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221.
Matthew J. Colloff Sandra Lavorel Lorrae E. van Kerkhoff Carina A. Wyborn Ioan Fazey Russell Gorddard Georgina M. Mace Wendy B. Foden Michael Dunlop I. Colin Prentice John Crowley Paul Leadley Patrick Degeorges 《Conservation biology》2017,31(5):1008-1017
We examine issues to consider when reframing conservation science and practice in the context of global change. New framings of the links between ecosystems and society are emerging that are changing peoples’ values and expectations of nature, resulting in plural perspectives on conservation. Reframing conservation for global change can thus be regarded as a stage in the evolving relationship between people and nature rather than some recent trend. New models of how conservation links with transformative adaptation include how decision contexts for conservation can be reframed and integrated with an adaptation pathways approach to create new options for global‐change‐ready conservation. New relationships for conservation science and governance include coproduction of knowledge that supports social learning. New processes for implementing adaptation for conservation outcomes include deliberate practices used to develop new strategies, shift world views, work with conflict, address power and intergenerational equity in decisions, and build consciousness and creativity that empower agents to act. We argue that reframing conservation for global change requires scientists and practitioners to implement approaches unconstrained by discipline and sectoral boundaries, geopolitical polarities, or technical problematization. We consider a stronger focus on inclusive creation of knowledge and the interaction of this knowledge with societal values and rules is likely to result in conservation science and practice that meets the challenges of a postnormal world. 相似文献
222.
Establishing protected areas (PAs) is an essential strategy to reduce biodiversity loss. However, many PAs do not provide adequate protection due to poor funding, inadequate staffing and equipment, and ineffective management. As part of China's recent economic growth, the Chinese government has significantly increased investment in nature reserves over the past 20 years, providing a unique opportunity to evaluate whether PAs can protect threatened species effectively. We compiled data from published literature on populations of gibbons (Hylobatidae), a threatened taxon with cultural significance, that occurred in Chinese reserves after 1980. We evaluated the ability of these PAs to maintain gibbon habitat and populations by comparing forest cover and human disturbance between reserves and their surrounding areas and modeling the impact of reserve characteristics on gibbon population trends. We also assessed the perspective of reserve staff concerning PA management effectiveness through an online survey. Reserves effectively protected gibbon habitat by reducing forest loss and human disturbance; however, half the reserves lost their gibbon populations since being established. Gibbons were more likely to survive in reserves established more recently, at higher elevation, with less forest loss and lower human impact, and that have been relatively well studied. A larger initial population size in the 1980s was positively associated with gibbon persistence. Although staff of all reserves reported increased investment and improved management over the past 20–30 years, no relationship was found between management effectiveness and gibbon population trends. We suggest early and emphatic intervention is critical to stop population decline and prevent extinction. 相似文献
223.
Feasibility of using high‐resolution satellite imagery to assess vertebrate wildlife populations
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Although remote sensing has been used for >40 years to learn about Earth, use of very high‐resolution satellite imagery (VHR) (<1‐m resolution) has become more widespread over the past decade for studying wildlife. As image resolution increases, there is a need to understand the capabilities and limitations of this exciting new path in wildlife research. We reviewed studies that used VHR to examine remote populations of wildlife. We then determined characteristics of the landscape and the life history of species that made the studies amenable to use of satellite imagery and developed a list of criteria necessary for appropriate use of VHR in wildlife research. From 14 representative articles, we determined 3 primary criteria that must be met for a system and species to be appropriately studied with VHR: open landscape, target organism's color contrasts with the landscape, and target organism is of detectable size. Habitat association, temporal exclusivity, coloniality, landscape differentiation, and ground truthing increase the utility of VHR for wildlife research. There is an immediate need for VHR imagery in conservation research, particularly in remote areas of developing countries, where research can be difficult. For wildlife researchers interested in but unfamiliar with remote sensing resources and tools, understanding capabilities and current limitations of VHR imagery is critical to its use as a conservation and wildlife research tool. 相似文献
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226.
R.J. Thompson T. B. McMullen G.B. Morgan 《Journal of the Air & Waste Management Association (1995)》2013,63(8):484-487
The body of the information presented in this paper is of general interest to those concerned with air quality. This paper reports data for ambient atmospheric concentrations of water-soluble fluorides determined in samples of suspended particulate matter collected on glass-fiber filters by the National Air Surveillance Network. Data for over 12,000 samples collected in calendar years 1966, 1967, and 1968 are examined. The purpose of the examination of the data is to give an estimation of current air quality with respect to fluoride content. The samples are extracted with pure boiling water, and the fluoride concentration of the extracts measured using a fluoride-ion selective electrode. The data engendered are tabulated on an annual basis, and a table is presented summarizing the results. Comparative data will be presented showing the distribution of urban and non-urban stations that exhibit various specified fluoride levels. The results show that the fluoride content in the majority of the samples is below the minimum detectable amount of 0.05 µgF/m3. Conclusions that can be drawn include the observations that: few of the urban samples contain over 1.00 µg/m 3 of fluoride, very few of all samples exceeded 1.00 µ/m3 of fluoride, and no non-urban sample contained over 0.16 µg/m3 of fluoride. It was also concluded that only in rare instances would the fluoride concentrations at the sites sampled be in excess of published standards. 相似文献
227.
Rickard Arvidsson Sara Persson Morgan Fröling Magdalena Svanström 《Journal of Cleaner Production》2011,19(2-3):129-137
A life cycle assessment of hydrotreated vegetable oil (HVO) biofuel was performed. The study was commissioned by Volvo Technology Corporation and Volvo Penta Corporation as part of an effort to gain a better understanding of the environmental impact of potential future biobased liquid fuels for cars and trucks. The life cycle includes production of vegetable oil from rape, oil palm or Jatropha, transport of the oil to the production site, production of the HVO from the oil, and combustion of the HVO. The functional unit of the study is 1 kWh energy out from the engine of a heavy-duty truck and the environmental impact categories that are considered are global warming potential (GWP), acidification potential (AP), eutrophication potential (EP) and embedded fossil production energy. System expansion was used to take into account byproducts from activities in the systems; this choice was made partly to make this study comparable to results reported by other studies. The results show that HVO produced from palm oil combined with energy production from biogas produced from the palm oil mill effluent has the lowest environmental impact of the feedstocks investigated in this report. HVO has a significantly lower life cycle GWP than conventional diesel oil for all feedstocks investigated, and a GWP that is comparable to results for e.g. rape methyl ester reported in the literature. The results show that emissions from soil caused by microbial activities and leakage are the largest contributors to most environmental impact categories, which is supported also by other studies. Nitrous oxide emissions from soil account for more than half of the GWP of HVO. Nitrogen oxides and ammonia emissions from soil cause almost all of the life cycle EP of HVO and contribute significantly to the AP as well. The embedded fossil production energy was shown to be similar to results for e.g. rape methyl ester from other studies. A sensitivity analysis shows that variations in crop yield and in nitrous oxide emissions from microbial activities in soil can cause significant changes to the results. 相似文献
228.
Behavioral Ecology and Sociobiology - Shared behavioural traits result from the interaction of two or more individuals, making it difficult to discern which individual is in control of the... 相似文献
229.
Blayne Morgan Rachel Hansgen Wendy Hawthorne 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1127-1140
An odor of unknown origin described as a “tar” or “asphalt” smell has become unbearable for many of Globeville, CO, residents over the past few years. Residents report during odor events burning eyes and throat, headaches, skin irritation, and problems sleeping. This study was undertaken to identify the potential sources of the odor and the concentrations of air pollutants making up the odor by conducting meteorological correlations and sampling for a panel of volatile organic compounds (VOCs), sulfur gases, and polycyclic aromatic hydrocarbons (PAHs) in the neighborhood and near suspected sources. Wind speed and direction data collected every 1 min in the neighborhood indicate that when the odor is noticed, the community is directly downwind of a wood preservation facility and an asphalt roofing facility. Air samples collected during high-intensity odor events have shown concentrations of methylene chloride, hexane, toluene, naphthalene, dibenz[a,h]anthracene, benzo[g,h,i]perylene, and indeno[1,2,3-cd]pyrene, each at least two times higher than background concentrations. Naphthalene and the other PAHs are known pollutants emitted from wood treatment processes, and are known to have a coal tar odor. Naphthalene was present in a sample collected directly adjacent to the Koppers facility and was not present in any background samples. Single-compound odor and health thresholds, however, were never surpassed. Given the technical and regulatory challenges of sampling odors and controlling emissions, it is recommended that Globeville residents and neighboring industry pursue a “good neighbor policy” to solve the odor issue. Specific offending industrial processes could be identified for which there exist cost-effective control technologies that would reduce exposure to odors and air toxics in Globeville.Implications: Meteorological correlations and samples of volatile organic compounds (VOCs), sulfur gases, and polycyclic aromatic hydrocarbons (PAHs) in the Globeville, CO, neighborhood and near suspected sources during odor events indicate potential industrial sources of a transient and noxious odor. Legislative approaches have proven unfruitful and no health or odor thresholds were typically violated. New approaches are warranted to address odor mixture effects in neighborhoods near industrial facilities. 相似文献
230.
Yan Xiaohui Rennie Colin D. Mohammadian Abdolmajid 《Environmental Fluid Mechanics》2020,20(6):1491-1510
Environmental Fluid Mechanics - The influence of channel side slope on flow in strongly curved channel bends is studied numerically. The performances of five different turbulence models are... 相似文献