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121.
-- An environmental assessment of the transformation and transport pathways of hexachlorocyclopentadiene (hex) in simulated aquatic ecosystems is presented. Hydrolytic and photolytic disappearance rate constants in distilled and natural waters and in sediment-water systems are given. Sediments in defined sediment-water systems do not significantly affect the disappearance rate constants, compared to distilled water values, for the hydrolytic and photolytic processes. Water solubility, octanol/water partition coefficient, and vapor pressure for hex are also reported and compared with literature values. Fate and transport assessment using an evaluative model indicates that hex will not likely reach substantial steady-state concentrations in the various compartments of the simulated ecosystems. The results also indicate that photolysis and, to a lesser extent, hydrolysis are the predominant degradation processes; export via the water column is the predominant transport process.  相似文献   
122.
In a region that is highly sensitive to tectonic instability, the fragile nature of the Himalayas becomes further adversely affected by anthropogenic intervention. In the present study observations indicate that the landsliding process occurs along various tectonic zones where it is assisted by human activities. Bedding and joint plane dip slopes, high joint and joint set frequencies, low vegetation cover, high monsoonal rainfall, thin soil cover and anthropogenic activities were found to be the main causative factors of the landslides. Anthropogenic activities include local path, canal and road construction, mining and quarrying, overgrazing, deforestation and unscientific agricultural practices, such as tilling steeper slopes (>30) without contour benches and without provision of drainage ditches, and overcropping without giving rest to the overtaxed soils. Where slope conditions are critical human activities should be controlled so as to minimise the slope failure processes. Various recommendations are proposed.  相似文献   
123.
Beneficial and environmentally safe recycling of flue gas desulfurization (FGD) products requires detailed knowledge of their chemical and physical properties. We analyzed 59 dry FGD samples collected from 13 locations representing four major FGD scrubbing technologies. The chemistry of all samples was dominated by Ca, S, Al, Fe, and Si and strong preferential partitioning into the acid insoluble residue (i.e., coal ash residue) was observed for Al, Ba, Be, Cr, Fe, Li, K, Pb, Si, and V. Sulfur, Ca, and Mg occurred primarily in water- or acid-soluble forms associated with the sorbents or scrubber reaction products. Deionized water leachates (American Society for Testing and Materials [ASTM] method) and dilute acetic acid leachates (toxicity characteristic leaching procedure [TCLP] method) had mean pH values of >11.2 and high mean concentrations of S primarily as SO(2-)4 and Ca. Concentrations of Ag, As, Ba, Cd, Cr, Hg, Pb, and Se (except for ASTM Se in two samples) were below drinking water standards in both ASTM and TCLP leachates. Total toxicity equivalents (TEQ) of dioxins, for two FGD products used for mine reclamation, were 0.48 and 0.53 ng kg(-1). This was similar to the background level of the mine spoil (0.57 ng kg(-1)). The FGD materials were mostly uniform in particle size. Specific surface area (m2 g(-1)) was related to particle size and varied from 1.3 for bed ash to 9.5 for spray dryer material. Many of the chemical and physical properties of these FGD samples were associated with the quality of the coal rather than the combustion and SO2 scrubbing processes used.  相似文献   
124.
This study examines the relationship between violation of an employee's psychological contract and civic virtue behavior. A psychological contract is a set of beliefs regarding mutual obligations between employee and employer. One hundred twenty-six MBA alumni were surveyed at the time of hire (T1), and after 18 months (T2) and 30 months (T3) on the job. When employees felt that their employers had failed to fulfil employment obligations at T2, they were less likely to engage in civic virtue behavior at T3. There was evidence that this relationship was partly mediated by trust. These findings have implications for research on OCB and for managers seeking to maintain employee citizenship behavior.  相似文献   
125.
This paper presents a ranked set sample allocation procedure that is optimal for a number of nonparametric test procedures. We define a function that measures the amount of information provided by each observation given the actual joint ranking of all the units in a set. The optimal ranked set sample allocates order statistics by maximizing this information function. This paper shows that the optimal allocation of order statistics in a ranked set sample is determined by the location of the mode(s) of the underlying distribution. For unimodal, symmetric distributions, optimal allocation always quantifies the middle observation(s). If the underlying distribution with cdf F is a multi-modal distribution with modes , then the optimal allocation procedure quantifies observations at in a set of size m. We provide similar results for unimodal, asymmetric distributions. We also propose a new sign test which considers the relative positions of the quantified observations from the same cycle in a ranked set sample. The proposed sign test provides improvement in the Pitman efficiency over the ranked set sample sign test of Hettmansperger (1995). It is shown that the information optimal allocation procedure induced by Pitman efficiency is equivalent to the optimal allocation procedure induced by the information criteria. We show that the finite sample distribution of the proposed test based on this optimal design is binomial.  相似文献   
126.
Adaptation to climate change in Europe has only recently become a true policy concern with the management of extreme events one priority item. Irrespective of future climatic changes increasing the need for systematic evaluation and management of extremes, weather-related disasters already today pose substantial burdens for households, businesses and governments. Research in the ADAM project identified substantial direct risks in terms of potential crop and asset losses due to combined drought and heatwave, as well as flood hazards in Southern and Eastern Europe, respectively. This paper focuses on the indirect, medium to longer term economic risks triggered by the direct risks and mediated by policy responses. We present a selection of three economic impact and adaptation assessments and modelling studies undertaken on extreme event adaptation in Europe. Responding to a need for more economically based adaptation assessments, we address some relatively unresearched issues such as the understanding of past adaptation, the role of market response to impacts as well as government’s ability to plan for and share out extreme event risks. The first analysis undertakes an empirical exploration of observed impacts and adaptation in the agricultural sector in the UK comparing the impact of consecutive extreme events over time in order to determine whether adaptation has occurred in the past and whether this can be used to inform future estimates of adaptation rates. We find that farmers and the agricultural sector clearly have adapted to extreme events over time, but whether this rate can be maintained into the future is unclear, as some autonomous adaptation enacted seemed rather easy to be taken. Markets may mediate or amplify impacts and in the second analysis, we use an economic general equilibrium model to assess the economic effects of a reduction in agricultural production due to drought and heatwave risk in exposed regions in Spain. The analysis suggests that modelled losses to the local economy are more serious in a large-scale scenario when neighbouring provinces are also affected by drought and heatwave events. This is due to the supply-side induced price increase leading to some passing on of disaster costs to consumers. The simulation highlights the importance of paying particular attention to the spatial and distributional effects weather extremes and possibly changes therein induced by climate change may incur. Finally, we discuss how national governments may better plan their disaster liabilities resulting from a need to manage relief and reconstruction activities post event. We do so using a risk based economic planning model assessing the fiscal consequences associated with the coping with natural extremes. We identify large weather-related disaster contingent liabilities, particularly in the key flood hot spot countries Austria, Romania, and Hungary. Such substantial disaster liabilities (“hidden disaster deficits”) when interacting with weak fiscal conditions may lead to substantial additional stress on government budgets and reduced fiscal space for funding other relevant public investment projects. Overall, our paper suggests the importance of respecting the specific spatial and temporal characteristics of extreme event risk when generating information on adaptation decisions. As our adaptation decisions considered, such as using sovereign risk financing instruments are associated with a rather short time horizon, the analysis largely focuses on the management of today’s extreme events and does not discuss in detail projections of risks into a future with climate change. Such projections raise important issues of uncertainty, which in some instances may actually render future projections non-robust, a constraint to be kept in mind when addressing longer term decisions, which at the same time should account for both climate and also socioeconomic change.  相似文献   
127.
128.
There are gaps in the existing climate change adaptation literature concerning the design of spatial planning instruments and the relationship between policy instruments and the sociopolitical barriers to adaptation reform. To help address this gap, this article presents a typology of spatial planning instruments for adaptation and analyses the pattern of instrument choice in Australian planning processes in order to shed light on contextual factors that can impede adaptation. The analysis highlights how policy design can amplify the barriers to adaptation by arranging policy actors in ways inimical to reform and stripping decision makers of the instruments necessary to make and sustain desired policy changes.  相似文献   
129.
Quick, simple and efficient multi-residue analytical methods were developed and validated for the determination of organophosphorous insecticides from polished and cooked rice. Polished rice was extracted using a simple, automated technique namely accelerated solvent extraction (ASE) using dichloromethane as the extraction solvent. Cooked rice was extracted with acetone and cleaned up using dispersive-solid phase extraction (D-SPE) technique. The single step extraction method adopted for polished rice using accelerated solvent extractor provided satisfactory recovery for eight organophosphorus pesticides (OPPs) which ranged from 85.5–116.7%; 90.0–110.3% and 93.5–118.8% at 1, 5 and 10 limit of quantification (LOQ) levels, respectively. The recovery of cooked rice was in the range of 74–124%; from 75–100% and from 73–87% for 1, 5 and 10 level of fortification, respectively. The total uncertainty was evaluated, taking four main independent sources viz., weighing, purity of the standard, GC calibration curve and repeatability under consideration. The expanded uncertainty was found to be in the range of 5–20%.  相似文献   
130.
There is global interest in recovering locally extirpated carnivore species. Successful efforts to recover Louisiana black bear in Louisiana have prompted interest in recovery throughout the species’ historical range. We evaluated support for three potential black bear recovery strategies prior to public release of a black bear conservation and management plan for eastern Texas, United States. Data were collected from 1,006 residents living in proximity to potential recovery locations, particularly Big Thicket National Preserve. In addition to traditional logistic regression analysis, we used conditional probability analysis to statistically and visually evaluate probabilities of public support for potential black bear recovery strategies based on socioeconomic characteristics. Allowing black bears to repopulate the region on their own (i.e., without active reintroduction) was the recovery strategy with the greatest probability of acceptance. Recovery strategy acceptance was influenced by many socioeconomic factors. Older and long-time local residents were most likely to want to exclude black bears from the area. Concern about the problems that black bears may cause was the only variable significantly related to support or non-support across all strategies. Lack of personal knowledge about black bears was the most frequent reason for uncertainty about preferred strategy. In order to reduce local uncertainty about possible recovery strategies, we suggest that wildlife managers focus outreach efforts on providing local residents with general information about black bears, as well as information pertinent to minimizing the potential for human–black bear conflict.  相似文献   
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