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731.
Policy-makers view community resilience as fundamental to mitigating loss and damage from climate-related disasters. Although energy has been devoted to defining resilience, less effort has been devoted to analysing the effects of resilience on loss and damage, which is critical in places with limited capacity for adaptation. We use survey data to develop a composite index of community resilience in Fiji and then evaluate the extent to which community resilience mitigates loss and damage. We find that community resilience is negatively correlated with damages over which human intervention may be effective, but not with damages over which intervention is less effective, suggesting that community resilience may limit impacts. We further find that this result holds for a cyclone (about which communities had substantial advance warning) but not for river flooding (for which communities had little advanced warning), suggesting that early warning is necessary for community resilience to become responsive.  相似文献   
732.
Membrane bioreactor treatment of commonly used organophosphate pesticides   总被引:1,自引:0,他引:1  
Five pesticide formulations registered for use in Canada containing organophosphate-insecticide active ingredients azinphos-methyl, chlorpyrifos, diazinon, malathion and phorate were subjected to treatment by membrane bioreactor (MBR) technology. The target active ingredients were introduced to the MBR at ppm level concentrations. The biodegradation of these compounds was analyzed daily using selected ion monitoring gas chromatography-mass spectrometry (GC/MS-SIM) following extraction of the analytes using solid-phase extraction (SPE). Amounts measuring 83 % to 98 % of the target analytes were removed with steady-state concentrations being reached within 5 days of their introduction. The dissolved oxygen, temperature, pH, and total heterotrophic bacterial population were monitored daily to ensure optimal conditions for biodegradation. The quality of the effluent from the MBR was assessed daily through spectrophotometric methods. Measurements were conducted for the concentration of ammonia, nitrate, nitrite, total and reactive phosphorus, as well as the chemical oxygen demand (COD) of the effluent. This study demonstrated that the MBR technology is feasible and efficient for treatment of organophosphate pesticides without introducing additional chemical additives.  相似文献   
733.
The perspectives of residents are brought together in this assembly of statements concerning the management of hexachlorobenzene waste in Botany, a southeastern suburb of Sydney. The paper indicates how residents have responded as participants in public participation exercises, and the contribution made by lay experts in the search for a negotiated solution to the problems of legacy wastes. Resident comments on the role of independent scientific experts, on legal liability, and on the State Government sponsored Commission of Inquiry, indicate the deficit of resources faced by the local community. The paper provides insights into the status of citizen knowledge in environmental controversies and the pitfalls of participatory processes.  相似文献   
734.
Intractable industrial legacies present new challenges to governance. Amongst the persistent organic pollutants, now managed internationally under the Stockholm Convention, hexachlorobenzene (HCB) stands out in all three classes of chemicals (pesticides, industrial chemicals and unintended by-products). This paper introduces twelve interdisciplinary papers contributing to our understanding of decision-making processes using a case study of HCB and industry-community relations in Sydney's industrial heartland. In this collection, authors align new political theory and emerging management theory, and they analyse the case study from several disciplines. Disputes such as that over HCB destablilise the political/administrative/technoscientific regime that is the modern state. Citizens engage in 'sub-political' processes which require recognition of what Ulrich Beck and others have termed 'individualisation'. This sees decision-forming and decision-making functions push outwards into community-driven structures. There we find new styles of public participation, resolution of asymmetries between knowledge and expertise, and new corporate behaviour.  相似文献   
735.
The Sacramento-San Joaquin Delta, the landward reach of the San Francisco Estuary, provides habitat for threatened delta smelt, endangered winter-run Chinook salmon, and other species of concern. It is also the location of huge freshwater diversion facilities that entrain large numbers of fish. Reducing the entrainment of listed fishes into these facilities has required curtailment of pumping, reducing the reliability of water deliveries. We reviewed the first 5 years (2001–2005) of the Environmental Water Account (EWA), a program instituted to resolve conflicts between protecting listed fishes and providing a reliable water supply. The EWA provided fishery agencies with control over 0.2–0.4 km3 of water to be used for fish protection at no cost to users of exported water, and fish agencies guaranteed no disruption of water supply for fish protection. The EWA was successful in reducing uncertainty in water supply; however, its contribution to the recovery of listed fishes was unclear. We estimated the effectiveness of the EWA to be modest, increasing the survival of winter-run Chinook salmon by 0–6% (dependent on prescreen mortality), adult delta smelt by 0–1%, and juvenile delta smelt by 2–4%. Allocating EWA water for a single life stage of one species could provide larger gains in survival. An optimally allocated EWA of equal size to the median of the first 5 years could increase abundance of juvenile delta smelt up to 7% in the springs of dry years. If the EWA is to become a long-term program, estimates of efficacy should be refined. If the program is to be held accountable for quantitative increases in fish populations, it will be necessary to integrate scientific, possibly experimental, approaches.  相似文献   
736.
Territoriality is an emerging concept of importance in organizations. Unfortunately, there does not exist currently a valid measure of territoriality with which to conduct research on territoriality in organizations. I developed a theoretically driven four-factor measure of territoriality. Six hundred and sixty-three people working in office settings completed an online survey about their territorial behaviors. Using confirmatory factor analysis I found that the four-factor structure had acceptable fit. I also found preliminary evidence of construct validity. Collectively, the results support the validity of the measure, thus providing an instrument for studying territoriality in organizations. I then discuss specific implications of this measure for both research and practise.  相似文献   
737.
Changes in pesticide adsorption with time at high soil to solution ratios   总被引:2,自引:0,他引:2  
Kah M  Brown CD 《Chemosphere》2007,68(7):1335-1343
Adsorption of six pesticides (2,4-D, dicamba, fluroxypyr, fluazifop-P, metsulfuron-methyl and flupyrsulfuron-methyl) in nine contrasting soils was measured using two techniques: (i) a classical batch method and (ii) a centrifugation method that allowed the measurement of adsorption at a realistic soil to solution ratio after one and seven days. Although the batch method gived significantly higher values of Kd than the centrifugation method for the more strongly sorbed molecules in the more sorptive soils, it tended to give lower adsorption coefficients compared to the centrifugation method when adsorption was lower. Discrepancies between the two methods were probably mainly due to the vigorous shaking applied in the batch technique that artificially enhances the availability of adsorption sites. This implies that shortly after application, more pesticide may be present in the soil solution and thus be available for degradation, plant uptake or leaching than will be predicted from adsorption coefficient determined using the batch method. Adsorption significantly increased between one and seven days and the extractability of total residues decreased with time. The increase in adsorption was not directly related to the level of adsorption although it was more important in soils containing more organic carbon (p=0.022). These results confirm the importance of time-dependent processes and the necessity to include them in risk assessment procedures. The centrifugation technique is a useful method to measure adsorption of pesticides at realistic soil moisture contents and seems to be an adequate technique to characterise the fraction of pesticide that is available for leaching at a given time after application.  相似文献   
738.
Vacuum filter socks were evaluated for recovery efficiency of powdered Bacillus atrophaeus spores from two non-porous surfaces, stainless steel and painted wallboard and two porous surfaces, carpet and bare concrete. Two surface coupons were positioned side-by-side and seeded with aerosolized Bacillus atrophaeus spores. One of the surfaces, a stainless steel reference coupon, was sized to fit into a sample vial for direct spore removal, while the other surface, a sample surface coupon, was sized for a vacuum collection application. Deposited spore material was directly removed from the reference coupon surface and cultured for enumeration of colony forming units (CFU), while deposited spore material was collected from the sample coupon using the vacuum filter sock method, extracted by sonication and cultured for enumeration. Recovery efficiency, which is a measure of overall transfer effectiveness from the surface to culture, was calculated as the number of CFU enumerated from the filter sock sample per unit area relative to the number of CFU enumerated from the co-located reference coupon per unit area. The observed mean filter sock recovery efficiency from stainless steel was 0.29 (SD = 0.14, n = 36), from painted wallboard was 0.25 (SD = 0.15, n = 36), from carpet was 0.28 (SD = 0.13, n = 40) and from bare concrete was 0.19 (SD = 0.14, n = 44). Vacuum filter sock recovery quantitative limits of detection were estimated at 105 CFU m(-2) from stainless steel and carpet, 120 CFU m(-2) from painted wallboard and 160 CFU m(-2) from bare concrete. The method recovery efficiency and limits of detection established in this work provide useful guidance for the planning of incident response environmental sampling for biological agents such as Bacillus anthracis.  相似文献   
739.
Biosolids and woody debris were applied with target C:N ratios of 8:1 to 50:1 to phytotoxic, acidic, high metal mine tailings to test the effect of amendment C:N ratio on native plant restoration. Total soil C decreased over time indicating an active microbial community. The 8:1 treatment initially had no growth, the highest plant cover for the final sampling (86.8+/-13.8%) and the lowest number of species (3.33+/-0.4). The greatest number of species was in the 30:1 treatment (5.44+/-0.45). Plant cover increased over time for all treatments from 44.7% in 2001 to 71% in 2005. This response was consistent across all except for the 30:1 treatment, which showed a slight decrease in the final year (65+/-11%). Volunteer species and evidence of animal grazing were observed in all amended plots. Results indicate that a C:N ratio>/=20:1 increased species diversity.  相似文献   
740.
Environmental Modeling & Assessment - In Europe, the two main nuclear accident response decision support systems in use are ARGOS and JRODOS, both of which make use of the FDMT (Food Chain and...  相似文献   
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