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191.
The use of molecular tools, principally qPCR, versus traditional culture-based methods for quantifying microbial parameters (e.g., Fecal Indicator Organisms) in bathing waters generates considerable ongoing debate at the science–policy interface. Advances in science have allowed the development and application of molecular biological methods for rapid (~2 h) quantification of microbial pollution in bathing and recreational waters. In contrast, culture-based methods can take between 18 and 96 h for sample processing. Thus, molecular tools offer an opportunity to provide a more meaningful statement of microbial risk to water-users by providing near-real-time information enabling potentially more informed decision-making with regard to water-based activities. However, complementary studies concerning the potential costs and benefits of adopting rapid methods as a regulatory tool are in short supply. We report on findings from an international Working Group that examined the breadth of social impacts, challenges, and research opportunities associated with the application of molecular tools to bathing water regulations.  相似文献   
192.
Determining the relationships between the structures of substrates and inhibitors and their interactions with drug-metabolizing enzymes is of prime importance in predicting the toxic potential of new and legacy xenobiotics. Traditionally, quantitative structure activity relationship (QSAR) studies are performed with many distinct compounds. Based on the chemical properties of the tested compounds, complex relationships can be established so that models can be developed to predict toxicity of novel compounds. In this study, the use of fluorinated analogues as supplemental QSAR compounds was investigated. Substituting fluorine induces changes in electronic and steric properties of the substrate without substantially changing the chemical backbone of the substrate. In vitro assays were performed using purified human cytosolic sulfotransferase hSULT2A1 as a model enzyme. A mono-hydroxylated polychlorinated biphenyl (4-OH PCB 14) and its four possible mono-fluoro analogues were used as test compounds. Remarkable similarities were found between this approach and previously published QSAR studies for hSULT2A1. Both studies implicate the importance of dipole moment and dihedral angle as being important to PCB structure in respect to being substrates for hSULT2A1. We conclude that mono-fluorinated analogues of a target substrate can be a useful tool to study the structure activity relationships for enzyme specificity.  相似文献   
193.
Inorganic emissions from livestock production and subsequent deposition of these ions can be a major source of pollution, causing nitrogen enrichment, eutrophication, acidification of soils and surface waters, and aerosol formation. In the poultry house, ammonia and hydrogen sulfide emissions can also adversely affect the health, performance, and welfare of both animals and human operators. The persistence and long life expectancy of ammonia, odors and toxic pollutants from poultry houses may be due to the ability of suspended particulate matter (SPM) to serve as carriers for odorous compounds such as ammonium ions and other inorganic compounds (e.g., phosphate, sulfate, nitrate, etc.). SPM is generated from the feed, animal manure, and the birds themselves. A large portion of odor associated with exhaust air from poultry houses is SPM that has absorbed odors from within the houses. Understanding the fate and transport processes of ammonia and other inorganic emissions in poultry houses is a necessary first step in utilizing the appropriate abatement strategies. In this study, the examination and characterization of ammonium ions, major components of odors and toxic gases from poultry operations, and other ions in suspended particulate matter in a broiler house were carried out using particle trap impactors. The SPM from the particle trap impactors was extracted and analyzed for its ionic species using ion chromatography (IC). The results showed concentrations of polyatomic ions in suspended particulate matter were found to increase with successive flocks and were highly concentrated in the larger size particulate matter. In addition, the ions concentrations appeared to reach a maximum at the middle of flock age (around the fourth week), tapering off toward the end in a given flock (possibly due to ventilation rates to cool off larger birds). Thus, it can be inferred that aged of bedding materials affects the ionic concentrations in aerosol particulate matter more than the age of the birds.

Implications: In the poultry house, toxic gas emissions can adversely affect the health, performance, and welfare of both animals and human operators. The persistence of these toxic pollutants from poultry houses may be due to the ability of suspended particulate matter (SPM) to serve as carriers for these compounds (inorganic ions). Our study showed that polyatomic ions in suspended particulate matter were found to increase with successive flocks and were highly concentrated in the larger size SPM. Understanding the effect of management practices on poultry air emissions will lead to innovative best management practices to safeguard the health and welfare of the animals as well as those of the poultry operators, along with reducing the impact of potential air pollution on the environment.  相似文献   

194.
Corals and coral-associated species are highly vulnerable to the emerging effects of global climate change. The widespread degradation of coral reefs, which will be accelerated by climate change, jeopardizes the goods and services that tropical nations derive from reef ecosystems. However, climate change impacts to reef social–ecological systems can also be bi-directional. For example, some climate impacts, such as storms and sea level rise, can directly impact societies, with repercussions for how they interact with the environment. This study identifies the multiple impact pathways within coral reef social–ecological systems arising from four key climatic drivers: increased sea surface temperature, severe tropical storms, sea level rise and ocean acidification. We develop a novel framework for investigating climate change impacts in social–ecological systems, which helps to highlight the diverse impacts that must be considered in order to develop a more complete understanding of the impacts of climate change, as well as developing appropriate management actions to mitigate climate change impacts on coral reef and people.  相似文献   
195.
The prospect of unprecedented environmental change, combined with increasing demand on limited resources, demands adaptive responses at multiple levels. In this article, we analyze different attributes of farm-level capacity in central Arizona, USA, in relation to farmers’ responses to recent dynamism in commodity and land markets, and the institutional and social contexts of farmers’ water and production portfolios. Irrigated agriculture is at the heart of the history and identity of the American Southwest, although the future of agriculture is now threatened by the prospect of “mega-droughts,” urbanization and associated inter-sector and inter-state competition over water in an era of climatic change. We use farm-level survey data, supplemented by in-depth interviews, to explore the cross-level dimensions of capacity in the agriculture–urban nexus of central Arizona. The surveyed farmers demonstrate an interest in learning, capacity for adaptive management and risk-taking attitudes consistent with emerging theory of capacity for land use and livelihood transformation. However, many respondents perceive their self-efficacy in the face of future climatic and hydrological change as uncertain. Our study suggests that the components of transformational capacity will necessarily need to go beyond the objective resources and cognitive capacities of individuals to incorporate “linking” capacities: the political and social attributes necessary for collective strategy formation to shape choice and opportunity in the future.  相似文献   
196.
A promising approach for addressing sustainability problems is to recognize the unique conditions of a particular place, such as problem features and solution capabilities, and adopt and adapt solutions developed at other places around the world. Therefore, research and teaching in international networks becomes critical, as it allows for accelerating learning by sharing problem understandings, successful solutions, and important contextual considerations. This article identifies eight distinct types of research and teaching collaborations in international networks that can support such accelerated learning. The four research types are, with increasing intensity of collaboration: (1) solution adoption; (2) solution consultation; (3) joint research on different problems; and (4) joint research on similar problems. The four teaching types are, with increasing intensity of collaboration: (1) adopted course; (2) course with visiting faculty; (3) joint course with traveling faculty; and (4) joint course with traveling students. The typology is illustrated by extending existing research and teaching projects on urban sustainability in the International Network of Programs in Sustainability, with partner universities from Europe, North America, Asia, and Africa. The article concludes with challenges and strategies for extending individual projects into collaborations in international networks.  相似文献   
197.
198.
This study takes an historical approach in order to establish how the form and function of the social-ecological system that represents the Bangladesh south-western coastal zone has changed over recent decades. Time series data for a range of ecosystem services and drivers are analysed to define the range of trends, the presence of change points, slow and fast variables and the significant drivers of change. Since the 1980s, increasing gross domestic product and per capita income mirror rising levels of food and inland fish production. As a result, the size of population below the poverty line has reduced by ~17 %. In contrast, non-food ecosystem services such as water availability, water quality and land stability have deteriorated. Conversion of rice fields to shrimp farms is almost certainly a factor in increasing soil and surface water salinity. Most of the services experienced statistically significant change points between 1975 and 1980, and among the services, water availability, shrimp farming and maintenance of biodiversity appear to have passed tipping points. An environmental Kuznets curve analysis suggests that the point at which growing economic wealth feeds back into effective environmental protection has not yet been reached for water resources. Trends in indicators of ecosystem services and human well-being point to widespread non-stationary dynamics governed by slowly changing variables with an increased likelihood of systemic threshold changes/tipping points in the near future. The results will feed into simulation models and strategies that can define alternative and sustainable paths for land management.  相似文献   
199.
Environmental restoration projects are commonly touted for their ecological positives, but such projects can also provide significant socioeconomic and cultural benefits to local communities. We assessed the social dimensions of a large-scale coral reef restoration project in Maunalua Bay, O‘ahu, where >1.32 million kg of invasive marine macroalgae was removed from 11 hectares (90,000 m2; 23 acres) of impacted coral reef in an urbanized setting. We interviewed 131 community stakeholders and analyzed both quantitative and qualitative data to assess human uses of the environment, assess perceptions of environmental health, and characterize social dimensions (+/?) associated with the invasive algae removal effort. Results indicate substantial direct economic benefits, including the creation of more than 60+ jobs, benefiting more than 250 individuals and 81 households. The project helped develop a skilled workforce in a local business dedicated to environmental restoration and increased the capacity of community organizations to address other threats to reefs and watersheds. Other major benefits include revitalization of Native Hawaiian cultural practices and traditions and the successful use of harvested invasive algae as compost by local farmers. Our results show the project heightened community awareness and a broader sense of stewardship in the area, creating enabling conditions for collective community action. Our findings show that restoration projects that explicitly incorporate efforts to build community awareness, involvement, and a shared responsibility for a site may ultimately create the long-term capacity for sustainable stewardship programs. We conclude by discussing lessons learned for engaging productively with communities in environmental restoration and stewardship, which remains a central focus in conservation worldwide.  相似文献   
200.
Corridors (variably called landscape linkages, connectors, and gateways) are expanses of a landscape that facilitate the flow or movement of individuals, genes, and ecological processes. Protected areas with their buffer zones and the corridors that connect them are cornerstones of modern conservation actions to maintain the biodiversity we have and restore what we have lost. Policy and governance to guide the establishment and management of protected areas and supporting buffer zones is well established in the Central Indian Highlands. A policy and governance structure to create the context and enabling conditions for corridor maintenance, creation, and recovery is emerging but is constrained by the reigning land-management paradigm that separates conservation from development rather than mainstreaming species and habitat conservation into the rural development agenda. Well-nourished, healthy human populations and healthy ecosystems are inextricably linked. The worsening ecological conditions in the Central Indian Highlands can trigger the emergence of a common agenda for an inclusive, caring, and environment-friendly mode of development. The alternative is the business-as-usual scenario: a continuation of worsening ecological conditions. Entry points through the biodiversity, agriculture production, resource extraction, and economic/social sectors to enable integrated sustainable landscape management are identified. These include deepening what it means to successfully conserve a species combined with explicit threat analysis for at-risk tigers and the landscapes that supports them; landscape scenario modeling to advance communication by synthesizing diverse forms of research and articulating and evaluating alternative socio-economic futures; and the use of the smart green infrastructure process as an approach to development rather than only as a way to mitigate environmental damage. Models are presented to scale up from isolated conservation interventions to collective impact that unites supportive government partners with individuals, NGOs, and economic interests to achieve viable long-term relationships in human and natural systems to value, maintain, and recover landscape connectivity.  相似文献   
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