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261.
Maintenance of biodiversity through seed banks and botanical gardens, where the wealth of species’ genetic variation may be preserved ex situ, is a major goal of conservation. However, challenges can persist in optimizing ex situ collections if trade-offs exist among cost, effort, and conserving species evolutionary potential, particularly when genetic data are not available. We evaluated the genetic consequences of population preservation informed by geographic (isolation by distance [IBD]) and environmental (isolation by environment [IBE]) distance for ex situ collections for which population provenance is available. We used 19 genetic and genomic data sets from 15 plant species to assess the proportion of population genetic differentiation explained by geographic and environmental factors and to simulate ex situ collections prioritizing source populations based on pairwise geographic distance, environmental distance, or both. Specifically, we tested the impact prioritizing sampling based on these distances may have on the capture of neutral, functional, or putatively adaptive genetic diversity and differentiation. Individually, IBD and IBE explained limited population genetic differences across all 3 genetic marker classes (IBD, 10–16%; IBE, 1–5.5%). Together, they explained a substantial proportion of population genetic differences for functional (45%) and adaptive (71%) variation. Simulated ex situ collections revealed that inclusion of IBD, IBE, or both increased allelic diversity and genetic differentiation captured among populations, particularly for loci that may be important for adaptation. Thus, prioritizing population collections based on environmental and geographic distance data can optimize genetic variation captured ex situ. For the vast majority of plant species for which there is no genetic information, these data are invaluable to conservation because they can guide preservation of genetic variation needed to maintain evolutionary potential within collections.  相似文献   
262.
Coastal fisheries are a critical component of Pacific island food systems; they power village economies and provide nutritious aquatic foods. Many coastal women and men actively fishing in this region rely on multi-species fisheries, which given their extraordinary diversity are notoriously difficult to both characterize, and to manage. Understanding patterns of fishing, diversity of target species and drivers of these patterns can help define requirements for sustainable management and enhanced livelihoods. Here we use a 12-month data set of 8535 fishing trips undertaken by fishers across Malaita province, Solomon Islands, to create fisheries signatures for 13 communities based on the combination of two metrics; catch per unit effort (CPUE) and catch trophic levels. These signatures are in turn used as a framework for guiding suitable management recommendations in the context of community-based resource management. While a key proximate driver of these patterns was fishing gear (e.g. angling, nets or spearguns), market surveys and qualitative environmental information suggest that community fishing characteristics are coupled to local environmental features more than the market value of specific species they target. Our results demonstrate that even within a single island not all small-scale fisheries are equal, and effective management solutions ultimately depend on catering to the specific environmental characteristics around individual communities.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01690-z.  相似文献   
263.
ABSTRACT: The effectiveness of water conservation policies on reduction of water consumption was evaluated by use of a multiple regression predictive model. Data were obtained from eight Iowa communities, with regard to water consumption and water conservation policies adopted during the drought of 1977. The proposed model, which takes precipitation, temperature, month effects, and uniqueness of communities into account, is considered superior to the use of simple percent changes in evaluating the significance of reduction in water consumption due to conservation efforts. Among the variety of policies reviewed, mandatory policies with per capita restrictions were found to be most effective. However, voluntary conservation policies also resulted in significant reduction in some communities located in close proximity to other communities with severer water shortages. High credibility of local governments as to water shortage information was singled out as the most important factor in successful conservation by water resource policymakers of these communities. Use of the proposed predictive model for water consumption was demonstrated. Recommendations regarding future water conservation were made.  相似文献   
264.
本文针对目前环境保护的热点之一——全球和地区性生物多样性保护,对其中的一个基础理论问题,即区域生物多样性评价标准进行了探索;从理论上对制定这一标准的必要性、可行性、生物多样性的基本内涵、区域生物多样性中心标准的意义及标准制定的原则和依据进行了阐述,并在此基础上提出了我国区域生物多样性中心标准的基本框架。  相似文献   
265.
电石工业作为我国重要的基础化工行业,也是高耗能、高污染的行业。由于电石炉烟气自身的特点,使其净化难度大,大量烟气及粉尘带来了严重的环境问题。将电石炉高温烟气作为石灰煅烧的燃料,再将石灰窑产生的烟气用于焦炭干燥,然后将烘干后的废气引出,作为助燃空气直接用管道输送至自备电厂,在利用热烟气中的显热的同时,在锅炉中通过燃烧去除烟气中的大部分污染物,随后烟气进入污染物控制系统中,将其中的污染物去除后排放,可使电石大气污染物达到趋零排放。  相似文献   
266.
江苏省节能减排战略研究   总被引:1,自引:1,他引:1  
江苏省近年经济稳步增长,人民生活水平不断提高,但经济增长的代价是随之增长的能源消耗,导致对资源需求持续增加,对环境的不利影响日益突出,给节能减排工作造成了沉重的压力。在此对江苏省2000年~2006年社会经济发展与节能减排的耦合关系进行了全面分析.重点分析了江苏省经济总量和产业结构与能源消耗和“三废”排放的关联;总结了江苏省的能耗特点和节能减排工作中存在的问题;并根据江苏省千家企业和百家企业的分布以及不同行业“三废”排放量等指标,明确了节能减排工作的区域与行业重点,提出了江苏省的节能减排战略。  相似文献   
267.
煤炭企业节能减排问题与对策   总被引:2,自引:0,他引:2  
通过对煤炭企业能耗状况和排污状况的分析,指出煤炭企业节能减排的紧迫性,并从人才紧缺、企业管理与节能减排工作脱节等方面分析了煤炭企业节能减排工作面临的问题,提出应发展循环经济,通过技术创新、管理创新、提高全员素质,促进煤炭企业节能减排。  相似文献   
268.
How conservation messages are framed will impact the success of our efforts to engage people in conservation action. This is highly relevant in the private land conservation (PLC) sector given the low participation rates of landholders. Using a case study of PLC schemes targeted at Australian landholders, we present the first systematic analysis of communication strategies used by organisations and government departments delivering those schemes to engage the public. We develop a novel approach for analysing the framing of conservation messages that codes the stated benefits of schemes according to value orientation. We categorised the benefits as flowing to either the landholder, to society, or to the environment, corresponding to the egoistic, altruistic and biospheric value orientations that have been shown to influence human behaviour. We find that messages are biased towards environmental benefits. Surprisingly, this is the case even for market-based schemes that have the explicit objective of appealing to production-focussed landholders and those who are not already involved in conservation. The risk is that PLC schemes framed in this way will fail to engage more egoistically oriented landholders and are only likely to appeal to those likely to already be conservation-minded. By understanding the frame in which PLC benefits are communicated, we can begin to understand the types of people who may be engaged by these messages, and who may not be. Results suggest that the framing of the communications for many schemes could be broadened to appeal to a more diverse group (and thus ultimately to a larger group) of landholders.  相似文献   
269.
Domestic energy practices are a topical policy issue, with implications for climate change, energy security and fuel poverty. Accordingly, a growing body of literature examines ways of promoting energy conservation and generation by individuals. However, there has been relatively little discussion of how status and stigma are implicated in these practices, and may act as facilitators or barriers to “behaviour change”. To help address this gap, this article draws both on existing literature and a new UK-based study of people who are attempting to live sustainable lives, to provide insights into how domestic energy practices may be status-enhancing or stigmatising, and how these risks and opportunities can be managed. While energy practices are often understood as “inconspicuous”, it is argued here that in some circumstances individuals may actively manage the visibility of their energy practices. The discussion considers these findings with regard to social power relations, and identifies issues warranting further exploration within the emerging research agenda on energy and equity.  相似文献   
270.
In view of the Brazilian Ten‐Year Energy Expansion Plan 2021, this article presents a discussion on environmental flow (e‐flow). The authors analyze the literature to show the evolution of publications concerning e‐flow releases from the perspective of ecosystems services preservation considering results from different case studies from throughout the world. Finally, two main recommendations are drawn regarding e‐flow are: (1) performing a holistic approach to e‐flow planning, including hydrological, hydraulic, water quality, habitat, and riparian zone considerations; and (2) installing in new structures adequate bottom outlets to allow a range of adjustable e‐flow from reservoir dams to reproduce natural flow variations.  相似文献   
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