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1.
2.
A model of the implementation process as applied in pollution control is developed. It differs from previous bureaucracy models in that it subjects the control agency to pressures from both firms and procontrol citizen groups. Each of these three actors maximizes utility over environmental quality and some other variable. Environmental quality may be in the actor's preference function or it may represent derived demand. Working through the agency budget and other policy variables, each actor constrains another actor's attempts to move policy in preferred directions. This results in movement toward a concensus environmental quality, not necessarily the efficient quality. Several institutional changes are analyzed to demonstrate the workings of the model.  相似文献   

3.
Hierarchical control formulations are given for a simple predator-prey model: self-optimization of one subsystem, natural multi-goal optimization, man's multiparameter control of an ecosystem and man's control of a self-optimizing ecosystem. Natural multigoal optimization suggests how several levels of an ecosystem can be optimized simultaneously. The idea of management of a self-optimizing ecosystem takes into account the reactions of the ecosystem to man's activity.  相似文献   

4.
The goal of this paper is to determine the likely effect on a firm's control actions of alternative implementation and enforcement policies available to the control agency. Three alternatives are studied, legal enforcement through the new source performance standards set forth by EPA, and two effluent fee enforcement alternatives. First, a generalized model of the effects of implementation and enforcement policies on the firm's control action is developed. This model assumes that the firm is an expected cost minimizer. The model is then applied to the case of particulate matter discharges from coal-fired power plants in order to estimate empirically the effect of policy alternatives on the firm's control efforts. Finally, the results of the model and its empirical application are used to develop policy functions which relate control to the values of various policy parameters. These results lead us to several policy recommendations.  相似文献   

5.
This article derives Pigouvian-type corrective measures for reciprocal externalities when non-Nash behavior characterizes the participants. These reciprocal externalities may involve various kinds of environmental pollutants, such as acid rain. A comparison between corrective measures for Nash and non-Nash behavior demonstrates that positive conjectures, regarding the other agent's externality-generating activity, have an expectation-internalizing influence that usually reduces the required corrective measures. Negative conjectures (e.g., free-riding expectations), however, have an expectation-externalizing effect that increases the required corrective measures. The article analyzes both two-person and n-person externalities.  相似文献   

6.
The household production function is an intuitively appealing way to model man's interaction with nature. This paper models the interaction between the household's behavior and publicly provided inputs into wildlife recreation. The paper shows how to compute benefits, assuming that the household production function is known. The household production function approach collapses to the simple travel cost approach when households are unable to substitute their own inputs for publicly provided inputs. In addition, the paper demonstrates the conditions under which the parameters of cost and preference functions can be identified. The conditions for identification are quite restrictive when several choices are endogenous.  相似文献   

7.
Two species of marine bivalve, Cerastoderma edule (Linnaeus) and Macoma balthica (Linnaeus), were exposed to particles contaminated with three commercial polychlorinated biphenyl (PCB) mixtures, Aroclors® 1242, 1254 and 1260. The accumulation of PCB in bivalve tissue was monitored for periods of up to 40 days. In addition to measuring total PCB concentrations, which reached 60 ppm of Aroclor 1242 in M. balthica, the fate of individual PCB homologues of different chlorine content, ranging from 2 to 8 chlorine atoms per biphenyl molecule, was also determined. Selective accumulation of PCBs with 5 chlorine atoms per biphenyl molecule occurred, whilst isomers of very low and very high molecular weights were accumulated at much slower rates.  相似文献   

8.
A local referendum on a proposed pulp mill in eight New Hampshire towns provides a particularly apt sample for examining preferences on environmental issues. Interviews with 359 voters are examined to test various determinants of voting behavior. A utility maximizing model is tested using multiple-regression logit techniques. Significant variables are respondent's location, income, occupation, and education and the initial environment of the community. There is a brief discussion of public policy issues which these results may illuminate.  相似文献   

9.
Summary The theory that female mammals in poor condition may increase individual fitness by skewing the sex ratio of their offspring toward daughters and by investing more resources in daughters than in sons was tested in hamsters. Newly mated experimental females were food-restricted during pregnancy and lactation (RR) or during lactation only (AR). Controls received food ad libitum. Maternal body weights were assessed daily from mating to 25 days postpartum. Litter survival (% litters with at least one pup surviving on any day), litter size, offspring sex ratios (=% males), and pup weights were monitored daily from birth (Day 1) to Day 25. All control and AR dams gave birth 16 days after mating. Gestation was extended by 1–3 days for 35.4% of RR dams. RR dams weighed significantly less at parturition than controls and AR females. During lactation, AR females showed the greatest weight loss and control females the least. AR weight loss exceeded that of RR females, possibly because the former maintained larger litters. Survival was highest for controls, intermediate for AR, and lowest for RR litters. Mean sex ratio at birth was significantly less for RR (40.7%) than for control (49.6%) and AR (48.8%) litters. RR sex ratio did not change significantly postnatally. Sex ratios of control and AR litters never differed statistically from 50%. Control male pups were significantly heavier than their sisters throughout the experiment. No significant gender differences were observed for AR pup weights after Day 2 postpartum. RR female offspring weighed more than their brothers throughout the experiment, and this difference was statistically significant immediately prior to the time that pups began to feed independently (Days 14–17). RR female pup weights were similar to, and sometimes significantly greater than, weights of control daughters during the period of postnatal maternal investment. Control males were always heavier than males from the other treatments. Patterns of weight gain by AR and RR males varied with age. We conclude that underfed female hamsters are able to adjust the sex ratio of offspring prenatally and parental investment postnatally to favor daughters.  相似文献   

10.
Polychlorinated biphenyl (PCB) congeners were analyzed by high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) of whole blood samples taken from 24 healthy adult Japanese volunteers (12 males and 12 females; age range 25–46 years). On average, 95 PCB congeners were detected in whole blood samples. The mean of total PCB concentration in whole blood was 771.9 pg g–1 whole blood (139.6 ng per g-lipid). Congener-specific analysis identified the predominant PCB congeners as #153 (22.2), #180 (11.6), #138 (8.4), #182/187 (6.6), #118 (5.6), #163/164 (5.0), #99 (3.9), #74 (3.6), #146 (3.3), #170 (3.0) and #156 (2.2), representing 75.6 of all PCBs detected in the human blood samples. Among the predominant PCB congeners, #153, #180, #138, #187 #118, #99 and #74 had chlorine as the substituent at the 2-, 4- and 5- positions of the phenyl-ring. In human blood in Japanese individuals, it is assumed that these congeners would be characteristic of the entire population, based on the relation between PCB ingestion and metabolism. Measuring 209 PCB congeners has the advantage of providing detailed information regarding the congener distribution within the blood samples, which can be compared to congener patterns in other matrices. Congener-specific analysis of 209 PCB congeners is especially useful in evaluating human exposure to PCBs.  相似文献   

11.
The exploitation of a nonrenewable natural resource, such as petroleum or mineral ores, is analyzed in a stochastic framework with price uncertainty. The market setting may be either monopolistic or competitive. We demonstrate that the rate of extraction varies directly with the resource owner's willingness to accept risk. Rish-preferring owners use the resource more rapidly than risk-neutral owners, who in turn deplete the resource more rapidly than risk-averse owners. It is also seen that the usual practice of increasing the discount rate to account for risk induces a more rapid rate of resource use, when in fact a slower rate of depletion is desired.  相似文献   

12.
A widely recognized article by Smith suggests that harvesting leading to species extinction may be socially optimal, provided that the species growth-potential is sufficiently low. It is shown that this conclusion hinges on special assumptions about harvest technology which, despite a superficial compatibility with neoclassical production theory, contradict a basic postulate of a pioneering article by Gordon. As soon as Gordon's postulate is taken into account, while all other aspects of Smith's model are maintained, it turns out that even a species with a very low growth potential should not become extinct.  相似文献   

13.
Abstract: One of the primary approaches to environmental conservation emphasizes economic development. This conservation‐and‐development approach often ignores how development affects sociocultural characteristics that may motivate environmental behaviors (actions that actively benefit or limit one's negative impacts on the environment). Evolutionary anthropologists espouse a theoretical perspective that supports the conservation‐and‐development approach. Others believe sociocultural factors are the foundation of environmental behavior and worry that development will erode the values and norms that may shape such behavior. My research assistants and I surveyed 170 individuals from eight villages in two communities in Bhutan to explore whether economic (wealth, market integration) or social (religious behaviors, environmental values, social capital) factors are better indicators of environmental behavior. I used multilevel modeling to analyze use of fuelwood, use of agricultural chemicals, and tree planting, and to determine whether social norms were associated with these behaviors. Although economic factors were more often associated with these behaviors than social factors, local conditions and control variables were the best indicators of behaviors. Furthermore, economic factors were not always associated with positive environmental outcomes. Instead, farmers attempted to make the best economic decisions given their circumstances rather than seeking to conserve resources. Although religion was not a strong predictor of any of the behaviors I examined, I found evidence that the understanding of Buddhist philosophy is growing, which suggests that social factors may play a more prominent role as Bhutan's development progresses. My results highlight the need for conservation planners to be aware of local conditions when planning and implementing policies aimed at motivating environmental behaviors and that economic and social motivations for conservation may not be mutually exclusive.  相似文献   

14.
When the relationship between emissions and ambient pollution is known, it is possible to implement a program to achieve economically efficient pollution levels, even when the control agency knows nothing about the victim's valuation of pollution damages or about emission abatement costs. Unlike a Pigouvian tax, the program provides the correct incentives for entry and exit whether or not marginal damages from a firm's emissions vary over the range of these emissions. Through the provision of “missing” markets, sizable revenues are raised while allocative distortions are corrected.  相似文献   

15.
Spinach plants were contaminated with hexachlorobenzene (HCB) and 2,2′, 5,5′-tetrachlorobiphenyl (PCB) in the vapor phase and by bentonite aerosol. To characterize the deposition of these substances on contaminated plant leaves, different solvents were used (water,n-hexane, and acetone). The solubility of the substances was shown to depend on the mode of application. Release studies indicate that the concentration of the tested chemicals decreases to 5% for HCB and to 27%, respectively 49%, for PCB after a period of 4 days at 23°C for different modes of contamination.  相似文献   

16.
The effects of changes in amenity levels on the bid prices for land and on the marginal worth of an amenity are examined. The vehicle for analysis is a closed-city urban spatial model containing an explicit utility function and explicitly specified, spatial distributions of amenities. Issues addressed include the behavior of bid price (and property value) schedules in response to amenity changes; the impact of such changes on the utility of renters, under conditions of both identical and disparate tastes; the effect of amenity changes on the amenity's schedule of marginal worth; and the relation of such a schedule in a closed city to that in an open city.  相似文献   

17.
The optimal adjustment process for an effluent charge is derived when the firm's response to the charge is uncertain. The optimal process is shown to exhibit the dual effects of caution and probing. Because of uncertainty, society should be risk averse or cautious when setting the charge. However, because of the possibility of generating information for improved future control, this caution is balanced by the incentive to probe for additional information. Finally, if the uncertain parameters of the firm's response function are nonautonomous, their change over time must be explicitly considered to avoid bias in estimation.  相似文献   

18.

Objective and Background

PCB (polychlorinated biphenyle) are typical man-made environmental pollutants that cause a broad spectrum of effects in vertebrates. Although a lot has been studied about the toxic effects of xenobiotic substances on aquatic organisms, their subacute effects are not yet well known. Fish occupies a central position in freshwater food webs and therefore, carp was chosen to be our test organism. The aim of our study was the investigation of subacute effects of Aroclor 1254 (22μg l?1) on respiration, swimming activity, and biotransformation, allowing discussion of changed interaction between the available energy resources.

Methods

The respiration experiments under controlled laboratory conditions were run for 29 days (5 d before, 16 d with and 8 d after chemical exposure) with exposed carp compared to the non-exposed fish. Furthermore, the BehavioQuant system quantitatively monitors the positions of each individual fish before (8 d) and during (21 d) PCB exposure and swimming activity (number of horizontal turnings s?1) of animals was calculated. Thereafter, liver samples were taken from animals for analysis of the phase 2 enzyme activity (glutathione-S-transferase). In the respiration experiments were 6 exposure, 6 controll, and 3 solubilizer controll groups (12 animals each group); in the behavioral experiments were 9 exposure, 6 controll- und 3 solubilizer controll groups (6 animals each group), and in the enzyme activity measurements were 9 exposure, 6 controll and 3 solubilizer controll groups (6 animals each group) examined.

Results and Discussion

A clearly increased (33%) oxygen consumption due to the PCB-exposure is found to be reversible; after the exposure period the respiration of carp shows a level comparable to the oxygen consumption during non-exposure time. By evaluating quantitative behavioral parameters of animals, it becomes evident that the exposure to PCB also causes a reversible change in their swimming behavior. Chemical stress leads to a decrease of mean daily swimming activity combined with an increase of the mean number of turnings during the night. Thereafter, the swimming activity shifts to the circadian swimming behavior under control conditions. Furthermore, our measurement of soluble and microsomal glutathione-S-transferase activity of fish liver shows a significant elevation after exposure period.

Conclusion

Our results prove that it was feasible to detect sublethal effects of PCB-mixture on all parameters under these conditions successfully. Our findings imply that fish are able to cope with the chemicals and we purse the hypothesis that the higher physiological energy demand caused by increased activity of enzymes, which are involved in biotransformation of foregin substances, may be related to a higher respiration of fish stressed by xenobiotics.

Recommendation and Outlook

Further experiments should investigate the effects of PCB on ecophysiological parameters of carp fed with exposed natural food allowing discussion of ecological consequences.  相似文献   

19.
The paper opens with an assessment of natural resources economics up to 1913–14 when Gray published his two pioneering articles in natural resources economics (Part I). An in-depth study of Gray, weighing his contribution to the microeconomic theory of the mine and the macroeconomic theory of conservation against current literature, constitutes the main body of the paper (Part II). Gray and Hotelling's contributions to the theory of the mine are compared (Part III). The paper concludes with a comparison drawn between the author's findings and the scant attention previously paid to Gray's contributions to natural resources economics.“So far as I know, this is the first attempt to apply economic theory to this particular problem of conservation.” (H. C. Taylor, unpublished letter to C. R. Van Hise, May 23, 1913, a reference to Gray's “Economic Possibilities of Conservation”).  相似文献   

20.
The time-dependent characteristics of the five weather variables which control the annual thermal response of Lake Ohrid are analyzed in detail. These are daily values for solar radiation, air temperature, humidity, wind speed and cloud cover. A simple numerical model of the lake's thermal response, forced by thermally driven density mixing, is developed and tested using observed thermal profiles for verification. The numerical model successfully reproduces the major features of the lake's thermal regime over a 6 y period from 1972 to 1977, the average root mean square value for the simulated profiles being 1.2°C with extremes of 2.2 and 0.3°C and a standard deviation of 0.4°C.  相似文献   

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