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431.
Environmental Science and Pollution Research - In this work, Ag-doped ZnO nanoparticles (NPs) were synthesized by a simple green method using a toxic agent-free route for photocatalytic purposes,...  相似文献   
432.
Marine fisheries in coastal ecosystems in many areas of the world have historically removed large-bodied individuals, potentially impairing ecosystem functioning and the long-term sustainability of fish populations. Reporting on size-based indicators that link to food-web structure can contribute to ecosystem-based management, but the application of these indicators over large (cross-ecosystem) geographical scales has been limited to either fisheries-dependent catch data or diver-based methods restricted to shallow waters (<20 m) that can misrepresent the abundance of large-bodied fished species. We obtained data on the body-size structure of 82 recreationally or commercially targeted marine demersal teleosts from 2904 deployments of baited remote underwater stereo-video (stereo-BRUV). Sampling was at up to 50 m depth and covered approximately 10,000 km of the continental shelf of Australia. Seascape relief, water depth, and human gravity (i.e., a proxy of human impacts) were the strongest predictors of the probability of occurrence of large fishes and the abundance of fishes above the minimum legal size of capture. No-take marine reserves had a positive effect on the abundance of fishes above legal size, although the effect varied across species groups. In contrast, sublegal fishes were best predicted by gradients in sea surface temperature (mean and variance). In areas of low human impact, large fishes were about three times more likely to be encountered and fishes of legal size were approximately five times more abundant. For conspicuous species groups with contrasting habitat, environmental, and biogeographic affinities, abundance of legal-size fishes typically declined as human impact increased. Our large-scale quantitative analyses highlight the combined importance of seascape complexity, regions with low human footprint, and no-take marine reserves in protecting large-bodied fishes across a broad range of species and ecosystem configurations.  相似文献   
433.
Connectivity is a fundamental but highly dynamic property of watersheds. Variability in the types and degrees of aquatic ecosystem connectivity presents challenges for researchers and managers seeking to accurately quantify its effects on critical hydrologic, biogeochemical, and biological processes. However, protecting natural gradients of connectivity is key to protecting the range of ecosystem services that aquatic ecosystems provide. In this featured collection, we review the available evidence on connections and functions by which streams and wetlands affect the integrity of downstream waters such as large rivers, lakes, reservoirs, and estuaries. The reviews in this collection focus on the types of waters whose protections under the U.S. Clean Water Act have been called into question by U.S. Supreme Court cases. We synthesize 40+ years of research on longitudinal, lateral, and vertical fluxes of energy, material, and biota between aquatic ecosystems included within the Act's frame of reference. Many questions about the roles of streams and wetlands in sustaining downstream water integrity can be answered from currently available literature, and emerging research is rapidly closing data gaps with exciting new insights into aquatic connectivity and function at local, watershed, and regional scales. Synthesis of foundational and emerging research is needed to support science‐based efforts to provide safe, reliable sources of fresh water for present and future generations.  相似文献   
434.
Public engagement in local environmental planning and decision-making is often advocated on various grounds, both instrumental and normative. Yet in developed countries in the context of renewable energy infrastructure deployment, place attachment, place identity and place-protective action continue to be implicated in public objection. We set out an interdisciplinary change readiness hypothesis of specifically how local participatory scenario or visioning processes that include climate mitigation measures may support the mobilisation of place attachment for climate mitigation, including renewable energy deployment. We hypothesise that local visioning may support movement towards change readiness by helping to anchor unfamiliar social representations of low carbon energy infrastructure and new patterns of urban form in existing, more positive representations of localities and associated attachments. To this end, seeking ways to modify threat perceptions relating to climate change and renewable energy infrastructure is advocated as a key direction for study.  相似文献   
435.
Fungicides are moderately hydrophobic and have been detected in water and sediment, particularly in agricultural watersheds, but typically are not included in routine water quality monitoring efforts. This is despite their widespread use and frequent application to combat fungal pathogens. Although the efficacy of these compounds on fungal pathogens is well documented, little is known about their effects on nontarget fungi. This pilot study, a field survey in southwestern Idaho from April to December 2010 on four streams with varying pesticide inputs (two agricultural and two reference sites), was conducted to assess nontarget impact of fungicides on gut fungi, or trichomycetes. Tissues of larval black flies (Diptera: Simuliidae), hosts of gut fungi, were analyzed for pesticide accumulation. Fungicides were detected in hosts from streams within agricultural watersheds but were not detected in hosts from reference streams. Gut fungi from agricultural sites exhibited decreased percent infestation, density and sporulation within the gut, and black fly tissues had elevated pesticide concentrations. Differences observed between the sites demonstrate a potential effect on this symbiotic system. Future research is needed to parse out the details of the complex biotic and abiotic relationships; however, these preliminary results indicate that impacts to nontarget organisms could have far‐reaching consequences within aquatic ecosystems.  相似文献   
436.
Traditionally, assessment of human health risk caused by contamination of a water supply focuses on the maximum risk to an individual. Here, we introduce a time‐dependent risk assessment method and adapt and explore the reliability, resilience, and vulnerability (RRV) criteria from the surface‐water literature as possible tools for assessing this risk. Time‐dependent risk assessment, including RRV, is applied to two synthetic examples where water quality at a well varies over time. We calculate time‐dependent health risks for discrete periods of exposure to the contaminated water for a variable population. The RRV criteria provide information about time‐dependent risk: probability of an acceptable risk, probability of system recovery, maximum risk, and average exceedance of a prescribed risk threshold. The results demonstrate that episodic contamination events produce fundamentally different time‐dependent risks than long‐term events: these differences, such as generally lower risks for the episodic contamination, can be captured via plots of the risk and the RRV criteria. Furthermore, the evaluation of time‐dependent health risk and the RRV criteria demonstrates significant sensitivity to the shape of the contaminant breakthrough curve, length of exposure, and variability within the population. Overall, analysis of time‐dependent health risks provides substantial insight into the structure of risk, with RRV providing a reasonable framework for the evaluation of these risks.  相似文献   
437.
As a result of human lifestyles and unsustainable consumption patterns, the environment continues to deteriorate and thus inhibit sustainable development. In order to curb this situation and promote a sustainable economy, one of the solution is to reduce conventional products consumption and shift to green products. Over the past 20 years, marketing managers keenly seek to understand the green market; however, inadequate information on how to promote consumers’ green behavioral intentions is slowing the growth of green markets and becomes a barrier for firms when developing segments and communicating strategies for effective promotion of green products in countries like Malaysia where the trend is fairly new. Therefore, this study attempts to examine the impact of environmental knowledge, cultural values, and environmental advertising and determine the moderating effect of income level, education level, and gender on consumers’ green purchase intentions. A survey was administered, and a total of 405 valid questionnaires were obtained. Structural equation modeling technique was used to evaluate the causal model by using SmartPLS 2.0 software. The finding results suggest that cultural values and environmental advertising are the main influences in building green purchase intentions, while environmental knowledge is not significantly related. The results also indicate that education level and gender have a significant positive moderation effect while income did not. This suggests that green purchase intentions’ motivational factors are greater among highly educated individuals, with females in particular. The discussions and implications of these findings are further elaborated.  相似文献   
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This paper analyses the dynamics of land use via the perspectives, motivations and behaviours of local landowners looking at land-use change (through the landowner’s eyes) in the way that the landowners would prefer to do and not to do in various situations. The dynamics are explored in the context of an oil-palm-based biodiesel development in Thailand where the advent of oil palm (OP) has caused the loss of paddy areas. A sequential mixed-method strategy, including 10 in-depth interviews and 180 responses to a questionnaire survey, indicates that the likelihood of a landowner switching traditional land for OP cultivation is affected by a number of factors including age and education of the head of household, number of household farming labourers, amount and source of income, land size and land right. Moreover, the results indicate that success of switching land to OP cultivation was determined by factors influencing willingness and capacity to change. Willingness-related factors are relevant to outcome expectation and social networks and connections while capacity-related factors are relevant to finance, labour, capital, land rights and transportation.  相似文献   
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