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71.
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
72.
When three per cent may not be three per cent; device-equipped seabirds experience variable flight constraints 总被引:1,自引:1,他引:0
Current guidelines for instrumenting birds state that external devices should not exceed 3–5% of the birds’ body mass; however,
the energetic consequences of carrying any given device mass are likely to vary according to the morphology and ecology of
the species concerned. We used a freeware program to estimate the mechanical power requirements of flight at the minimum power
speed for 80 species of flying seabird from 8 major groups with payloads of increasing mass. Devices representing 3% of the
bird’s body mass resulted in an increase in energy expenditure for flight ranging from 4.67 to 5.71% without accounting for
the increase in body drag coefficient associated with external devices. This effect differed within and between seabird lineages
with members of the Alcidae and Phalacrocoracidae experiencing the highest energetic costs of any increase in device mass.
We propose that device effects on seabirds could be further reduced through consideration of species-specific effects of added
payload and drag. 相似文献
73.
Both birds and bats are important insect predators in tropical systems. However, the relative influence of birds and bats on insect populations and their indirect effects on leaf damage have not previously been investigated in tropical forest restoration sites. Leaf damage by herbivorous insects can negatively affect the growth and survival of tropical plants and thus can influence the success of tropical forest restoration efforts. We used an exclosure experiment to examine the top-down effects of birds and bats on insects and leaf damage in a large-scale forest restoration experiment. Given the potential influence of tree planting design on bird and bat abundances, we also investigated planting design effects on bird and bat insectivory and leaf damage. The experiment included two planting treatment plots: islands, where trees were planted in patches, and plantations, where trees were planted in rows to create continuous cover. In both types of plots, insect biomass was highest on tree branches where both birds and bats were excluded from foraging and lowest on branches without exclosures where both birds and bats were present. In the island plots, birds and bats had approximately equal impacts on insect populations, while in plantations bats appeared to have a slightly stronger effect on insects than did birds. In plantations, the levels of leaf damage were higher on branches where birds and bats were excluded than on branches where both had access. In island plots, no significant differences in leaf damage were found between exclosure treatments although potential patterns were in the same direction as in the plantations. Our results suggest that both birds and bats play important roles as top predators in restoration systems by reducing herbivorous insects and their damage to planted trees. Tropical restoration projects should include efforts to attract and provide suitable habitat for birds and bats, given their demonstrated ecological importance. 相似文献
74.
Alexander D. M. Wilson Emily M. Whattam Rachel Bennett Laksanavadee Visanuvimol Chris Lauzon Susan M. Bertram 《Behavioral ecology and sociobiology》2010,64(5):703-715
Recently, there has been increasing interest in behavioral syndrome research across a range of taxa. Behavioral syndromes
are suites of correlated behaviors that are expressed either within a given behavioral context (e.g., mating) or between different
contexts (e.g., foraging and mating). Syndrome research holds profound implications for animal behavior as it promotes a holistic
view in which seemingly autonomous behaviors may not evolve independently, but as a “suite” or “package.” We tested whether
laboratory-reared male and female European house crickets, Acheta domesticus, exhibited behavioral syndromes by quantifying individual differences in activity, exploration, mate attraction, aggressiveness,
and antipredator behavior. To our knowledge, our study is the first to consider such a breadth of behavioral traits in one
organism using the syndrome framework. We found positive correlations across mating, exploratory, and antipredatory contexts,
but not aggression and general activity. These behavioral differences were not correlated with body size or condition, although
age explained some of the variation in motivation to mate. We suggest that these across-context correlations represent a boldness
syndrome as individual risk-taking and exploration was central to across-context mating and antipredation correlations in
both sexes. 相似文献
75.
Market-based conservation mechanisms are designed to facilitate the mitigation of harm to and conservation of habitats and biodiversity. Their potential is partly hindered, however, by the quantification tools used to assess habitat quality and functionality. Of specific concern are the lack of transparency and standardization in tool development and gaps in tool availability. To address these issues, we collected information via internet and literature searchers and through conversations with tool developers and users on tools used in U.S. conservation mechanisms, such as payments for ecosystem services (PES) and ecolabel programs, conservation banking, and habitat exchanges. We summarized information about tools and explored trends among and within mechanisms based on criteria detailing geographic, ecological, and technical features of tools. We identified 69 tools that assessed at least 34 species and 39 habitat types. Where tools reported pricing, 98% were freely available. More tools were applied to states along the U.S. West Coast than elsewhere, and the level of tool transferability varied markedly among mechanisms. Tools most often incorporated conditions at numerous spatial scales, frequently addressed multiple risks to site viability, and required 1–83 data inputs. Most tools required a moderate or greater level of user skill. Average tool-complexity estimates were similar among all mechanisms except PES programs. Our results illustrate the diversity among tools in their ecological features, data needs, and geographic application, supporting concerns about a lack of standardization. However, consistency among tools in user skill requirements, incorporation of multiple spatial scales, and complexity highlight important commonalities that could serve as a starting point for establishing more standardized tool development and feature-incorporation processes. Greater standardization in tool design may expand market participation and facilitate a needed assessment of the effectiveness of market-based conservation. 相似文献
76.
McFarland CA Quinn MJ Boyce J LaFiandra EM Bazar MA Talent LG Johnson MS 《Environmental pollution (Barking, Essex : 1987)》2011,159(2):466-473
The compound 2-amino-4,6-dinitrotoluene (2A-DNT) was evaluated under laboratory conditions in the Western fence lizard (Sceloporus occidentalis) to assess the potential for reptile toxicity. Oral LD50 values were 1406 and 1867 mg/kg for male and female lizards, respectively. Based on responses from a 14-day subacute study, a 60-day subchronic experiment followed where lizards were orally dosed at 0, 5, 15, 20, 25, 30 mg/kg-d. At day 60, number of days and survivors, food consumption, and change in body weight were inversely related to dose. Signs of toxicity were characterized by anorexia and generalized cachexia. Significant adverse histopathology was observed in hepatic tissue at ≥15 mg/kg-d, consistent with hepatocellular transdifferentiation. Based on survival, loss of body weight, diminished food intake, changes in liver, kidney, and testes, and increased blood urea nitrogen, these data suggest a LOAEL of 15 mg/kg-d and a NOAEL of 5 mg/kg-d in S. occidentalis. 相似文献
77.
James J. Huntzicker Emily K. Heyerdahl Stephen R. McDow John A. Rau Wayne H. Griest Carolyn S. MacDougall 《Journal of the Air & Waste Management Association (1995)》2013,63(6):705-709
Organic and elemental carbon and a number of carboxylic acids and n-alkanes were measured in aerosol samples collected at three sites in the Ohio River Valley between October 1980 and August 1981. Approximately 100 filters were analyzed for organic and elemental carbon for each site. For the 11-month period organic and elemental carbon comprised about 19 percent of the total aerosol mass with about two-thirds of the carbon as organic. Regression analysis showed that the principal source of organic carbon was combustion. The measurements of the specific organic compounds indicated a weak biogenic component to the organic aerosol. 相似文献
78.
David Blodgett Emily Read Jessica Lucido Tad Slawecki Dwane Young 《Journal of the American Water Resources Association》2016,52(4):845-858
Improving access to data and fostering open exchange of water information is foundational to solving water resources issues. In this vein, the Department of the Interior's Assistant Secretary for Water and Science put forward the charge to undertake an Open Water Data Initiative (OWDI) that would prioritize and accelerate work toward better water data infrastructure. The goal of the OWDI is to build out the Open Water Web (OWW). We therefore considered the OWW in terms of four conceptual functions: water data cataloging, water data as a service, enriching water data, and community for water data. To describe the current state of the OWW and identify areas needing improvement, we conducted an analysis of existing systems using a standard model for describing distributed systems and their business requirements. Our analysis considered three OWDI‐focused use cases—flooding, drought, and contaminant transport—and then examined the landscape of other existing applications that support the Open Water Web. The analysis, which includes a discussion of observed successful practices of cataloging, serving, enriching, and building community around water resources data, demonstrates that we have made significant progress toward the needed infrastructure, although challenges remain. The further development of the OWW can be greatly informed by the interpretation and findings of our analysis. 相似文献
79.
80.
Hoang TC Rogevich EC Rand GM Gardinali PR Frakes RA Bargar TA 《Environmental pollution (Barking, Essex : 1987)》2008,154(2):338-347
Copper (Cu) desorption and toxicity to the Florida apple snail were investigated from soils obtained from agricultural sites acquired under the Comprehensive Everglades Restoration Plan. Copper concentrations in 11 flooded soils ranged from 5 to 234 mg/kg on day 0 and from 6.2 to 204 mg/kg on day 28 (steady-state). The steady-state Cu concentration in overlying water ranged from 9.1 to 308.2 microg/L. In a 28-d growth study, high mortality in snails occurred within 9 to 16 d in two of three soil treatments tested. Growth of apple snails over 28 d was affected by Cu in these two treatments. Tissue Cu concentrations by day 14 were 12-23-fold higher in snails exposed to the three soil treatments compared to controls. The endangered Florida snail kite and its main food source, the Florida apple snail, may be at risk from Cu exposure in these managed agricultural soil-water ecosystems. 相似文献