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111.
工业废水排放量和治理投资费用的预测 总被引:3,自引:1,他引:2
利用1996—2005年相关统计数据以及专项调查数据,对重点排放行业工业废水的产生、排放特征以及治理费用函数进行分析,建立了分行业的宏观工业废水排放和治理费用预测模型,并预测了2006—2020年工业废水排放趋势、投资需求以及减排重点. 结果表明:到2010年,工业废水和CODCr产生量分别为646×108~658×108和1 575×104~2 031×104 t,二者的排放量将分别介于234×108~301×108和441.1×104~609.2×104 t;“十一五"期间工业废水治理投资和治理费用如不能达到8 000×108元,将面临CODCr减排目标不能完成的风险. 相似文献
112.
This paper discusses a method by which individuals working in government, private business, not-for-profit and educational organizations developed a collaborative statewide program involving the exchange of materials from manufacturers, commercial business and not-for-profit organizations in Ohio. 相似文献
113.
Lisa E. Schwanz 《Behavioral ecology and sociobiology》2008,62(8):1351-1358
Parasitized animals may alter their life histories to minimize the costs of parasitism. Organisms are predicted to decrease
investment in current reproduction when parasitism has the greatest impact on current reproductive ability. In contrast, if
parasitism decreases residual reproductive value, hosts should increase current reproductive investment, referred to as fecundity
compensation or terminal investment. In mammalian hosts, parasitic infection most often leads to reductions in current host
reproduction, perhaps attributable to the emphasis on parasites that are unlikely to impact the host’s residual reproductive
value. In this study, the life history response of a rodent, Peromyscus maniculatus, to infection with a parasite that should strongly impact the residual reproductive value of its host (Schistosomatium douthitti, Trematoda) was examined. Infection decreased survival for hosts exposed to a high dose of parasites and was chronic in survivors,
confirming that infection had strong impacts for the residual reproductive value of the host. As predicted, infected mice
increased their reproductive output, producing litters of greater mass due to heavier offspring. However, this increased output
was observed after a greater delay to begin breeding in infected mice and was not observed in animals that suffered early
mortality. The deer mouse S. douthitti system may provide a rare example of fecundity compensation in mammals. 相似文献
114.
Reducing accident occurrence in petrochemical plants is crucial, thus appropriately allocating management resources to safety investment is a vital issue for corporate management as international competition intensifies. Understanding the priority of safety investment in a rational way helps achieve this objective.In this study, we targeted an acrylonitrile plant. First, Dow Chemical's Fire and Explosion Index (F&EI) identified the reaction process as having the greatest physical risk. We evaluated the severity of accidents in the reaction process using the Process Safety Metrics advocated by the Center for Chemical Process Safety (CCPS); however, this index does not express damages a company actually experience. To solve this problem, we proposed a new metric that adds indirect cost to CCPS metrics. We adopted fault tree analysis (FTA) as a risk assessment method. In identifying top events and basic events, we attempted to improve the completeness of risk identification by considering accidents from the past, actual plant operation and equipment characteristics, natural disasters, and cyber-attacks and terrorist attacks. Consequently, we identified the top events with high priority in handling because of serious accidents as fire/explosion outside the reactor, fire/explosion inside the reactor, and reactor destruction. The new CCPS evaluation index proposed in this study found that fire and explosion outside the reactor has the highest severity. We considered the creation of the fault tree (FT) diagram of the top event, estimating the occurrence probability, and identifying the risk reduction part and capital investment aimed at risk reduction. As an economically feasible selection method for risk reduction investment, using the difference in loss amounts before and after safety investments indicated investment priority. 相似文献
115.
The whole relationship between environmental variables and firm performance: Competitive advantage and firm resources as mediator variables 总被引:1,自引:0,他引:1
María D. Lpez-Gamero Jos F. Molina-Azorín Enrique Claver-Corts 《Journal of environmental management》2009,90(10):3110-3121
The examination of the possible direct link between environmental protection and firm performance in the literature has generally produced mixed results. The present paper contributes to the literature by using the resource-based view as a mediating process in this relationship. The study specifically tests whether or not the resource-based view of the firm mediates the positive relationships of proactive environmental management and improved environmental performance with competitive advantage, which also has consequences for financial performance. We also check the possible link between the adoption of a pioneering approach and good environmental management practices. Our findings support that early investment timing and intensity in environmental issues impact on the adoption of a proactive environmental management, which in turn helps to improve environmental performance. The findings also show that a firm's resources and competitive advantage act as mediator variables for a positive relationship between environmental protection and financial performance. This contribution is original because the present paper develops a comprehensive whole picture of this path process, which has previously only been partially discussed in the literature. In addition, this study clarifies a relevant point in the literature, namely that the effect of environmental protection on firm performance is not direct and can vary depending on the sector considered. Whereas competitive advantage in relation to costs influences financial performance in the IPPC law sector, the relevant influence in the hotel sector comes from competitive advantage through differentiation. 相似文献
116.
This paper analyzes the effect of price uncertainty and irreversible investment on the decision of municipalities to switch from landfill waste disposal to recycling by developing a model to predict recycling adoption behavior and applying it to empirical data. It is shown that uncertainty regarding the price of recycled materials may induce a risk neutral municipality to prefer landfill disposal, even when recycling is less expensive. A model is developed to describe the switching process and estimate its parameters using empirical data from 79 municipalities in Israel. The model is then used to predict municipalities' recycling adoption decisions under various assumptions regarding price uncertainty. The results support the hypothesis that price uncertainty is a major obstacle for recycling. Finally, several options for price stabilization are sketched and it is argued that these policies may be effective in establishing viable recycling markets. 相似文献
117.
Fisher's theory of sex allocation predicts that, in a panmictic population, parental investment will be equally distributed between male and female progeny. Most studies on parental investment in nesting solitary bees and wasps use offspring or provision weight as estimators of parental investment and do not corroborate Fisher's theory. The measurement of parental investment may be confounded by several factors. First, the use of offspring or provision size does not account for seasonal variation in foraging costs associated with aging of nesting females. Second, provision or offspring size do not reflect parental investment associated with nest construction. In this two-year study we measured parental investment in a solitary bee. We calculated sex allocation using both provision weight and foraging time as parental investment estimators. Investment in pollen-nectar provisions decreased, while investment in mud structures (nest construction) increased, as the nesting period progressed. Overall investment in provisions per nest was ∼25 times higher than investment in mud. Pollen-nectar foraging trips became longer as the season progressed, but mud trip duration did not vary. Due to weather differences between years, more offspring per female were produced in the first year, but progeny sex ratio and mean offspring size of both sexes were similar between years. Mortality did not differ between sexes. As predicted by Fisher's theory, production cost ratios did not differ from 1 in either year, irrespective of the currency used to estimate parental investment (provision weight or foraging time). Our results strongly support Fisher's theory. 相似文献
118.
Using Economic and Regulatory Incentives to Restore Endangered Species: Lessons Learned from Three New Programs 总被引:2,自引:0,他引:2
Abstract: We studied three new incentive-based programs for restoring endangered species on private lands in the United States: safe harbor, Environmental Defense's Landowner Conservation Assistance Program, and conservation banking. For each program, we gathered data on the number of participating landowners, the number of species targeted for assistance, and the cumulative acreage of enrolled land. Measured in this way, both safe harbor and the Landowner Conservation Assistance Program have been remarkably successful. Landowners are drawn to three aspects of these programs: (1) the removal of regulatory burdens associated with attracting endangered species to their property; (2) technical guidance on how to restore habitats for endangered species; and (3) cost-share assistance for habitat restoration. Technical guidance appears to be more important than either regulatory relief or financial assistance in securing the cooperation of some landowners. Assessing the success or failure of conservation banking proved more difficult, given the relatively small number of banks created to date and the lack of any centralized database on them. However, nearly half of the 47 endangered-species conservation banks we surveyed have sold credits, indicating some success in either acquiring or restoring essential habitats. 相似文献
119.
Mark R. L. Forbes Robert G. Clark Patrik J. Weatherhead Terry Armstrong 《Behavioral ecology and sociobiology》1994,34(2):79-85
We tested several predictions of nest defense theory by observing variation in flushing distance and probability of nest abandonment within and between six species of waterfowl. In these species, only the females incubate eggs and attend offspring. First, we examined whether flushing distance by females varied in relation to clutch size, stage of incubation, and time of season, after controlling for the number of visits made to nests by observers. Revisits by observers appeared to affect flushing distance by females for reasons unrelated to the relative value of the current clutch. We found that as incubation progressed, females allowed observers to approach more closely before flushing from the nest. In some species, females with larger clutches allowed closer approaches to nests before flushing which was also consistent with nest defense theory. In contrast, time of season (Julian date) did not relate to flushing distance for any species. When species were compared, we found that species with moderate to high yearly mortality and high reproductive output per breeding attempt (e.g., northern shoveler and blue-winged teal) were less likely to abandon nesting attempts and exhibited riskier behavior (remained at nests when approached closely by observers) than species that had lower yearly mortality (e.g., mallard). Our results show that flushing distance and patterns of nest abandonment by female ducks conform to several predictions of nest defense theory.Correspondence to: M.R.L. Forbes 相似文献
120.
We recorded behaviour of kestrels (Falco tinnunculus) in western Finland during the courtship (1988–1992), incubation (1989–1991), early nestling (age of young 1–2 weeks, 1989–1992) and late nestling stages (3–4 weeks, 1989–1991) to examine determinants of their parental effort (PE). In males, PE was estimated as the hunting effort (the proportion of budget time spent in flight-hunting) and in females as the food provisioning rate (number of prey items delivered to the nest per hour). The following predictions derived from the parental investment theory were examined. (1) Parents rearing large clutches and broods should invest more in breeding than do parents rearing small clutches and broods. The hunting effort of parents did not increase with clutch or brood size, but males tending large broods had a higher prey delivery rate than males tending small broods (Figs 1–2). (2) PE of parents should increase in the course of the breeding season. In males, this was true only between the incubation and early nestling phases (Fig. 3). (3) The early pairs should invest more in breeding than late ones. This tended to be true during the early (for males) and late nestling phases (for females) (Fig. 4). (4) There should be a negative correlation between PE of mates within pairs, but no evidence for such adjustment was found (Fig. 5). (5) Females mated with bright-coloured attractive males should show higher PE than females mated with dull-coloured males but our results were inconsistent with this prediction. We conclude that PE decisions of kestrels are mainly based on cost-benefit estimates of residual reproductive value, rather than on current investment indicators, like clutch or brood size. This might be beneficial in environments with highly variable survival prospects of offspring caused by pronounced among-year variation in abundance of the main food (microtine rodents). The results also show that hypotheses explaining variation in PE in the short term are not necessarily valid for long-term PE, e.g. tending clutches or broods, which also reflects the demands of female and young. 相似文献