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991.
Improving methods for assessing the spatial and temporal resolution of organic compound concentrations in marine environments is important to the sustainable management of our coastal systems. Here we evaluate the use of ethylene vinyl acetate (EVA) as a candidate polymer for thin-film passive sampling in waters of marine environments. Log KEVA−W partition coefficients correlate well (r2 = 0.87) with Log KOW values for selected pesticides and polychlorinated biphenyls (PCBs) where Log KEVA−W = 1.04 Log KOW + 0.22. EVA is a suitable polymer for passive sampling due to both its high affinity for organic compounds and its ease of coating at sub-micron film thicknesses on various substrates. Twelve-day field deployments were effective in detecting target compounds with good precision making EVA a potential multi-media fugacity meter.  相似文献   
992.
Thirteen soils collected from 11 provinces in eastern China were used to investigate the butachlor adsorption. The results indicated that the total organic carbon (TOC) content, clay content, amorphous Fe2O3 content, silt content, CEC, and pH had a combined effect on the butachlor sorption on soil. Combination of the data obtained from the 13 soils in the present study with other 23 soil samples reported by other researchers in the literature showed that Koc would be a poor predictive parameter for butachlor adsorption on soils with TOC content higher than 4.0% and lower than 0.2%. The soils with the ratio of clay content to TOC content (RCO) values less than 60 adsorbed butachlor mainly by the partition into soil organic matter matrix. The soils with RCO values higher than 60 apparently adsorbed butachlor by the combination of the partition into soil organic matter matrix and adsorption on clay surface.  相似文献   
993.
Since United Nations adopted the global Sustainable Development Goals (SDGs) for the next 15 years (2016–2030), sustainable development will further become a core concept and main principle to guide global and national economic and social development. According to this background, strengthening the integrative research on the theories and methodologies of sustainable development has been a strategically important mission. This article provided an analytic framework for sustainability science, named the object-subject-process (OSP) framework for examining the key issues encountered during the theoretical research and policy analysis. This study emphasized that, on the object dimension, sustainable development means to seek for economic and social development within biophysical limits of the earth and the relationship of environment, society, and economy should be containing and complementary rather than parallel and substitute; on the process dimension, sustainable development should adopt both the responsive and proactive strategies for the whole process management which employing pressure-state-response (PRS) model rather than dealing with one part of them; on the subject dimension, sustainable development research should involve the key stakeholders who are kind of collaborate governance rather than separate each other. From the perspective of sustainability science, green economy was utilized as a case study to explore the issues of object, process and subject and also the significance of green economy was discussed in this study.  相似文献   
994.
Communicating science is a multifaceted and complex process, particularly in sustainability science where researchers directly engage with non-academic stakeholder partners. In this insight, we explore the relationship between science communication behaviour and perceptions of stakeholder scientific expertise in a large-scale sustainability-focused research project in the Northeastern United States. We find that higher levels of perceived scientific expertise are associated with dialogic and participatory models of communication, and lower levels of perceived scientific expertise are associated with dialogic and diffusion models of communication. This work, while small in scope, highlights the utility of attending to perceptions of expertise within stakeholder engagement contexts. Implications, limitations, and opportunities for future research are discussed.  相似文献   
995.
The Shale Network is a group of stakeholders collating, publishing, and conducting research on water quality data collected in the northeastern United States experiencing natural gas extraction from shale using hydraulic fracturing. In developing the Shale Network, we have experienced reluctance to share data from all participating sectors. This paper explores this reluctance, identifying barriers to greater collaboration among multiple stakeholders in natural resource management projects. Findings are derived from participant observation of the Shale Network team, surveys conducted during Shale Network workshops, interviews with water quality stakeholders, and participant observation of water quality monitoring training sessions. The barriers identified include perceptions about data problems and quality, technical capacity, regulatory and legal limitations, competition for resources, and resource allocation decisions. This paper identifies strategies the Shale Network has used to overcome data-sharing barriers to expand a culture of data sharing that supports enhanced nature resource management and citizen engagement.  相似文献   
996.
Climate change risks to the coast and coastal developments have been well-documented. In spite of these warnings, new coastal developments are still proposed and built. Australian research has demonstrated how State-level planning documents fail to incorporate recent sea-level rise projections, with researchers demanding more responsiveness to coastal science from planners, policy-makers and developers. This paper takes an alternative approach to the science, planning and coastal development nexus by developing a relational understanding of the barriers to the uptake of science into coastal development decisions. Drawing on qualitative interview material from two recent and non-routine South Australian cases where sea-level rise (SLR) science was contested, and inspiration from actor-network theory's concepts of obligatory passage points, translation, intermediaries and mediators, this research foregrounds the malleability of scientific knowledge and planning protocols. We find that skilful social actors negotiate and re-frame science and planning; clear scientific recommendations can be subsumed to planning process, while clear planning process creates internecine disputes between nomothetic and idiographic science. An implication of this analysis is that the broad narrative of a lack of scientific uptake into coastal development needs to be sensitized to how science and planning interact in practice to legitimate decisions.  相似文献   
997.
The North Water polynya (~76°N to 79°N and 70°W to 80°W) is known to be an important habitat for several species of marine mammals and sea birds. For millennia, it has provided the basis for subsistence hunting and human presence in the northernmost part of Baffin Bay. The abundance of air-breathing top predators also represents a potential source of nutrient cycling that maintains primary production. In this study, aerial surveys conducted in 2009 and 2010 were used for the first time to map the distribution and estimate the abundance of top predators during spring in the North Water. Belugas (Delphinapterus leucas) were not detected north of 77°20′N but were found along the coast of West Greenland and offshore in the middle of the North Water with an abundance estimated at 2245 (95 % CI 1811–2783). Narwhals (Monodon monoceros) were widely distributed on the eastern side of the North Water with an estimate of abundance of 7726 (3761–15 870). Walruses (Odobenus rosmarus) were found across the North Water over both shallow and deep (>500 m) water with an estimated abundance of 1499 (1077–2087). Bearded (Erignathus barbatus) and ringed seals (Phoca hispida) used the large floes of ice in the southeastern part of the North Water for hauling out. Most polar bears (Ursus maritimus) were detected in the southern part of the polynya. The abundances of bearded and ringed seals were 6016 (3322–10 893) and 9529 (5460–16 632), respectively, and that of polar bears was 60 (12–292). Three sea bird species were distributed along the Greenland coast (eiders, Somateria spp.), in leads and cracks close to the Greenland coast (little auks, Alle alle) or widely in open water (thick-billed guillemots, Uria lomvia).  相似文献   
998.
This special issue of AMBIO presents a new approach to sustainability science that goes beyond interdisciplinary research. Using coupled natural and human systems, or landscapes, as multiple case studies in Europe’s East and West knowledge production and learning toward transdisciplinary research was applied in Sweden, countries in Central and Eastern Europe, and Russia. First, the research group Forest-Landscape-Society summarizes the research program (2005–2012) behind this special issue of AMBIO and its development to participate in transdisciplinary research. Second, stakeholders at multiple levels provide their views on the new approach presented and reported.  相似文献   
999.
Multi-model ensemble simulations using three coupled physical-biogeochemical models were performed to calculate the combined impact of projected future climate change and plausible nutrient load changes on biogeochemical cycles in the Baltic Sea. Climate projections for 1961-2099 were combined with four nutrient load scenarios ranging from a pessimistic business-as-usual to a more optimistic case following the Helsinki Commission's (HELCOM) Baltic Sea Action Plan (BSAP). The model results suggest that in a future climate, water quality, characterized by ecological quality indicators like winter nutrient, summer bottom oxygen, and annual mean phytoplankton concentrations as well as annual mean Secchi depth (water transparency), will be deteriorated compared to present conditions. In case of nutrient load reductions required by the BSAP, water quality is only slightly improved. Based on the analysis of biogeochemical fluxes, we find that in warmer and more anoxic waters, internal feedbacks could be reinforced. Increased phosphorus fluxes out of the sediments, reduced denitrification efficiency and increased nitrogen fixation may partly counteract nutrient load abatement strategies.  相似文献   
1000.
The 24-h average coarse (PM10) and fine (PM2.5) fraction of airborne particulate matter (PM) samples were collected for winter, summer and monsoon seasons during November 2008-April 2009 at an busy roadside in Chennai city, India. Results showed that the 24-h average ambient PM10 and PM2.5 concentrations were significantly higher in winter and monsoon seasons than in summer season. The 24-h average PM10 concentration of weekdays was significantly higher (12-30%) than weekends of winter and monsoon seasons. On weekends, the PM2.5 concentration was found to slightly higher (4-15%) in monsoon and summer seasons. The chemical composition of PM10 and PM2.5 masses showed a high concentration in winter followed by monsoon and summer seasons.The U.S.EPA-PMF (positive matrix factorization) version 3 was applied to identify the source contribution of ambient PM10 and PM2.5 concentrations at the study area. Results indicated that marine aerosol (40.4% in PM10 and 21.5% in PM2.5) and secondary PM (22.9% in PM10 and 42.1% in PM2.5) were found to be the major source contributors at the study site followed by the motor vehicles (16% in PM10 and 6% in PM2.5), biomass burning (0.7% in PM10 and 14% in PM2.5), tire and brake wear (4.1% in PM10 and 5.4% in PM2.5), soil (3.4% in PM10 and 4.3% in PM2.5) and other sources (12.7% in PM10 and 6.8% in PM2.5).  相似文献   
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