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221.
A fungal perspective on conservation biology   总被引:1,自引:0,他引:1       下载免费PDF全文
Hitherto fungi have rarely been considered in conservation biology, but this is changing as the field moves from addressing single species issues to an integrative ecosystem‐based approach. The current emphasis on biodiversity as a provider of ecosystem services throws the spotlight on the vast diversity of fungi, their crucial roles in terrestrial ecosystems, and the benefits of considering fungi in concert with animals and plants. We reviewed the role of fungi in ecosystems and composed an overview of the current state of conservation of fungi. There are 5 areas in which fungi can be readily integrated into conservation: as providers of habitats and processes important for other organisms; as indicators of desired or undesired trends in ecosystem functioning; as indicators of habitats of conservation value; as providers of powerful links between human societies and the natural world because of their value as food, medicine, and biotechnological tools; and as sources of novel tools and approaches for conservation of megadiverse organism groups. We hope conservation professionals will value the potential of fungi, engage mycologists in their work, and appreciate the crucial role of fungi in nature. Una Perspectiva Micótica de la Biología de la Conservación  相似文献   
222.
The potential impacts of payments for environmental services (PES) and protected areas (PAs) on environmental outcomes and local livelihoods in developing countries are contentious and have been widely debated. The available evidence is sparse, with few rigorous evaluations of the environmental and social impacts of PAs and particularly of PES. We measured the impacts on forests and human well‐being of three different PES programs instituted within two PAs in northern Cambodia, using a panel of intervention villages and matched controls. Both PES and PAs delivered additional environmental outcomes relative to the counterfactual: reducing deforestation rates significantly relative to controls. PAs increased security of access to land and forest resources for local households, benefiting forest resource users but restricting households’ ability to expand and diversify their agriculture. The impacts of PES on household well‐being were related to the magnitude of the payments provided. The two higher paying market‐linked PES programs had significant positive impacts, whereas a lower paying program that targeted biodiversity protection had no detectable effect on livelihoods, despite its positive environmental outcomes. Households that signed up for the higher paying PES programs, however, typically needed more capital assets; hence, they were less poor and more food secure than other villagers. Therefore, whereas the impacts of PAs on household well‐being were limited overall and varied between livelihood strategies, the PES programs had significant positive impacts on livelihoods for those that could afford to participate. Our results are consistent with theories that PES, when designed appropriately, can be a powerful new tool for delivering conservation goals whilst benefiting local people.  相似文献   
223.
Sodium is the main cooling medium in the circuit of fourth-generation nuclear reactors, and its leakage constitutes a severe fire hazard because of its high chemical activity. In this study, expandable graphite (EG), which is a traditional sodium fire-extinguishing agent, was modified with zinc borate (ZB) as an intercalator, and the modified EGZB was characterized. Moreover, the effectiveness of the modified EGZB in extinguishing sodium fires was tested using a self-developed fire-extinguishing experimental device. This study's results indicated that EG, EGZB had a smaller particle size, higher thermal stability, higher fire-extinguishing speed, and lower powder mass consumption than EG. During the fire-extinguishing process, ZnO decomposed by ZB captured free radicals and inhibited the combustion reaction. Furthermore, B2O3 was adsorbed on the surface of the EG layer, which strengthened covering and asphyxiation. The findings of this study provide crucial information for effectively controlling fires caused by active metals and metallo-organic compounds.  相似文献   
224.
This study examines people's immediate responses to earthquakes in Christchurch, New Zealand, and Hitachi, Japan. Data collected from 257 respondents in Christchurch and 332 respondents in Hitachi revealed notable similarities between the two cities in people's emotional reactions, risk perceptions, and immediate protective actions during the events. Respondents' physical, household, and social contexts were quite similar, but Hitachi residents reported somewhat higher levels of emotional reaction and risk perception than did Christchurch residents. Contrary to the recommendations of emergency officials, the most frequent response of residents in both cities was to freeze. Christchurch residents were more likely than Hitachi residents to drop to the ground and take cover, whereas Hitachi residents were more likely than Christchurch residents to evacuate immediately the building in which they were situated. There were relatively small correlations between immediate behavioural responses and demographic characteristics, earthquake experience, and physical, social, or household context.  相似文献   
225.
In the past decade Australia has experienced a series of large‐scale, severe natural disasters including catastrophic bushfires, widespread and repeated flooding, and intense storms and cyclones. There appears to be a prima facie case for rebuilding damaged infrastructure to a more disaster resilient (that is, to ‘betterment’) standard. The purpose of this paper is to develop and illustrate a consistent and readily applied method for advancing proposals for the betterment of essential public assets, which can be used by governments at all levels to determine the net benefits of such proposals. Case study results demonstrate that betterment investments have the potential to deliver a positive economic return across a range of asset types and regions. Results, however, are highly sensitive to underlying assumptions; in particular the probability of the natural disaster affecting the infrastructure in the absence of betterment.  相似文献   
226.
In the aftermath of a disaster event, and in the absence of trained professionals, many responsibilities are assumed by uninjured citizens who are willing and able to help, such as care of the injured or search and rescue. These citizens are constrained by communications and logistics problems but are less equipped to deal with them as most often they are cut off from any coordinated assistance. The method proposed in this study would increase the survivability of those injured or trapped by a disaster event by providing a facility to allow citizens to coordinate and share information among themselves. This is facilitated by the proposed deployment and the autonomous management of an ad hoc infrastructure that liaises directly with survivors without central control. Furthermore, as energy concerns present critical constraints to these networks, this research proposes a system of categorising information elements within the network to ensure efficient information exchange.  相似文献   
227.
The twenty‐first century has seen a significant rise in all forms of disasters and this has resulted in military and humanitarian organisations becoming more frequently engaged in the provision of support to those affected. Achieving an efficient and effective logistic preparation and response is one of the key elements in mitigating the impact of such events, but the establishment of mechanisms to deliver an appropriately integrated civil–military approach remains elusive. Not least because of the high percentage of assistance budgets spent on logistics, this area is considered to represent fertile ground for developing improved processes and understanding. In practice, the demands placed on civilian and military logisticians are broadly similar, as is the solution space. Speaking a common language and using common concepts, it is argued, therefore, that the logistic profession should be in the vanguard of the development of an improved civil–military interface.  相似文献   
228.
反硝化过程是土壤氮素循环的重要过程之一,与土壤氮肥损失和温室气体排放紧密相关。通过分析不同施肥方式对东北旱田黑土nirK型和nirS型反硝化细菌群落结构的影响及其与N2O排放的关系,证实黑土中nirK型比nirS型反硝化细菌多样性丰富,且更易受土壤理化性质的影响。施入化肥会降低东北旱田黑土反硝化细菌多样性、N2O释放量和土壤养分含量,而有机肥的施入虽然可提高土壤养分含量,但是也会显著增加土壤反硝化作用,存在潜在的负面环境效应。因此对黑土地的保护要积极推行种养结合,建立可循环农业体系;适当配施有机肥料,调节黑土微生物活力;大力完善相关制度,营造科学管理新规范,从而构建我国黑土保护的立体格局。  相似文献   
229.
External organic carbon sources are needed to provide electron donors for the denitrification of wastewater with a low COD/NO3--N(C/N) ratio, increasing the treatment cost. The economic strategy is to enhance the bioactivity and/or biodiversity of denitrifiers to efficiently utilize organic substances in wastewater. In this study, novel zero-valent iron(ZVI) composite carriers were prepared and implemented in a suspended carrier biofilm reactor to enhance the bioactivity an...  相似文献   
230.
Geography provides the basic building blocks for the study of resource use and sustainable development, inasmuch as it categorizes the human environment. Within the environment are resources that are needed for the survival of society. As resources are largely limited and finite, humans as agents of change must employ techniques that allow an efficient and lasting use of the available resources in their environment. This paper discusses the nexus between geography, resource exploitation, use, and sustainable development. It also discusses the characteristics, types, and classification of resources, development and sustainable development as well as the challenges and strategies for attaining sustainable development, particularly in developing countries.  相似文献   
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