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71.
With the potential expansion of forest conservation programs spurred by climate-change agreements, there is a need to measure the extent to which such programs achieve their intended results. Conventional methods for evaluating conservation impact tend to be biased because they do not compare like areas or account for spatial relations. We assessed the effect of a conservation initiative that combined designation of protected areas with payments for environmental services to conserve over wintering habitat for the monarch butterfly (Danaus plexippus) in Mexico. To do so, we used a spatial-matching estimator that matches covariates among polygons and their neighbors. We measured avoided forest loss (avoided disturbance and deforestation) by comparing forest cover on protected and unprotected lands that were similar in terms of accessibility, governance, and forest type. Whereas conventional estimates of avoided forest loss suggest that conservation initiatives did not protect forest cover, we found evidence that the conservation measures are preserving forest cover. We found that the conservation measures protected between 200 ha and 710 ha (3-16%) of forest that is high-quality habitat for monarch butterflies, but had a smaller effect on total forest cover, preserving between 0 ha and 200 ha (0-2.5%) of forest with canopy cover >70%. We suggest that future estimates of avoided forest loss be analyzed spatially to account for how forest loss occurs across the landscape. Given the forthcoming demand from donors and carbon financiers for estimates of avoided forest loss, we anticipate our methods and results will contribute to future studies that estimate the outcome of conservation efforts. 相似文献
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Emily Boyd Nate Hultman J. Timmons Roberts Esteve Corbera John Cole Alex Bozmoski Johannes Ebeling Robert Tippman Philip Mann Katrina Brown Diana M. Liverman 《Environmental Science & Policy》2009,12(7):820-831
The Clean Development Mechanism (CDM) has successfully demonstrated that market-based mechanisms can achieve some cost effective emissions reductions in developing countries. However the distribution of CDM projects has been extremely uneven across countries and regions, and a few technologies and sectors have dominated the early stages of CDM experience. This has caused some to question whether the CDM has fallen short of its potential in contributing to sustainable development. We review the broad patterns of CDM project approvals and evaluate 10 CDM projects according to their sustainability benefits. The difficulty of defining “sustainable development” and the process of defining criteria by individual non-Annex 1 governments has meant that sustainable development concerns have been marginalized in some countries. Given these observed limitations, we present possible CDM policy futures, focusing on the main proposals for a post-2012 climate regime. Five options for enhancing the sustainable development benefits in the CDM are discussed, including proactive approaches to favour eligibility of emission reduction projects which ensure such co-benefits. 相似文献
76.
Mann RE Adlaf E Zhao J Stoduto G Ialomiteanu A Smart RG Asbridge M 《Journal of Safety Research》2007,38(6):669-674
PROBLEM: This study examines the relationships between collision involvement and several measures of cannabis use, including driving after using cannabis, among drivers, based on a population survey of Ontario adults in 2002 and 2003. METHOD: Logistic regression analyses examined self-reported collision involvement in the last 12 months by lifetime use of cannabis, past year use of cannabis, and past year driving after using cannabis, while controlling for demographic characteristics. RESULTS: We found that the odds of reporting collision involvement was significantly higher among cannabis users, and among those who reported driving after cannabis use. Some evidence for a dose-response relationship was seen as well. DISCUSSION: Cannabis users and people who report driving after cannabis use are also more likely to report being involved in a collision in the past year. These observations suggest that collision prevention efforts could be aimed at these groups. Additional work to determine the causal pathways involved in the relationships observed here is needed. IMPACT ON INDUSTRY: None. 相似文献
77.
环境雌激素玉米赤霉烯酮(ZEN)的生态安全性近年来受到越来越多的关注。以秀丽隐杆线虫(Caenorhabdites elegans)为模式生物研究ZEN对线虫的生殖损伤作用。在DIC显微镜下观察,48 h暴露后与对照组相比,暴露组线虫性腺臂明显萎缩,卵母细胞数目和大小均受到显著影响(P0.01),并且可见部分暴露组线虫产卵器严重畸形。这均表明ZEN暴露对秀丽隐杆线虫生殖系统的发育和功能可产生损害作用。 相似文献
78.
由于毒性评估项目很难与日渐增长的需要测试的污染物保持同步,所以较难将关注点集中在影响水生生态系统的最为生物相关的污染物上。由于评估潜在毒性污染物所造成的生物影响已被证明是有效的,内生性代谢物的研究(代谢组学)对于剔除那些较低可能造成生物影响的污染物或许有一定帮助,从而找出生物重要性最高的污染物。本研究在北美五大湖流域的18个地点针对置于笼中的黑头软口鲦(Pimephales promelas)进行实验。我们测定了水体温度和水样中的污染物浓度(目标污染物132种,检出86种),并使用1H-NMR谱测量了肝极性提取物中的内生性代谢物。利用偏最小二乘法回归来比对内生性代谢物的相对丰度与污染物浓度和环境温度。结果表明内生性极性代谢物的指标与最多49种污染物存在共同变化。因此我们认为至多52%的检出污染物与内生性代谢物变化的共同变化不显著,表明这些污染物很可能不会在这些地点造成可以检测到的影响。这是通过缩短对于实验地点有着潜在影响的污染物列表从而扫描出检出污染物生物相关性的第一步。类似的信息有助于风险评估者区分不同污染物的重要性并将重点毒性测试放在最为生物相关的污染物上。
精选自Nicol Janecko, Lucie Pokludova, Jana Blahova, Zdenka Svobodova, Ivan Literak. Linking field-based metabolomics and chemical analyses to prioritize contaminants of emerging concern in the Great Lakes basin. Environmental Toxicology and Chemistry: Volume 35, Issue 10, pages 2493–2502, October 2016.
DOI: 10.1002/etc.3409
详情请见http://onlinelibrary.wiley.com/doi/10.1002/etc.3409/full 相似文献
79.
The Belgian Coastal Atlas was first published in hardback in 2004, with no intention to move towards a web version. The many
requests for maps encouraged the developers to launch a web-based atlas in 2005. The interactive-nature of the maps was kept
simple and the look of the maps was considered more important than the possibilities that GIS applications offered. Three
years on, the Coordination Centre on ICZM would like to move from the more or less static web atlas to an interactive data-driven
atlas, where sustainability indicators for the coast play a prominent role. The final product will be a policy supporting
tool that will back the ICZM process for a wide range of coastal actors, planners and managers. 相似文献
80.
Thomas Artiss Wesley M. Hochachka Kathy Martin 《Behavioral ecology and sociobiology》1999,46(6):429-434
For several species of birds, high rates of male vigilance are correlated with high rates of female foraging. This relationship
is thought to ultimately result in higher reproductive success for females paired with highly vigilant males. However, previous
research has not examined the behavioural mechanism that produces the correlation between male vigilance and rates of female
foraging. Foraging females may take advantage of vigilance that males are using for other purposes. Alternatively, the purpose
of male vigilance may be to increase females' ability to forage. We examined these alternatives by testing whether vigilance
preceded or followed bouts of female foraging more often than would occur by chance alone, using simultaneous behaviour observations
of pre-incubation pairs of white-tailed ptarmigan (Lagopus leucurus). Our results indicate that each member of a pair may influence the behaviour of the other. Females were more likely to initiate
foraging bouts after males became vigilant than if their mate remained non-vigilant. Moreover, non-vigilant males were more
likely to become vigilant if their mate was foraging than if she was engaged in some other activity. Despite the possibility
that a sexual conflict exists as each member of a pair attempts to maximize its fitness, both sexes behave as though a major
role of male vigilance is to enhance female foraging opportunities.
Received: 3 May 1999 / Received in revised form: 14 June 1999 / Accepted: 16 June 1999 相似文献