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1.
Recent theoretical papers by Adar and Griffin (J. Environ. Econ. Manag.3, 178–188 (1976)), Fishelson (J. Environ. Econ. Manag.3, 189–197 (1976)), and Weitzman (Rev. Econ. Studies41, 477–491 (1974)) show that,different expected social losses arise from using effluent taxes and quotas as alternative control instruments when marginal control costs are uncertain. Key assumptions in these analyses are linear marginal cost and benefit functions and an additive error for the marginal cost function (to reflect uncertainty). In this paper, empirically derived nonlinear functions and more realistic multiplicative error terms are used to estimate expected control and damage costs and to identify (empirically) the mix of control instruments that minimizes expected losses.  相似文献   

2.
Macrozooplankton/micronekton in the epipelagic zone (0–100 m) of the NW Weddell Sea were sampled with a 10 m2 multiple opening-closing net environmental sampling system (MOCNESS) trawl during three cruises in 1995 and 1996. A total of 40 species were collected during all cruises. Community composition, as measured using Bray-Curtis analysis and multi-dimensional scaling, permitted separation into two groups: group 1 included samples collected during September–October 1995 and group 2 contained samples collected during April-May 1996 and November–December 1996. Zooplankton collections were dominated by Thysanoessa macrura in September–October 1995 (high pack-ice cover) and by both Euphausia superba and Salpa thompsoni in April–May 1996 (intermediate pack-ice cover) and November–December 1996 (open water). Copepods were not sampled quantitatively by the MOCNESS trawl and were not included in this analysis. Trends in measured parameters of community structure are discussed with respect to environmental characteristics during each sampling period.Communicated by P.W. Sammarco, Chauvin  相似文献   

3.
Pollution havens and industrial agglomeration   总被引:3,自引:0,他引:3  
This paper examines the pollution haven hypothesis using a spatial-economy model of two countries and two sectors. The manufacturing sector generates cross-border pollution which reduces cross-sectoral productivity of agricultural goods, and lowers local income. We derive a demand-reducing effect that discourages firms to move to the country with laxer environmental regulations, in the absence of any comparative advantage. Our analysis also demonstrates that manufacturing agglomeration forces can alleviate the pollution-haven effect: a pollution haven may not arise if environmental regulation is slightly more stringent in the larger country.  相似文献   

4.
The pattern of growth (biomass accumulation) in Ecklonia radiata throughout the year and across a depth profile was investigated using the traditional hole-punch method, and the information presented in context with concurrently measured in situ net productivity rates. The rate of net daily productivity showed a lack of consistent seasonal variability, remaining constant throughout the year at two of the four depths measured (3 m and 12 m), and becoming higher during winter at another (5 m). Throughout the year, rates of net daily productivity differed significantly across the depth profile. Net daily productivity rates averaged 0.017 g C g–1 dwt day–1 and 0.005 g C g–1 dwt day–1 at a depth of 3 m (1,394 mol O2 g–1 dwt day–1) and 10 m (382 mol O2 g–1 dwt day–1) respectively. In contrast, the biomass accumulation rate of E. radiata was highly seasonal, with low rates of growth occurring in autumn (0.002 g dwt g–1 dwt day–1 at both 3 and 10 m) and summer (0.007 and 0.004 g dwt g–1 dwt day–1 at 3 and 10 m respectively) and higher rates in spring (0.016 and 0.007 g dwt g–1 dwt day–1 at 3 and 10 m respectively) and winter (0.015 and 0.008 g dwt g–1 dwt day–1 at 3 and 10 m respectively). The proportion of assimilated carbon used for biomass accumulation varied throughout the year, between 5% and 41% at 3 m and between 28% and 128% at 10 m. The rates of biomass accumulation at all depths represented only a small proportion of the amount of carbon assimilated annually.Communicated by P.W. Sammarco, Chauvin  相似文献   

5.
Bleaching (visible loss of symbiont color) in populations of the diatom-bearing foraminifer Amphistegina has been recorded from reefs worldwide since 1991. Field studies and previous laboratory experiments have strongly implicated solar radiation as a factor in bleaching stress. The influence of spectral quality and quantity of photosynthetically active radiation (PAR) and ultraviolet radiation (UV) on growth rates and bleaching in Amphistegina gibbosa was investigated in the laboratory using fluorescent sources of PAR (blue with a spectral peak at 450 nm and white with a 600-nm spectral peak) and biologically effective ultraviolet radiation [UVB (280–320 nm)]. Growth rate, as indicated by increase in maximum shell diameter, saturated at a PAR of 6–8 mol photon m–2 s–1, increased in blue light, and was not influenced by UVB0.0162 W m–2. Frequency of bleaching increased with increasing PAR photon flux density and with exposure to shorter wavelengths, with or without an increase in total energy. Growth was significantly inhibited by UVB at 0.105 W m–2. Specimens in treatments exposed to UVB to PAR ratios >0.003 became dark in color, rather than bleaching, which previous cytological studies indicate is a photo-protective response. Implications of these experiments are that environmental factors that affect either the spectral quality or quantity of solar radiation can influence bleaching in Amphistegina.Communicated by P.W. Sammarco, Chauvin
Dana E. WilliamsEmail: Phone: +1-305- 3614569Fax: +1-305-3614499
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6.
Direct observations of the plankton vertical distribution performed from a manned submersible were made in the Charlie-Gibbs Fracture Zone (Atlantic Ocean). Plankton was counted using a standard 3-m2 frame in the depth layer from 170 to 4361 m and plotted for every 50 m. The most abundant components of the macroplankton were pelagic shrimps, chaetognaths and gelatinous animals, with peak of densities corresponding to the main pycnocline. Mucous houses of appendicularians were abundant at 150 m above the seabed—up to 0.07–0.09 m–3, compared to 0–0.006 m–3 in the upper layers. The new observations confirm that the near-bottom peak of appendicularian abundance is characteristic of at least the entire Central Atlantic, and it is not associated with certain biotopes on the bottom.Communicated by O. Kinne, Oldendorf/Luhe
G. M. VinogradovEmail:
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7.
This paper proposes a positive theory of environmental instrument choice. We study a democratic society that seeks to lower the level of pollution from industrial sources to a pre-specified target. The target can be implemented by one of three instruments: [S]: uniform emission standards; [P]: tradeable permits; and [T]: emission taxes. The conflict of interest between special-interests, representing polluters, and the electorate is resolved by an elected politician. We characterize when each of the three policy instruments is chosen in political equilibrium and show that the transition, observed in many countries, from [S] to either [P] or [T] can be understood as a natural consequence of increasingly ambitious environmental targets.  相似文献   

8.
Turner  E. J.  Miller  D. C. 《Marine Biology》1991,111(1):55-64
Experiments were conducted in April–August 1989 on juvenileMercenaria mercenaria (L.) in an oscillatory water tunnel to simulate resuspension of bottom sediments by waves and to determine the effects of shortterm storm events on particle ingestion, pseudofeces production, and shell growth. Juveniles (mean length = 19.2 mm) were subjected to identical concentrations of algae in both low-flow, gentle waves (maximum velocity = 7 cm s–1) and high-velocity storm waves (maximum velocity = 22 cm s–1). Suspended sediment levels reached 193 mg 1–1 at 1 cm above the bed during storms. Shell growth decreased by a maximum of 38% during the storm when levels of phytoplankton were high (average cell concentration = 43 × 106 cells 1–1), and by 18% when phytoplankton levels were low (av cell conc = 6 × 106 cells 1–1). Orientation of clam siphons was not related to flow direction. Significantly more pseudofeces were produced when the clams were subjected to increased sediment resuspension under waves, and in troughs of sand ripples. The size of sediment grains ingested did not vary significantly among the flow treatments. The decrease in shell growth during storms may be due to a reduction in filtration rate coupled with a decrease in net energy gained from filtration due to costs of pseudofeces production. The magnitude of the decrease seems to be related to concentration of algae, water temperature, age of clams and sediment transport mode (bed load or suspended load). Thus, the interpretation of growth increments must be made in the context of these environmental variables.  相似文献   

9.
This paper investigates privately and socially optimal patterns of economic development in a two-sector endogenous growth model with clean and dirty goods. We consider a second-best fiscal policy framework in which distortionary taxes jointly influence economic growth and environmental quality. In this policy setting, three conditions produce an Environmental Kuznets Curve (EKC): (i) dirty output is bounded; (ii) clean output grows endogenously; and (iii) growth in the dirty sector reduces growth in the clean sector. These conditions do not arise with a consumption externality, but can emerge with a production externality. Endogenous labor supply implications are also investigated. Although not necessary for producing an EKC, endogenous labor supply provides additional linkages that produce an EKC under circumstances in which it would otherwise not appear.  相似文献   

10.
We revisit one of the classical problems in geography and cartography where multiple observations on a lattice (N) need to be grouped into many fewer regions (G), especially when this number of desired regions is unknown a priori. Since an optimization through all possible aggregations is not feasible, a hierarchical classification scheme is proposed with an objective function sensitive to spatial pattern. The objective function to be minimized during the assignment of observations to regions (classification) consists of two terms: the first characterizes accuracy and the second, model complexity. For the latter, we introduce a spatial measure that characterizes the number of homogeneous patches rather than the usual number of classes. A simulation study shows that such a classification procedure is less sensitive to random and spatially correlated error (noise) than non-spatial classification. We also show that for conditional autoregressive error (noise) fields the optimal partitioning is the one that has the highest within-units generalized Moran coefficient. The classifier is implemented in ArcView to demonstrate both a socio-economic and an environmental application to illustrate some potential applications.
Tarmo K. Remmel (Corresponding author)Email:
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11.
Utilizing a price expectations model of wastepaper supplies Edwards [J. Environ. Econ. Manag.6, 332–334 (1979)] claims to be able to explain certain anomalies in earlier empirical work while reaffirming the view that wastepaper supply is generally price inelastic. This paper presents evidence to show that the price expectations model does not offer an adequate explanation of the state of affairs in the U.K. wastepaper market. The low price elasticity of supply findings are, however, confirmed.  相似文献   

12.
In their analyses of the impact of pollution taxation on the location of polluting decisions, U. K. Mathur (J. Environ. Econom. Management 3, 16–28 (1976)) and S. S. Gokturk (J. Reg. Sci. 19, 461–467 (1979)) obtained the result that a tax increase on urban pollution concentration may not succeed in pushing the polluting firm away from the urban center. In this paper is shown that the sufficient condition for success in this case depends upon the specification of the production and pollution emissions technology and may be the opposite to the one posited by Mathur and has more intuitive appeal.  相似文献   

13.
The population age structure and derived population dynamics (recruitment, growth and mortality), rhizome growth and flowering effort of Cymodocea nodosa in the Ria Formosa (south of Portugal) were examined using reconstruction techniques. The horizontal rhizome elongation rates were low (13.8–30.7 cm year–1), which is consistent with the low population growth rate (–2.35 to 0.29 year–1). The vertical elongation rate was proportional to the horizontal growth except for one stand that was subjected to sand movements and had higher elongation rates. The mean leaf production varied from 11.8 to 14 leaves year–1. The average shoot age varied from 0.70 to 1.04 years, and the oldest shoot found was 7.6 years. The mortality rates were the highest as yet reported for this species (0.99–3.70 year–1). Observed low growth and high mortality are possibly associated with the development of eutrophic conditions in the Ria Formosa. The flowering probability found in Ria Formosa stands (<0.009–0.90 shoots–1 year–1) was comparable to that found in the Mediterranean and off the Canary Islands. Only two stands with flowering events were found inthe Ria Formosa population, which indicates that the stands are highly dependent on clonal growth to maintain themselves inthe Ria Formosa.Communicated by O. Kinne, Oldendorf/Luhe  相似文献   

14.
Budget-Balancing Incentive Mechanisms   总被引:5,自引:0,他引:5  
A. P. Xepapadeas [J. Environ. Econom. Management20, 113-26, 1991] developed a pollution abatement incentive mechanism that both reduces the information requirements of a regulator and is "budget-balancing," drawing only on the social gains from pollution abatement to encourage firm compliance. This paper demonstrates that, contrary to Xepapadeas, the budget-balancing system of random penalties cannot be used to induce compliance with the regulator′s objectives if firms are risk neutral. However, the mechanism can be successfully applied if firms are sufficiently risk averse [E. Rasmusen, RAND J. Econom.18, 428-435, 1987].  相似文献   

15.
The daily abundance of aloricate ciliates at Lime Cay, Jamaica, a shallow neritic site, ranged from 29 to 118 × 106 m–2 (0.97 to 3.93 × 106 m–3) between November 1985 and November 1986. Biomass was converted to kilojoules (1 kcal=4.1855 kJ) assuming 42% carbon, 20.15 kJ (g dry wt)–1, and 20% cell shrinkage. Biomass ranged from 0.40 to 3.00 kJ m–2 (13.3 to 100 J m–3; 0.28 to 2.08µg C l–1) with an annual mean of 1.11 kJ m–2 (36.8 J m–3; 0.764µg C l–1). Nanociliates (<20µm equivalent spherical diameter, ESD) dominated abundance, but microciliates (> 20µm ESD) dominated biomass.Strombidium, Strobilidium, Tontonia andLaboea species were conspicuous taxa. Annual production estimates of the aloricate assemblage, based on literature growth rates, ranged from 404 kJ m–2 yr–1 (37 J m–3 d–1) to 1614 kJ m–2 yr–1 (147 J m–3 d–1). A compromise estimate of 689 kJ m–2 yr–1 (i.e., 63 J m–3 d–1) is comparable to other estimates from tropical and subtropical regions. A model of annual energy flow through 11 planktonic compartments suggests the total ciliate assemblage (aloricates and tintinnines) to be as productive as metazoan herbivores and metazoan carnivores.  相似文献   

16.
Firm incentives to promote technological change in pollution control: Reply   总被引:1,自引:0,他引:1  
Our paper (Firm incentives to promote technological change in pollution control, J. Environ. Econom. Management 17, 247–265 (1989)) concluded that firms will most actively search for new abatement technology under taxes and auctioned permits. However, Marin (Firm incentives to promote technological change in pollution control: Comment, J. Environ. Econom. Management, 21, 297–300 (1991)) argues that we overstated the efficacy of auctioned permits: that we used an unrealistic assumption which might affect our findings; that auctions may misallocate permits and are administratively burdensome; and that innovation detection is difficult under this regime. Here we show that our results are largely unchanged when the assumption questioned by Marin is relaxed. We also argue that he overstates the other concerns.  相似文献   

17.

Goal and Scope

Planning projects concerning the environment often provoke problems due to a lack of transparency of the applied scales and the appropriate evaluation methods. This paper therefore examines the general structure of all valuation processes before describing the character of the economic evaluation method in detail. From this point of view, requirements on planning processes are coming out which are to be achieved if their duty — the provision of public goods — is to be carried out efficiently.

Features

It will be shown that from an economist’s perspective a planning procedure acts as a surrogate of the market in coordinating individual’s preferences. The reasons for the inefficient level of the provision of environmental goods by private producers are their main characteristics: non-rivality and non-excludability; therefore public goods do not possess prices. Thus environmental goods have to be produced by cooperation and planning processes have to guarantee this. The main character of planning procedures is be seen in communication processes which is documented by a narrative study.

Results and Conclusions

Planning projects concerning the environment are strongly contingent on communication processes. Thus, they are also controllable by communication. The interdisciplinary research in communications shows that cooperative behaviour which is required for planning projects that should provide public goods can be benefited by applicative communication technologies. In this juncture (social) norms more and more emerge to act an important part in conveying cooperative behaviour. Especially so called ‘Sozialtechniken’ seem to be able to activate such norms.

Outlook

From the economist’s point of view planning projects concerning the environment mostly desiderate two things: Firstly, the procedures and methods which are applied to evaluate the regarding environmental goods in many cases suffer from transparency. Secondly, individual’s preferences predominant by the local population and accordingly by the directly involved parties are mostly not acquired adequately to achieve an efficient allocation of environmental goods. Applying more communication technologies to solve these two problems in the future both an increase of efficiency and an increase of the acceptability of such planning projects can be expected.  相似文献   

18.
Causes of Keshan–Beck disease (KBD) are still being probed and monitored in China. Relationships between trace elements from eco-environmental systems and KBD are poorly understood although relationships between environmental Se and human health have received extensive attention. In order to investigate relationships between eco-environmental geochemistry and KBD, we selected the Chousang KBD area in Yao County, Shaanxi Province, China, as an example of a prevailing KBD area applying I–Se-rich salts instead of utilizing Se-rich fertilisers on food crops to prevent local residents from developing KBD before 1995. Environmentally geochemical samples (rocks, soils, plants and children's hair) were collected from the Chousang KBD area. Soils in the study area contain 0.11±0.02 µg Se g–1, 0.75±0.11 µg Mo g–1, and 34.5±1.5 µg B g–1 on average, indicating that the study area is a deficient-Se–Mo–B area. Se (0.07±0.007 µg g–1), Mo (0.35±0.09 µg g–1) and B (3±0 µg g–1) contents are low in wheat and corn used as a daily main food staple of local inhabitants. It is indicated that the study area is deficient in environmental Se–Mo–B for the local residents. Se contents of children's hair from the Yangyuan Elementary School in the study area range from 0.09 to 0.26 µg Se g–1 with an average of 0.165±0.05 µg Se g–1 (n=10) in this KBD endemic area. Due to the low levels of Se, Mo and B available in soils and rocks, crops including wheat and corn are deficient in these elements, accordingly, the deficiency of Se, Mo and B in this area may be linked to the daily consumption of wheat and corn deficient in Se, Mo and B. Therefore, local inhabitants should be encouraged to fertilise mixtures of Se, Mo and B on crop plants in order to avoid development of KBD and guarantee a good harvest of crops.  相似文献   

19.
Participatory turnover time is defined as the time required to cycle an element in a system through a given material in that system. The participatory turnover time of ionic zinc by the adult Meganyctiphanes norvegica population in the Ligurian Sea ranged between 498 and 1243 years, depending upon the available food supply, and considering the food chain as the only route for zinc accumulation by the population. A total-impact turnover time was calculated as the sum of the participatory turnover time for live individuals plus the time required for dead euphausiids to lose 90% of their zinc to the water. Carcasses lost zinc to the water slower than either feces or molts, and so established the maximum loss time for all particulate excretion products; nevertheless, total-impact turnover time for zinc did not differ significantly from the participatory turnover time. The net vertical transport of zinc by M. norvegica from the sea surface to any specified depth can be calculated as the sum of the dissolved zinc excreted below the depth plus the concentrations of zinc left in feces, molts, and carcasses after they have sunk to the specified depth. Carcasses sink the fastest and lose the smallest fraction of their zinc concentration during descent; fecal pellets sink the slowest and lose the greatest fraction of their zinc concentration, and molts are intermediate. Nevertheless, feces represents the major route for delivering zinc to the bottom of the Ligurian Sea (2500 m), because concentration of the element in the pellets is so much higher than in carcasses or molts. Excretion of dissolved zinc into the water at the vertical migration depth of the living population during daylight hours was also inconsequential. Feces zinc represented over 80% of the total zinc transported to the sea floor if only marginal food supplies were available to the euphausiids, and over 90% if food was in sufficient supply. M. norvegica can effect a net transport of about 98% of its body zinc concentration below 500 m daily, in conditions of sufficient food supply and assuming that no released products are eaten during descent. If the food supply in the Ligurian Sea is considered only marginal throughout the year, M. norvegica can still effect a daily net transport below 500 m of about 36% of its body concentration, and about 6% of its body concentration will reach 2500 m daily.  相似文献   

20.
This investigation was carried out to determine the hydrogeochemical characteristics of the Kirkgeçit and Ozancik hot springs. The study areas are located northeast and southwest of the town of Çan, Çanakkale. During the investigation, geological maps of the hot springs and its surroundings were prepared, and hot waters and rock samples were collected from the study sites. The Paleogene–Neogene aged andesite, trachyandesite, andesitic tuff, silicified tuff and tuffites form the basement rocks in the Ozancik hot spring area. In the Kirkgeçit hot spring area, there are Lower Triassic aged mica and quartz schists at the basement rocks. The unit is covered by limestones and marbles of the same age. They are overlain by Quaternary alluvial deposits. A chemical analysis of the Kirkgeçit hot water indicates that it is rich in SO4 2– (1200.2 mg L–1), Cl (121.7 mg L–1), HCO3 (32.5 mg L–1), Na+ (494 mg L–1), K+ (30.2 mg L–1), Ca2+ (102 mg L–1), Mg2+ (15.2 mg L–1), and SiO2 (65.22 mg L–1). Chemical analysis of the Ozancik hot water indicates that it is rich in SO4 2– (575 mg L–1), Cl (193.2 mg L–1), HCO3 (98.5 mg L–1), Na+ (315 mg L–1), K+(7.248 mg L–1), Ca2+ (103 mg L–1), Mg2+ (0.274 mg L–1), and SiO2(43.20 mg L–1). The distribution of ions in the hot waters on the Schoeller diagram has an arrangement of r(Na++K+)>rCa2+>rMg2+ and r(SO4 2–)>rCl>r(HCO3 ). In addition, the inclusion of Fe2+, Cu2+, Cr3+, Mn2+, Ni2+ and Hg2+ in the hot water samples indicates potential natural inorganic contamination. The water analysis carried out following the ICPMS-200 technique was evaluated according to the World Health Organisation and Turkish Standards. The use and the effects of the hot water on human health are also discussed in the paper.  相似文献   

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