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1.
Understanding implications of consumer behavior for wildlife farming and sustainable wildlife trade 下载免费PDF全文
A. Nuno J. M. Blumenthal T. J. Austin J. Bothwell G. Ebanks‐Petrie B. J. Godley A. C. Broderick 《Conservation biology》2018,32(2):390-400
Unsustainable wildlife trade affects biodiversity and the livelihoods of communities dependent upon those resources. Wildlife farming has been proposed to promote sustainable trade, but characterizing markets and understanding consumer behavior remain neglected but essential steps in the design and evaluation of such operations. We used sea turtle trade in the Cayman Islands, where turtles have been farm raised for human consumption for almost 50 years, as a case study to explore consumer preferences toward wild‐sourced (illegal) and farmed (legal) products and potential conservation implications. Combining methods innovatively (including indirect questioning and choice experiments), we conducted a nationwide trade assessment through in‐person interviews from September to December 2014. Households were randomly selected using disproportionate stratified sampling, and responses were weighted based on district population size. We approached 597 individuals, of which 37 (6.2%) refused to participate. Although 30% of households had consumed turtle in the previous 12 months, the purchase and consumption of wild products was rare (e.g., 64–742 resident households consumed wild turtle meat [i.e., 0.3–3.5% of households] but represented a large threat to wild turtles in the area due to their reduced populations). Differences among groups of consumers were marked, as identified through choice experiments, and price and source of product played important roles in their decisions. Despite the long‐term practice of farming turtles, 13.5% of consumers showed a strong preference for wild products, which demonstrates the limitations of wildlife farming as a single tool for sustainable wildlife trade. By using a combination of indirect questioning, choice experiments, and sales data to investigate demand for wildlife products, we obtained insights about consumer behavior that can be used to develop conservation‐demand‐focused initiatives. Lack of data from long‐term social–ecological assessments hinders the evaluation of and learning from wildlife farming. This information is key to understanding under which conditions different interventions (e.g., bans, wildlife farming, social marketing) are likely to succeed. 相似文献
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Mangrove Mapping Using Landsat Imagery and Aerial Photographs: Kemaman District, Terengganu, Malaysia 总被引:2,自引:0,他引:2
I. Sulong H. Mohd-Lokman K. Mohd-Tarmizi A. Ismail 《Environment, Development and Sustainability》2002,4(2):135-152
Classification and distribution of mangrove vegetation are vital information for the proper development of a mangrove management plan. In this study, classification for the mangroves of the district of Kemaman were done using both 1 : 5000 aerial photographs and Landsat TM imageries. The coverage by aerial photographs is limited to the coastal and estuarine areas only. Thus, for areas further upstream of the aerial photo coverage, Landsat TM imageries were used. Analysis of aerial photographs and remote sensing images revealed that the mangroves of Kemaman could be classified into 14 different classes of vegetation. All the 14 classes were identified from areas covered by the aerial photographs. For areas covered by the Landsat images only 7 classes of vegetation were identified. The accuracy for aerial photograph and Landsat images are 91.2% and 87.8%, respectively. It can be concluded that although both techniques are useful in determining the mangrove vegetation classes, the large 1 : 5000 aerial photographs are more accurate and provided more detailed information comparatively. 相似文献
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本文构建S-T模型,运用集对分析理论(set pair analysis)构建基本模型,采用层次分析法并参考毒性当量因子确定各指标权重,应用三角模糊数(triangular fuzzy number)对差异度系数进行改进,基于加拿大沉积物环境质量标准,对沉积物中多环芳烃进行生态风险分级评价.结果表明,该模型考虑到化合物之间的相互作用因素并做模糊处理,对差异度系数进行改进体现沉积物中多环芳烃生态风险等级标准的模糊性,为持久性有机污染物生态风险分级评价提供了一种简便客观有效的方法. 相似文献
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Bioindicator organisms: Heavy metal pollution evaluation in the Ionian Sea (Mediterranean Sea—Italy)
Trace metal concentrations of mercury, cadmium, lead and chromium in Patella caerulea, and Mullus barbatus were investigated to provide information on pollution of Ionian Sea, since these metals have the highest toxic potential. High chromium levels (0.47–0.97 g g–1 ww) were registered in limpet samples collected from two station near the Gulf of Taranto, while elevated concentration of mercury (0.31–1.50 g g–1 ww) were found in mullet specimens from Sicily. The metal concentrations recorded at the clean stations may be considered as useful background levels to which to refer for comparison within the Mediterranean area. On the contrary, the high levels of chromium and mercury found respectively in the areas near the Gulf of Taranto and at Capo Passero being of concern in terms of environmental health need frequent monitoring. 相似文献
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辽东湾海冰晶体结构及其内部叶绿素的初步研究 总被引:6,自引:0,他引:6
本文介绍了1996年冬季首次辽东湾生态环境调查中的海洋背景条件。扼要地阐述了辽东湾海冰一般概况,分析辽东湾冰样晶体结构、存储条件及其与冰内和冰下海水叶绿素之间的关系。辽东湾冰内叶绿素符合其它结冰海区的一般规律。根据辽东湾冰层底部实测盐度变化规律阐明海冰对冰下海水营养盐的贡献。最后对深入开展结冰海区生态环境调查工作的技术、侧重点和意义做了讨论。 相似文献
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探讨影响赤潮的物理因子及其预报 总被引:15,自引:2,他引:15
通过多年对广东沿海港湾赤潮发生机理的探讨 ,归纳出引发赤潮的主要物理因子 ,并深入研究潮汐变化与赤潮形成的关系。作者认为在沿海一些半封闭的海湾 ,在月赤纬偏小期间发生大潮易引发赤潮。大亚湾澳头水域 4~ 5月份大潮后多呈现不正规全日潮 ,易出现赤潮生物高峰期 ,较明显的赤潮从发生至消退的全过程往往跨越一个潮水期。根据实践经验总结 ,作者提出利用潮汐变化规律对大亚湾澳头水域 2 0 0 1年 5月份可能出现的赤潮初始阶段作尝试性预测 ,并在赤潮初始阶段通过对水域的浮游生物优势种和当地天气的变化趋势加强观测、研究 ,希望能对赤潮暴发作出较准确的预报。 相似文献
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