contrast to conservation-oriented restoration, have predominantly utilitarian goals, e.g.improvement or air quality, erosion control or soil replenishment. Conservation-oriented restoration should not be seen as an alternative either to the latter, or to the conservation dealing with particular threatened species(species-targeted conservation). These three conservation approaches, traditional ecological restoration, species-targeted conservation, and conservation-oriented restoration differ not only in broadly defined goals and attributes of their targets, but also in the types of ecosystems they are applicable to, and complement each other in combating global deterioration of the environment and biodiversity loss.  相似文献   

2.
There is an urgent need for a new conservation approach as mere designation of protected areas, the primary approach to conserving biodiversity, revealed its low conservation efficiency and inability to cope with numerous challenges faced by nature in the Anthropocene. The paper discusses the new concept, which proposes that ecological restoration becomes an integral part of conservation planning and implementation, and is done using threatened plant species that are introduced not only into locations where they currently grow or grew in the recent past, but also into suitable locations within their potential distribution range. This new concept is called conservation-oriented restoration to distinguish it from the traditional restoration. Although the number of restoration projects focusing on recreation of once existing natural habitats is instantly growing, the majority of ecological restoration projects, in contrast to conservation-oriented restoration, have predominantly utilitarian goals, e.g.improvement or air quality, erosion control or soil replenishment. Conservation-oriented restoration should not be seen as an alternative either to the latter, or to the conservation dealing with particular threatened species(species-targeted conservation). These three conservation approaches, traditional ecological restoration, species-targeted conservation, and conservation-oriented restoration differ not only in broadly defined goals and attributes of their targets, but also in the types of ecosystems they are applicable to, and complement each other in combating global deterioration of the environment and biodiversity loss.  相似文献   

3.
Human-wildlife conflicts (HWC) pose a growing threat to biodiversity worldwide and solutions can be as sound as the understanding of the HWC itself. Conservation biologists therefore must carefully examine their local situations to inform on which approach and strategies may be best. In this context, Mauritius implemented what may be the first mass-culls of an already threatened native species when it culled the flying fox (Pteropus niger) in 2015 and 2016 to try increase fruit producers’ profits. Although the Red List category of the species consequently worsened to ‘Endangered’ and fruit production dropped substantially, a third mass-cull was decided in 2018. A critical analysis is important to draw lessons that may help to prevent recurrences particularly that HWC involving Pteropus spp. are common and set to worsen. We synthesized the best literature available locally and also elsewhere in relevant situations, to critically appraise the setting, nature, timeline of events and outcome of both completed mass-culling campaigns to explore why and how they happened so as to help towards devising better approaches to such conflicts. The idea to cull P. niger originated around 2002 and a small cull was done in 2006. The first mass-cull started immediately after Mauritius’ biodiversity protection law was weakened in 2015 primarily to legalize culls of threatened native species, but still breached the law in place then. The 2016 mass-cull was recommended in line with the law, but was not evidence-based and consequently did not result in improved profits of fruit producers. Appeals supported by best scientific evidence from local and international organizations and conservationists to the effect that culls will not increase fruit production, but instead further endanger the species, were ignored. To forestall recurrences here and elsewhere, it matters to recognize their precursor signs and the conditions that favoured them including why the mass-culls were not stopped. The events provide a rare opportunity to explore the strategy that was used by conservationists and open the way to propose impactful alternatives or additional actions instead. The situation also exemplifies an eroding commitment towards biodiversity conservation, eased by withdrawal from evidence-based policy that suit short term goals of election cycles at the expense of longer term environmental interests.  相似文献   

4.
A high throughput and specific method using ultra performance liquid chromatography tandem mass spectrometry (UPLC–MS/MS) was developed for the simultaneous determination of diltiazem and its two metabolite (N-desmethyldiltiazem and O-desacetyldiltiazem) in human plasma. A one-step liquid–liquid extraction (LLE) with methyl-t-butyl ether (MTBE) involved for the extraction of diltiazem (DLTZ), metabolites (DMeD and DAcD) and internal standard. Analytes were chromatographed on a ACQUITY UPLC? BEH C18 column (100 mm × 2.1 mm, i.d., 1.7 μm) with isocratic elution at a flow rate of 0.2 mL/min using 10 mM ammonium acetate buffer–acetonitrile (25:75, v/v). The Quattro Premier XE LC–MS/MS was operated under the multiple reaction-monitoring mode (MRM) using the electrospray ionization technique. Using 300 μL plasma, the method was validated over the concentration range 0.48–639.9 ng/mL for DLTZ and 0.24–320.1 for DMeD and 0.24–320.7 ng/mL for DAcD, with a lower limit of quantification of 0.48 ng/mL for DLTZ and 0.24 ng/mL for metabolites. The intra- and inter-day precision and accuracy were within 10.0%. The recovery was 77.4%, 76.0%, 74.5% and 74.1% for DLTZ, DMeD, DAcD and Ziprasidone, respectively. Total run time was 2.0 min only.  相似文献   

5.
《Acta Oecologica》2003,24(3):169-174
We studied a congeneric species pair that shows very different abundances in Estonia — Viola elatior occurs in only five localities in mesic calcareous grasslands, while Viola mirabilis is abundant in mesic calcareous grasslands and forests all over the country. Both species were sown in patches of mesic calcareous grassland, in clipped and untreated plots. Both species were established successfully after sowing, indicating that they both may be dispersal limited to the same extent. V. elatior showed higher fecundity in the second year than V. mirabilis. V. elatior was more sensitive to the availability of light. In the first year, V. elatior established more successfully in clipped plots than V. mirabilis. In the second year, the number of established V. elatior individuals decreased in unmanaged plots, where competition for light was more severe. Since many calcareous grasslands in Estonia have been abandoned and the standing crop, as well as the cover of shrubs and trees, has increased, sensitivity to light competition may be one reason why V. elatior has become more rare. It cannot be the only reason for its rarity in the whole region, since many other grassland species that are vulnerable to reduced light in overgrown unmanaged grassland communities still occur in much higher numbers in the country. It was hypothesised that historical factors, e.g. relatively late arrival in the region, may also be behind the rarity of V. elatior.  相似文献   

6.
In this paper,a class of linear parabolic systems of singularly perturbed second-order differential equations of reaction-diffusion type with initial and Robin boundary conditions is considered.The components of the solution u→ of this system are smooth,whereas the components of αu→/αx exhibit parabolic boundary layers.A numerical method composed of a classical finite difference scheme on a piecewise uniform Shishkin mesh is suggested.This method is proved to be first-order convergent in time and essentially first-order convergent in the space variable in the maximum norm uniformly in the perturbation parameters.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号