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981.
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   
982.
The U.S. Geological Survey is conducting a combined pre/post‐closure assessment at a long‐term wastewater treatment plant (WWTP) site at Fort Gordon near Augusta, Georgia. Here, we assess select endocrine‐active chemicals and benthic macroinvertebrate community structure prior to closure of the WWTP. Substantial downstream transport and limited instream attenuation of endocrine‐disrupting chemicals (EDCs) was observed in Spirit Creek over a 2.2‐km stream segment downstream of the WWTP outfall. A modest decline (less than 20% in all cases) in surface water detections was observed with increasing distance downstream of the WWTP and attributed to partitioning to the sediment. Estrogens detected in surface water in this study included estrone (E1), 17β‐estradiol (E2), and estriol (E3). The 5 ng/l and higher mean estrogen concentrations observed in downstream locations indicated that the potential for endocrine disruption was substantial. Concentrations of alkylphenol ethoxylate (APE) metabolite EDCs also remained statistically elevated above levels observed at the upstream control site. Wastewater‐derived pharmaceutical and APE metabolites were detected in the outflow of Spirit Lake, indicating the potential for EDC transport to aquatic ecosystems downstream of Fort Gordon. The results indicate substantial EDC occurrence, downstream transport, and persistence under continuous supply conditions and provide a baseline for a rare evaluation of ecosystem response to WWTP closure.  相似文献   
983.
Contamination of surface waters by pharmaceuticals is now widespread. There are few data on their environmental behaviour, particularly for those which are cationic at typical surface water pH. As the external surfaces of bacterio-plankton cells are hydrophilic with a net negative charge, it was anticipated that bacterio-plankton in surface-waters would preferentially remove the most extensively-ionised cation at a given pH. To test this hypothesis, the persistence of four, widely-used, cationic pharmaceuticals, chloroquine, quinine, fluphenazine and levamisole, was assessed in batch microcosms, comprising water and bacterio-plankton, to which pharmaceuticals were added and incubated for 21 days. Results show that levamisole concentrations decreased by 19 % in microcosms containing bacterio-plankton, and by 13 % in a parallel microcosm containing tripeptide as a priming agent. In contrast to levamisole, concentrations of quinine, chloroquine and fluphenazine were unchanged over 21 days in microcosms containing bacterio-plankton. At the river-water pH, levamisole is 28 % cationic, while quinine is 91–98 % cationic, chloroquine 99 % cationic and fluphenazine 72–86 % cationic. Thus, the most neutral compound, levamisole, showed greatest removal, contradicting the expected bacterio-plankton preference for ionised molecules. However, levamisole was the most hydrophilic molecule, based on its octanol–water solubility coefficient (K ow). Overall, the pattern of pharmaceutical behaviour within the incubations did not reflect the relative hydrophilicity of the pharmaceuticals predicted by the octanol–water distribution coefficient, D ow, suggesting that improved predictive power, with respect to modelling bioaccumulation, may be needed to develop robust environmental risk assessments for cationic pharmaceuticals.  相似文献   
984.
Concentrations of products of biotransformation of polycyclic aromatic hydrocarbons (PBPAH) were measured in bile of five fishes of nutritional, cultural and ecological relevance from the Athabasca/Slave river system. Samples were collected in Alberta and the Northwest Territories, Canada, during three seasons. As a measure of concentrations of PBPAHs to which fishes are exposed and to gain information on the nature and extent of potential exposures of people or piscivorous wildlife, concentrations of biotransformation products of two- and three-ringed, four-ringed and five-ringed PAHs were measured using synchronous fluorescence spectroscopy. Spatial and seasonal differences were observed with greater concentrations of PBPAHs in samples of bile of fish collected from Fort McKay as well as greater concentrations of PBPAHs in bile of fish collected during summer compared to those collected in other seasons. Overall, PBPAHs were greater in fishes of lower trophic levels and fishes more closely associated with sediments. In particular, goldeye (Hiodon alosoides), consistently contained greater concentrations of all the PBPAHs studied.  相似文献   
985.
986.
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988.
Antipredator behavior studies generally assess prey responses to single predator species although most real systems contain multiple species. In multi-predator environments prey ideally use antipredator responses that are effective against all predator species, although responses may only be effective against one predator and counterproductive for another. Multi-predator systems may also include introduced predators that the prey did not co-evolve with, so the prey may either fail to recognize their threat (level 1 naiveté), use ineffective responses (level 2 naiveté) or succumb to their superior hunting ability (level 3 naiveté). We analyzed microhabitat selection of an Australian marsupial (koomal, Trichosurus vulpecula hypoleucus) when faced with spatiotemporal differences in the activity/density levels of one native (chuditch, Dasyurus geoffroii) and two introduced predators (red fox, Vulpes vulpes; feral cat, Felis catus). From this, we inferred whether koomal recognized introduced predators as a threat, and whether they minimized predation risk by either staying close to trees and/or using open or dense microhabitats. Koomal remained close to escape trees regardless of the predator species present, or activity/density levels, suggesting koomal employ this behavior as a first line of defense. Koomal shifted to dense cover only under high risk scenarios (i.e., with multiple predator species present at high densities). When predation risk was low, koomal used open microhabitats, which likely provided benefits not associated with predator avoidance. Koomal did not exhibit level 1 naiveté, although further studies are required to determine if they exhibit higher levels of naiveté (2–3) against foxes and cats.  相似文献   
989.
Experiments in which organisms are reared in treatments simulating current and future pCO2 concentrations are critical for ocean acidification (OA) research. The majority of OA exposure experiments use average atmospheric pCO2 levels as a baseline treatment. We conducted an ecoregion-scale analysis of global carbon chemistry datasets. For many locales, atmospheric pCO2 levels are not an appropriate characterization of marine carbon chemistry. We argue that atmospheric pCO2 should be disregarded when setting baseline treatment conditions and experimental design should rely on measurements of carbon chemistry in a study subject’s habitat. As carbon chemistry conditions vary with space and time, we suggest using a range of pCO2 values as a control rather than a single value. We illustrate this issue with data on the habitat of Euphausia pacifica, which currently lives in waters with a pCO2 around 900 μatm, a concentration much higher than the current global atmospheric mean.  相似文献   
990.
Compared to other cereals, rice has particular strong As accumulation. Therefore, it is very important to understand As uptake and translocation among different genotypes. A field study in Chenzhou city, Hunan province of China, was employed to evaluate the effect of arsenic-contaminated soil on uptake and distribution in 34 genotypes of rice (including unpolished rice, husk, shoot, and root). The soil As concentrations ranged from 52.49 to 83.86 mg kg?1, with mean As concentration 64.44 mg kg?1. The mean As concentrations in rice plant tissues were different among the 34 rice genotypes. The highest As concentrations were accumulated in rice root (196.27–385.98 mg kg?1 dry weight), while the lowest was in unpolished rice (0.31–0.52 mg kg?1 dry weight). The distribution of As in rice tissue and paddy soil are as follows root ? soil > shoot > husk > unpolished rice. The ranges of concentrations of inorganic As in all of unpolished rice were from 0.26 to 0.52 mg kg?1 dry weight. In particular, the percentage of inorganic As in the total As was more than 67 %, indicating that the inorganic As was the predominant species in unpolished rice. The daily dietary intakes of inorganic As in unpolished rice ranged from 0.10 to 0.21 mg for an adult, and from 0.075 to 0.15 mg for a child. Comparison with tolerable daily intakes established by FAO/WHO, inorganic As in most of unpolished rice samples exceeded the recommended intake values. The 34 genotypes of rice were classified into four clusters using a criteria value of rescaled distance between 5 and 10. Among the 34 genotypes, the genotypes II you 416 (II416) with the lowest enrichment of As and the lowest daily dietary intakes of inorganic As could be selected as the main cultivar in As-contaminated field.  相似文献   
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