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51.
Water insecurity, induced or intensified due to climate change, has emerged as a key policy challenge in poor and developing countries such as India. Drawing on social cognitive theory, this paper examines the role of perceived collective efficacy—people's shared beliefs about their group's capabilities to accomplish collective tasks—and trust in government as factors influencing Indians' engagement with government water conservation policies. Using a national survey of Indians (N = 4031), we found that individuals with high levels of perceived collective efficacy and trust in government are more likely to support government water conservation policies. Moreover, for individuals with low trust in government, higher collective efficacy is associated with greater policy support. Perceived collective efficacy is also associated with activist behaviours, while distrust is not. Increasing collective efficacy beliefs, for example through mass media channels and targeted campaigns, could help increase citizens' engagement with climate change adaptation policies.  相似文献   
52.
A range of pesticides are available in Australia for use in agricultural and domestic settings to control pests, including organophosphate and pyrethroid insecticides, herbicides, and insect repellents, such as N,N-diethyl-meta-toluamide (DEET). The aim of this study was to provide a cost-effective preliminary assessment of background exposure to a range of pesticides among a convenience sample of Australian residents. De-identified urine specimens stratified by age and sex were obtained from a community-based pathology laboratory and pooled (n = 24 pools of 100 specimens). Concentrations of urinary pesticide biomarkers were quantified using solid-phase extraction coupled with isotope dilution high-performance liquid chromatography–tandem mass spectrometry. Geometric mean biomarker concentrations ranged from <0.1 to 36.8 ng/mL for organophosphate insecticides, <0.1 to 5.5 ng/mL for pyrethroid insecticides, and <0.1 to 8.51 ng/mL for all other biomarkers with the exception of the DEET metabolite 3-diethylcarbamoyl benzoic acid (4.23 to 850 ng/mL). We observed no association between age and concentration for most biomarkers measured but noted a “U-shaped” trend for five organophosphate metabolites, with the highest concentrations observed in the youngest and oldest age strata, perhaps related to age-specific differences in behavior or physiology. The fact that concentrations of specific and non-specific metabolites of the organophosphate insecticide chlorpyrifos were higher than reported in USA and Canada may relate to differences in registered applications among countries. Additional biomonitoring programs of the general population and focusing on vulnerable populations would improve the exposure assessment and the monitoring of temporal exposure trends as usage patterns of pesticide products in Australia change over time.  相似文献   
53.
Under contract to the U.S. Environmental Protection Agency, Research Triangle Institute has been conducting research to improve the precision, accuracy and limit of detection attainable with the EPA Method 25 nonmethane organic (NMO) analyzer. In Method 25, volatile organic carbon (VOC) samples are collected by drawing gas from an emitting source through a dry ice cooled sample trap and into an evacuated collection tank. The hydrocarbon concentration emitted from the source is determined on a per-carbon basis by catalytically converting the trap and tank sample fractions to CO2 and quantitating the amount of CO2 produced using the NMO analyzer. A reduction catalyst evaluation led to the selection of an NMO analyzer reduction catalyst which operates at a moderate temperature and displays no appreciable effect on peak shape. A gas chromatographlc column system which provides better permanent gas separation and hydrocarbon quantitation was also selected for use in the NMO analyzer.  相似文献   
54.
The spatiotemporal distributions of major phytoplankton taxa were quantified to estimate the relative contribution of different microalgal groups to biomass and bloom dynamics in the eutrophic Neuse River Estuary, North Carolina, USA. Biweekly water samples and ambient physical and chemical data were examined at sites along a salinity gradient from January 1994 through December 1996. Chemosystematic photopigments (chlorophylls and carotenoids) were identified and quantified using high-performance liquid chromatography (HPLC). A recently-developed factor-analysis procedure (CHEMTAX) was used to partition the algal group-specific chlorophyll a (chl a) concentrations based on photopigment concentrations. Results were spatially and temporally integrated to determine the ecosystem-level dynamics of phytoplankton community-constituents. Seasonal patterns of phytoplankton community-composition changes were observed over the 3 yr. Dinoflagellates reached maximum abundance in the late winter to early spring (January to March), followed by a spring diatom bloom (May to July). Cyanobacteria were more prevalent during summer months and made a large contribution to phytoplankton biomass, possibly in response to nutrient-enriched freshwater discharge. Cryptomonad blooms were not associated with a particular season, and varied from year to year. Chlorophyte abundance was low, but occasional blooms occurred during spring and summer. Over the 3 yr period, the total contribution of each algal group, in terms of chl a, was evenly balanced, with each contributing nearly 20% of the total chl a. Cryptomonad, chlorophyte, and cyanobacterial dynamics did not exhibit regular seasonal bloom patterns. High dissolved inorganic-nitrogen loading during the summer months promoted major blooms of cryptomonads, chlorophytes, and cyanobacteria. Received: 12 September 1997 / Accepted: 12 December 1997  相似文献   
55.
The outcomes of species recovery programs have been mixed; high‐profile population recoveries contrast with species‐level extinctions. Each conservation intervention has its own challenges, but to inform more effective management it is imperative to assess whether correlates of wider recovery program success or failure can be identified. To contribute to evidence‐based improvement of future conservation strategies, we conducted a global quantitative analysis of 48 mammalian recovery programs. We reviewed available scientific literature and conducted semistructured interviews with conservation professionals involved in different recovery programs to investigate ecological, management, and political factors associated with population recoveries or declines. Identifying and removing threats was significantly associated with increasing population trend and decreasing conservation dependence, emphasizing that populations are likely to continue to be compromised in the absence of effective threat mitigation and supporting the need for threat monitoring and adaptive management in response to new and potential threats. Lack of habitat and small population size were cited as limiting factors in 56% and 42% of recovery programs, respectively, and both were statistically associated with increased longer term dependence on conservation intervention, demonstrating the importance of increasing population numbers quickly and restoring and protecting habitat. Poor stakeholder coordination and management were also regularly cited by respondents as key weaknesses in recovery programs, indicating the importance of effective leadership and shared goals and management plans. Project outcomes were not influenced by biological or ecological variables such as body mass or habitat, which suggests that these insights into correlates of conservation success and failure are likely to be generalizable across mammals.  相似文献   
56.
The Water Framework Directive is the most significant piece of European water legislation to date. This paper looks at the Directive's stakeholder participation requirements, which are crucial to its successful implementation, and represent one of its most novel and potentially far-reaching elements. The Ribble catchment in northwest England is part of a European pilot river basin network tasked by the European Commission with testing the Directive's common implementation strategy guidance, which is designed to aid member states in meeting its requirements. The Ribble pilot, managed by the Environment Agency, is responsible for testing the stakeholder participation element of this guidance. This paper provides an overview of the early stages of the Ribble pilot'sapproach, and discusses stakeholder participation in the context of the Water Framework Directive more broadly.  相似文献   
57.
This article examines specific systematic planning steps that can be used for designing and controlling Triad projects. Triad work strategies act to limit decision uncertainty, expedite schedules to meet project milestones, and reduce costs associated with cleanup activities. As a result, the Triad approach is rapidly increasing in popularity. Good project planning has always been seen as the cornerstone of successful Triad projects. However, the specific steps in the systematic planning process have not been extensively published. Demands of Triad projects, which attempt to make maximum use of innovative technologies and sequencing of activities in a learn‐ as‐you‐go framework, put new demands on regulators and project managers alike. Specific activities and relationships are identified to assist project managers with dynamic work strategies and real‐time measurements to support improved decision making. These include: assembly of stakeholders, a core technical team, and key decisions; development and refinement of a site model; use of demonstrations of methods applicability; development of dynamic work strategies and project sequencing; real‐time data management assessment and presentation; and unitized procurement of technologies and services. © 2004 Wiley Periodicals, Inc.  相似文献   
58.
Lethal and certain sublethal effects of salt brines on adults and subadults of two species of penaeid shrimps, Penaeus setiferus and P. aztecus, were examined to evaluate the potential impact of ocean disposal of brine from solution mining of salt domes. Brines, prepared from dome salt or synthetic sea salt diluted with Brazos River (Texas, USA) water or deionized water, were mixed with seawater and dalivered from a proportional diluter to shrimp held (usually) at 25°C. For each combination of species, salt, and diluent, 90-individual trials were conducted in the fall and spring. The effects of temperature were evaluated separately. Median lethal time was strongly dose-dependent: Median lethal concentrations at 48 and 96 h were 654±42 (95% confidence interval) and 540±41 mOsm kg-1 above ambient seawater, respectively, well above the worst-case predictions for the brine-disposal area. Salt type, diluent type, season or species did not significantly affect brine lethality. Mortality was higher for both species at 30°C and lower for P. setiferus and higher for P. aztecus below 25°C. Lethal brine doses produced tachycardia after 6 (P. setiferus) or 12 h (P. aztecus) of brine exposure. Opacity of abdominal muscles increased with brine concentration. Lethal brine concentrations evoked hyperactivity after 0.75–1.5 h of exposure, significant failure to orient after 6 h and a reduction in general activity after 12 h. Behavior and osmoregulation suggest higher sensitivities to brines made with dome salt or river water and in shrimp tested during the cool seasons.  相似文献   
59.
Partnerships between organisations in humanitarian crisis situations generally are challenging, but at the apex are those established as part of remote management in a context of extreme insecurity. To date, little systematic research has been conducted on arrangements between local organisations that have access to crisis‐affected populations and international organisations that hold the purse strings. This paper presents the findings of nine months of qualitative research conducted with five Syrian local organisations and their international partners engaging in humanitarian action across the Turkey–Syria border, and presents insights into the components of successful partnerships. It redefines capacity along organisational and operational lines, and unpacks how monitoring and evaluation and donor requirements create tension and, at times, place local organisations at risk. The paper highlights the centrality of trust in successful partnerships, and describes the personalisation of the conflict by local organisations. Based on a historical case study of civil society in northern Iraq, it closes with some suggestions for long‐term sustainability.  相似文献   
60.
Episodic death across species of desert shrubs   总被引:2,自引:0,他引:2  
Extreme events shape population and community trajectories. We report episodic mortality across common species of thousands of long-lived perennials individually tagged and monitored for 20 years in the Colorado Desert of California following severe regional drought. Demographic records from 1984 to 2004 show 15 years of virtual stasis in populations of adult shrubs and cacti, punctuated by a 55-100% die-off of six of the seven most common perennial species. In this episode, adults that experienced reduced growth in a lesser drought during 1984-1989 failed to survive the drought of 2002. The significance of this event is potentially profound because population dynamics of long-lived plants can be far more strongly affected by deaths of adults, which in deserts potentially live for centuries, than by seedling births or deaths. Differential mortality and rates of recovery during and after extreme climatic events quite likely determine the species composition of plant and associated animal communities for at least decades. The die-off recorded in this closely monitored community provides a unique window into the mechanics of this process of species decline and replacement.  相似文献   
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