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41.
Cátia Canteiro Laísa Barcelos Fabiana Filardi Rafaela Forzza Laura Green João Lanna Paula Leitman William Milliken Marli Pires Morim Kristina Patmore Sarah Phillips Barnaby Walker Marie-Hélène Weech Eimear Nic Lughadha 《Conservation biology》2019,33(3):523-533
Herbarium specimens are increasingly recognized as an important resource for conservation science and virtual herbaria are making specimens freely available to a wider range of users than ever before. Few virtual herbaria are designed with conservation use as a primary driver. Exceptionally, Brazil's Reflora Virtual Herbarium (RVH) was created to increase knowledge and conservation of the Brazilian flora. The RVH is closely integrated with the Flora of Brazil 2020 platform on which Brazil's new national Flora is under construction. Both resources are accessible via the Reflora home page and thousands of users move seamlessly between these Reflora resources. To understand how the Reflora resources are currently used and their impact on conservation science, we conducted a literature review and an online survey. We searched for publications of studies in which Reflora resources were used and publications resulting from Brazilian researchers who were part of Reflora's research and mobility program. The survey contained multiple choice questions and questions that required a written response. We targeted Reflora webpage visitors with the survey to capture a wider range of Reflora users than the literature review. Reflora resources were used for a variety of conservation-relevant purposes. Half the 806 scientific publications in which Reflora was cited and 81% of the 1069 survey respondents accessing Reflora resources mentioned conservation-relevant research outputs. Most conservation-relevant uses of the Reflora resources in scientific publications were research rather than implementation focused. The survey of Reflora users showed conservation uses and impacts of virtual herbaria were more numerous and diverse than the uses captured in the literature review. Virtual herbaria are vital resources for conservation science, but they must document use and impacts more comprehensively to ensure sustainability. 相似文献
42.
Policies for conservation outside protected areas, such as those designed to address the decline in Australian mammals, will not result in net improvements unless they address barriers to proenvironmental behavior. We used a mixed‐methods approach to explore potential value‐action gaps (disconnects between values and subsequent action) for small mammal conservation behaviors among pastoralists in dryland Australia. Using semistructured surveys and open‐ended interviews (n = 43), we explored values toward small mammals; uptake of a range of current and intended actions that may provide benefit to small mammals; and potential perceived barriers to their uptake. Pastoralists assigned great conservation value to small mammals; over 80% (n = 36) agreed to strongly agreed that small mammals on their property were important. These values did not translate into stated willingness to engage in voluntary cessation of wild‐dog control (r2 = 0.187, p = 0.142, n = 43). However, assigning great conservation value to small mammals was strongly related to stated voluntary willingness to engage in the proenvironmental behavior most likely to result in benefits to small mammals: cat and fox control (r2 = 0.558, p = 0.000, n = 43). There was no significant difference between stated voluntarily and incentivized willingness to engage in cat and fox control (p = 0.862, n = 43). The high levels of willingness to engage in voluntary cat and fox control highlight a potential entry point for addressing Australia's mammal declines because the engagement of pastoralists in conservation programs targeting cat and fox control is unlikely to be prevented by attitudinal constraints. Qualitative data suggest there is likely a subpopulation of pastoralists who value small mammals but do not wish to engage in formal conservation programs due to relational barriers with potential implementers. A long‐term commitment to engagement with pastoralists by implementers will thus be necessary for conservation success. On‐property cat and fox control programs that build and leverage trust, shared goals, collaboration, and shared learning experiences between stakeholders and that explicitly recognize the complexity of small mammal dynamics and the property‐level ecological knowledge of pastoralists are more likely to gain traction. 相似文献
43.
农村环境问题是中国环境保护面临的又一严峻挑战,深入探讨其成因是解决问题的关键.中国农村环境问题是多方面因素共同作用的结果,但其根本是城乡居民经济水平差距的日趋扩大使农村发展重经济轻环境、城乡环境权益的不平等使农村承担城市转嫁污染而得不到补偿,以及城乡统筹发展过程中未真正将农村与城市平等对待的偏差. 相似文献
44.
Abstract: Quantifying the extent to which existing reserves meet conservation objectives and identifying gaps in coverage are vital to developing systematic protected‐area networks. Despite widespread recognition of the Philippines as a global priority for marine conservation, limited work has been undertaken to evaluate the conservation effectiveness of existing marine protected areas (MPAs). Targets for MPA coverage in the Philippines have been specified in the 1998 Fisheries Code legislation, which calls for 15% of coastal municipal waters (within 15 km of the coastline) to be protected within no‐take MPAs, and the Philippine Marine Sanctuary Strategy (2004), which aims to protect 10% of coral reef area in no‐take MPAs by 2020. We used a newly compiled database of nearly 1000 MPAs to measure progress toward these targets. We evaluated conservation effectiveness of MPAs in two ways. First, we determined the degree to which marine bioregions and conservation priority areas are represented within existing MPAs. Second, we assessed the size and spacing patterns of reserves in terms of best‐practice recommendations. We found that the current extent and distribution of MPAs does not adequately represent biodiversity. At present just 0.5% of municipal waters and 2.7–3.4% of coral reef area in the Philippines are protected in no‐take MPAs. Moreover, 85% of no‐take area is in just two sites; 90% of MPAs are <1 km2. Nevertheless, distances between existing MPAs should ensure larval connectivity between them, providing opportunities to develop regional‐scale MPA networks. Despite the considerable success of community‐based approaches to MPA implementation in the Philippines, this strategy will not be sufficient to meet conservation targets, even under a best‐case scenario for future MPA establishment. We recommend that implementation of community‐based MPAs be supplemented by designation of additional large no‐take areas specifically located to address conservation targets. 相似文献
45.
分析探讨了浙江鄞县42级地震及历史上浙北中强震前的地震空区现象,认为孕震空区可能是浙北中等及中强震的中期前兆,并提出浙北孕震空区的特征及判别方法。 相似文献
46.
为了分析轨缝值与行车速度对车辆通过钢轨接头时产生的振动与噪声的影响程度,利用有限元方法,建立了车辆—轨道垂向耦合动力计算模型;该模型的车辆采用整车模型,共10个自由度;轨道结构采用3层弹性点支承有限长欧拉梁模型,共402个自由度;系统的激励大小可由轨缝值和行车速度推导出来,并运用赫兹非线性接触理论计算轮轨之间的相互作用力。采用该模型,结合快速显式迭代积分法和MATLAB6.5强大的矩阵分析功能,对不同轨缝值和车辆行驶速度条件下钢轨接头的动力响应进行了计算,为减振降噪提供理论依据。 相似文献
47.
均等指数和两极化指数建立与比较 总被引:1,自引:0,他引:1
王力 《中国人口.资源与环境》2012,22(1):149-154
在基尼系数衡量收入差距存在一定缺陷和我国收入两极化概念不清楚的情况下,本文重点对基尼系数与两极分化的涵义进行了剖析,指出了两个概念的本质与它们之间的联系、区别。对以后的收入差距测量有一定的指导意义。基尼系数反映了所有个体偏离总体的程度,两极化指数反映二大组之间差异情况。在前人测量收入差距方法基础上构造两极分化指数I。结合中国和部分其它国家的数据,测量了三个指数并进行了比较分析,结果表明:三个指数高度相关,在一般情况下均等指数、基尼系数和两极分化指数都能大致反映收入差距情况。对组间、组内差距处理方法不同是基尼系数(均等指数)与两极分化指数最根本的区别。构造的两极分化指数具有直观、易于理解、意义明确、计算简单等诸多优点。因此在测量收入差距时,倡导优先使用均等指数。在测量只有二等分组构成总体的收入差距时,优先选择两极分化指数。实际研究中,可以根据研究的问题,合理地选择基尼系数,均等指数,两极分化指数从事相关研究。 相似文献
48.
Kaufman MM 《Environmental management》2000,26(1):89-97
/ To test the effectiveness of Michigan's soil erosion control law, 30 construction sites were evaluated in the east-central part of the state. The analytical framework lumped nine best management practices (BMPs) most closely related to the law into three categories: slope stabilization, soil stabilization, and water management. All sites were in the land clearing or foundation/framing stage of construction and were evaluated within 2 days after a rainfall event. Only four of the sites performed above the mean of the scoring scale, with the categorical scoring of BMPs indicating the worst performance for slope stabilization measures. The poor results suggest a failure to integrate scientific knowledge of erosion control with policy. A fundamental problem is the lack of basic site data on soil, topography, and hydrology, resulting in the incorrect application of BMPs, such as staging, filter fences, and berms. The current institutional framework for soil erosion control also provides disincentives to mitigate local erosion problems. 相似文献
49.
关于地区绿色距离和绿色贡献的变迁分析 总被引:11,自引:1,他引:10
全面建设小康社会必须摒弃“高消耗、高污染、低产出”的模式,树立和落实科学发展观,走绿色发展道路。该文以万元GDP能源消耗、水资源消耗、COD排放、SO2排放4个指标为基础,建立体现经济与环境协调发展的绿色距离和绿色贡献2个综合性指标,以生态省和生态市捐应指标为标准,分析了我国大陆地区各省份对应4个指标的绿色距离和绿色贡献现状。比较分析表明:经济发达地区如北京、上海、江苏、浙江等省份开始向“绿色经济”变迁;经济中游地区如辽宁、河北、湖北、安徽、吉林、黑龙江等省份则处于走出“黑色经济”发展的边缘并向“绿色经济”转化的阶段;其他地区则基本上处于“黑色经济”发展阶段,不仅绿色距离大,而且绿色贡献均小于1。 相似文献
50.