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161.
Proponents of the local food movement point to its environmental, economic, and social benefits, yet there is little research on the extent to which particular local food projects live up to these promises. Vermont leads the country in farm stands, direct-to-consumer sales, and farmers’ markets per capita and the town of Hardwick, Vermont has received substantial media attention for its growing economy based on new food and agriculture businesses, including being the subject of a book entitled The Town that Food Saved. Using interviews with local food participants and analysis of US Census data, the paper assesses the impact of the local food economy in Hardwick using environmental, economic, and social outcomes. The paper also examines how the agricultural renaissance there has been accepted, resisted, and shaped by local actors. Using Census data, the paper finds that between 2000 and 2016, the unemployment rate in Hardwick remained steady, mean incomes increased, and 296 new jobs have been retained. In addition, the percentage of families in Hardwick with income below the poverty level decreased between 2000 and 2016, and the percentage of families accessing supplemental nutrition assistance program (SNAP) benefits increased. The paper also finds that many participants in the Hardwick food economy have concerns about the accessibility, affordability, and inclusivity of the newer food-based projects there. The paper concludes with a discussion of the ways in which Hardwick fulfils some of the hopes and concerns of the local food movement, and the potential for place-based agricultural development.  相似文献   
162.
国家公园建设背景下的公益型保护地研究进展   总被引:1,自引:1,他引:0       下载免费PDF全文
当前我国自然保护地体系改革正处于关键时期,公益型保护地是一种利用社会公益力量,由政府监督、民间管理并协调保护与发展的新型保护地模式。该模式注重社会公益力量在自然保护地建设中的作用,能够补充已有保护地资金、技术和人力的不足,填补了我国目前保护地体系的空缺。本文论述了国家公园建设背景下的公益保护地的内涵,分析了当前公益保护地的特征,讨论了国内外公益型保护地的运营管理机制,包括土地权利的获得、基于协议保护机制的保护地运营、特许经营在保护地的实施和社区保护模式的成功经验。今后我国公益型保护地的建设应鼓励公益组织与民间力量参与,在管理理念上应坚持保护第一和公益性,促进管理体制转变和科学划定界限,并完善公益组织参与保护地建设的激励和监督机制。  相似文献   
163.
利用深圳及周边地区22个环保监测站的PM_(2.5)小时数据、深圳市152个高密度(2.5 km×2.5 km)自动气象站及3部边界层风廓线仪的探测数据,分析了深圳市局地PM_(2.5)污染事件的时空变化特征及其背景环流特征.结果表明:深圳市西北角和东北角是局地PM_(2.5)污染最频繁的2个区域,局地污染事件发生次数约占总污染事件次数的40%,每日夜间至次日凌晨是局地污染高发期.各个季节局地PM_(2.5)污染发生的大尺度环流形势不同,春季为变性高压脊配合西南低槽发展型,夏季为热带气旋外围环流影响型,秋季为副高控制下的弱高压脊型,冬季主要为冷锋前、弱高压脊或均压场控制型.局地海-陆、丘陵-平原热力差异造成的局地环流易导致地面弱风和局地辐合的出现,成为诱发局地PM_(2.5)污染的直接原因.  相似文献   
164.
气象条件对河北廊坊城市空气质量的影响   总被引:2,自引:0,他引:2       下载免费PDF全文
气象条件是影响大气污染的重要因子.利用2013年3月—2014年2月廊坊颗粒物质量浓度监测资料、自动气象站观测资料和欧洲中期天气预报中心再分析资料,采用多种统计方法分析气象与污染的关系,量化天气形势和局地气象条件对城市颗粒物质量浓度变化的贡献.结果表明:天气形势是决定局地气象要素和城市空气质量的重要因子.当廊坊位于高压中心或高压后部时,大气层结稳定,易造成重污染;当廊坊位于高压前部(气压梯度较大)时,大气层结不稳定,易于污染物输送和扩散.利用客观天气分型结合污染物质量浓度统计分析方法,可以量化天气形势对城市空气质量的影响.在局地气象要素中,能见度与ρ(PM2.5)、ρ(PM10)相关性最高(相关系数分别为-0.75和-0.53,下同),其次依次为风速(-0.45和-0.31)、相对湿度(0.41和0.25)和温度(-0.15和-0.06).通过污染物浓度与局地风场关系分析发现,廊坊颗粒物质量浓度受天津市、河北省南部区域输送的影响明显,受北京区域输送的影响相对较弱.研究显示,气象条件可以解释廊坊ρ(PM2.5)和ρ(PM10)日均值变化的56%和49%,其在冬季对颗粒物质量浓度影响最为显著,春秋季次之,夏季影响最小.   相似文献   
165.
为了提高多目标遗传算法Pareto解的局部最优性,本文将快速非支配遗传算法(NSGAII)与一种迭代式的局部搜索算法(Hill Climber with Step,HCS)相结合,开发了一种新的混合多目标遗传算法NSGAII-HCS.利用CONV1和ZDT6两个经典的多目标优化函数对NSGAII-HCS的性能进行测试,与传统的多目标算法NSGAII相比,CONV1得到的Pareto锋面与真实Pareto最优解锋面的平均距离由5.49减小到1.74,ZDT6则由0.16减小到0,表明NSGAII-HCS在保证解多样性的前提下,能使解接近或收敛到真实的Pareto最优解锋面.最后,将NSGAII-HCS与地下水流模拟软件MODFLOW和溶质运移模拟软件MT3DMS相耦合,并应用到一个理想的二维地下水污染修复管理模型中,结果分析表明该方法可为地下水污染治理提供多样的和收敛的Pareto管理策略,是一种稳定可靠的多目标优化方法.  相似文献   
166.
Objective: The objective of this study was to leverage a state health department's operational data to allocate in-kind resources (children's car seats) to counties, with the proposition that need-based allocation could ultimately improve public health outcomes.

Methods: This study used a retrospective analysis of administrative data on car seats distributed to counties statewide by the Georgia Department of Public Health and development of a need-based allocation tool (presented as interactive supplemental digital content, adaptable to other types of in-kind public health resources) that relies on current county-level injury and sociodemographic data.

Results: Car seat allocation using public health data and a need-based formula resulted in substantially different recommended allocations to individual counties compared to historic distribution.

Conclusions: Results indicate that making an in-kind public health resource like car seats universally available results in a less equitable distribution of that resource compared to deliberate allocation according to public health need. Public health agencies can use local data to allocate in-kind resources consistent with health objectives; that is, in a manner offering the greatest potential health impact. Future analysis can determine whether the change to a more equitable allocation of resources is also more efficient, resulting in measurably improved public health outcomes.  相似文献   

167.
伴随经济的发展,中国环境问题日益严重,环境部门的环境治理力度有待加强.长期以来,环境部门应改变传统的重微观层面环境治理职责的实施,改变轻宏观层面环境治理结构架构的做法,调整环境治理方式,充分发挥环境保护多元主体的积极性,突出环境部门在环境治理中的主导作用,明确环境责任.环境责任的关键在于转变环境治理结构中的角色定位,变管理为治理,充分调动多方面力量参与到环境治理,尤其应当重视企业和公众的力量,充分参与治理,实现环境善治.  相似文献   
168.
Abstract:  The use of local ecological knowledge (LEK) has been advocated for biodiversity monitoring and management. To date, however, it has been underused in studying wild populations of animals and, particularly, in obtaining quantitative abundance estimates. We evaluated LEK as a tool for collecting extensive data on local animal abundance and population trends. We interviewed shepherds in southeastern Spain, asking them to estimate the local abundance of the terrestrial tortoise Testudo graeca . We quantified reliability of abundance estimates derived from interviews by comparing them with those obtained from standard field-sampling protocols (distance sampling). We also explored the complementarity of these 2 approaches. LEK provided high-quality and low-cost information about both distribution and abundance of T. graeca . Interviews with shepherds yielded abundance estimates in a much wider range than linear transects, which only detected the species in the upper two-thirds of its abundance range. Abundance estimates from both methodologies showed a close relationship. Analysis of confidence intervals indicated local knowledge could be used to estimate mean local abundances and to detect mean population trends. A cost analysis determined that the information derived from LEK was 100 times cheaper than that obtained through linear-transect surveys. Our results should further the use of LEK as a standard tool for sampling the quantitative abundance of a great variety of taxa, particularly when population densities are low and traditional sampling methods are expensive or difficult to implement.  相似文献   
169.
There has been much recent interest in using local knowledge and expert opinion for conservation planning, particularly for hard‐to‐detect species. Although it is possible to ask for direct estimation of quantities such as population size, relative abundance is easier to estimate. However, an expert's knowledge is often geographically restricted relative to the area of interest. Combining (or aggregating) experts’ assessments of relative abundance is difficult when each expert only knows a part of the area of interest. We used Google's PageRank algorithm to aggregate ranked abundance scores elicited from local experts through a rapid rural‐appraisal method. We applied this technique to conservation planning for the saola (Pseudoryx nghetinhensis), a poorly known bovid. Near a priority landscape for the species, composed of 3 contiguous protected areas, we asked groups of local people to indicate relative abundances of saola and other species by placing beans on community maps. For each village, we used this information to rank areas within the knowledge area of that village for saola abundance. We used simulations to compare alternative methods to aggregate the rankings from the different villages. The best‐performing method was then used to produce a single map of relative abundance across the entire landscape, an area larger than that known to any one village. This map has informed prioritization of surveys and conservation action in the continued absence of direct information about the saola.  相似文献   
170.
Graduate education programs in conservation science generally focus on disciplinary training and discipline‐specific research skills. However, nonacademic conservation professionals often require an additional suite of skills. This discrepancy between academic training and professional needs can make it difficult for graduate students to identify the skills and experiences that will best prepare them for the conservation job market. We analyzed job advertisements for conservation‐science positions and interviewed conservation professionals with experience hiring early‐career conservation scientists to determine what skills employers of conservation professionals seek; whether the relative importance of skills varies by job sector (government, nonprofit, and private); and how graduate students interested in careers in conservation science might signal competency in key skills to potential employers. In job advertisements, disciplinary, interpersonal, and project‐management skills were in the top 5 skills mentioned across all job sectors. Employers’ needs for additional skills, like program leadership, conflict resolution and negotiation, and technical and information technology skills, varied across sectors. Our interview results demonstrated that some skills are best signaled to employers via experiences obtained outside thesis or dissertation work. Our findings suggest that graduate students who wish to be competitive in the conservation job market can benefit by gaining skills identified as important to the job sector in which they hope to work and should not necessarily expect to be competent in these skills simply by completing their chosen degree path. Guía para el Estudiante de Grado de las Habilidades Necesarias para Carreras de Conservación Académicas  相似文献   
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