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1.
The applicability of decision analysis for assessing, evaluating, and reporting possible environmental impacts of proposed large-scale projects is illustrated. A study concerning the ecological impacts of constructing and operating nuclear power facilities in the Pacific Northwest is used as an example. Possible impacts are quantified for two objectives: minimizing adverse impacts on salmonids and minimizing biological disturbance. The results provide information about both the direct and indirect consequences of the impact. This approach explicitly addresses the multiple objective and uncertainty issues inherent in environmental problems. It also provides a mechanism for illuminating the value structure which is utilized in the evaluation process. 相似文献
2.
利用1960—2009年的年月平均气温观测资料,分析了被检站和参考站的年、季变化趋势特点,着重研究了大型火电厂的热排放对当地气温的影响程度和相对贡献比例。从增温趋势看,被检站和参考站年平均气温增温速率分别为0.33~0.48℃?10a和0.21~0.33℃?10a,年热排放增温率为0.11~0.20℃?10a。热排放引起的四季增温速率为春秋强,冬季次之,夏季最小。火电厂的热排放对当地气温增温的贡献显著,表现为夏季最大,春秋季次之,冬季最小,对年平均气温序列的增温贡献率为31%~49%。 相似文献
3.
选择具有典型代表性的宁夏西大滩碱化土壤,采用拉丁方田间试验设计进行脱硫石膏改良碱化土壤种植水稻(Oryza sativa)的施用量研究.试验研究表明施用脱硫石膏能够降低土壤碱化度、总碱度和pH值,提高水稻的出苗率和产量.但是,脱硫石膏施用量不同,土壤碱化度、总碱度和pH值降低的值不同.根据脱硫石膏施用量与土壤碱化度、总碱度、pH值降低的模拟曲线关系,当脱硫石膏施用量为2.8~3.1kg·m~(-2)时,土壤碱化度、总碱度、pH值降低的值达到最大.同时,根据脱硫石膏施用量与水稻出苗率和产量的模拟曲线关系,当脱硫石膏施用量为2.86kg·m~(-2),水稻出苗率达到最大,为84.7%;当脱硫石膏施用量为2.79kg·m~(-2)时,水稻产量达到最大,为0.75kg·m~(-2).因此,建议脱硫石膏改良碱化土壤种植水稻的施用量为2.8~3.1kg·m~(-2). 相似文献
4.
This study was carried out to determine the possible effects of the Afsin-Elbistan Coal Power Plant (AECPP) on the environment.. The soil and plant samples were collected, based on the dominant wind direction, which is from northeast to southwest and we defined the northeast part of the plant as the less contaminated direction (LCD) and the southwest part as the more contaminated direction (MCD). The results indicated that the AECPP created environmental problems and caused contaminations especially in the MCD. The results of the statistical analysis for the measured attributes between the LCD and the MCD showed that there were significant differences for pH, SO4(-2)-S, Ni and Pb. Significant correlations were found between the distance from the AECPP and some of the measured soil and plant parameters in the MCD. The concentrations of SO4(-2)-S, Ni and Pb decreased as the distance increased. The discharge water carries a potential risk for the aquatic life and soil health in the area. The honey quality was also affected negatively by fly ash and emission. 相似文献
5.
We consider the problem of designing a surveillance system to detect a broad range of invasive species across a heterogeneous
sampling frame. We present a model to detect a range of invertebrate invasives whilst addressing the challenges of multiple
data sources, stratifying for differential risk, managing labour costs and providing sufficient power of detection. We determine
the number of detection devices required and their allocation across the landscape within limiting resource constraints. The
resulting plan will lead to reduced financial and ecological costs and an optimal surveillance system. 相似文献
6.
Reasons for the current siting impasse, including participatory activism, regulatory failure, the multiplication of considered interests, and the “investigative caveat,” are reviewed, and the existing logic of regulator behavior, viewed as a rational choice model, is summarized. Three sets of goals for agency participants are identified: personal goals of agency decision-makers, organizational goals of the agency as a whole, and goals of agency clients; and the incentive system of a new administrative agency structured so as to make satisfaction of these goals contribute toward informed and impartial decision-making. Major structural components of the agency would be a Director, a Corps of Examiners, counsel(s) for special interest(s) of special merit, a Public Counsel, and a Research and Information Office. The model is applied to the case of a regional or state-level agency to handle power plant siting. 相似文献
7.
An understanding of the spatial distribution and contribution of a power plant to local soil contamination is important for the planning of soil use and prioritizing remedial actions for public safety. Consequently, the aim of this study was to map the spatial distribution of potentially hazardous elements (PHEs; Cu, Pb, Zn, Ni, Cr, Fe, Mn, Cd, As, and Se) in soils around a large (796 MW) coal-fired power plant in Brazil. For the purpose, 33 soil samples were collected in the area within a radius of approximately 17.5 km from the plant and subsequently analyzed for PHEs. The frequency and direction of winds were also obtained from a meteorological station in the region. The sampling area was divided into four quadrants (northwest: N-NW; northeast: N-NE; southeast: S-SE; southwest: S-SW), and there were significant negative correlations between the distance and the concentrations of Se in the S-SE quadrant and As in the S-SW and S-SE quadrants. There were positive correlations between distance from the plant and the concentration of Mn in the N-NE quadrant and the concentration of Cd in the S-SW quadrant. The dominant direction of the winds was N-NE. The indexes used in this study showed low-to-moderate enrichment factor, but detailed analysis of the dominant quadrant of the winds showed a correlation with higher concentrations in the soils closer to the power plant for at least seven of the PHEs analyzed, especially with regard to As. Therefore, we conclude that the distribution of the metalloid As can be used as a marker of the spatial distribution of contamination from the thermoelectric plant, but the dynamics of the other elements suggests that the presence of other sources of contamination may also compromise the quality of local soils. 相似文献
8.
Alluvial soils of valleys of the Danube and Mlave rivers represent priority development areas with favorable conditions for life, agriculture and tourism in eastern Serbia. Operation of the thermal power plant Kostolac results in the emission of potentially toxic pollutants into the air, water and land. The goals were to determine the soil pollution with inorganic pollutants using different pollution indices, to identify of the sources of pollutants by means of principal component analysis and the loading of each factor for individual element assessed by multi-linear regression analyses. Chemical characteristics of the studied area resulted in division of the area into four impact zones upon the distance from main pollutants (power plant blocks and ash disposal dumps). There was no established soil pollution with potentially toxic elements in bulk of the agricultural territory. Two principal components (PC1 and PC2) explained about 73% of variance. Three studied elements (As, Cu and Pb) showed anthropogenic origin of their most concentrations in soil, while other elements (Cd, Co, Cr, Ni and Zn) were of a natural (geological) origin. Single pollution index showed moderate pollution level by Ni. Integrated Nemerow pollution index showed low to no pollution levels, indicating slight ecological risk. There were no established limitations for agricultural production in the studied area, except for the only spot polluted by As due to the great flooding event in the studied year. 相似文献
9.
This study evaluates the effect of air pollution caused by cement plants on nearby residential areas and performs an exposure assessment of particulate matter (PM) and total Cr, Cr 6+, Pb, and Al. Further, the blood Cr levels of residents exposed to PM released by cement plants are also assessed. Nine buildings (eight residential and one elementary school building) close to cement plants were selected for this study, which were located in Pyeongtaek port, in west of Gyeonggi Province, South Korea. A total of 51 suspended particulate samples were collected at a flow rate of 2.0 L/min. Total Cr was more widely detected in residents’ houses and elementary schools. PM levels were higher at distances of 4.1 and 4.8 km than those at closer distances of 2.7 km. This was due to the influence of wind direction. The estimated mean blood level of Cr for the study participants was 3.80 μg/L, which is higher than levels estimated by other studies on Cr blood levels. Therefore, cement plants could cause an increase in total Cr and blood Cr levels in residential areas, and more continuous monitoring is necessary to better understand their impacts. 相似文献
10.
Improved understanding of the spatial dynamics of invasive plant species may lead to more effective land management and reduced future invasion. Here, we identified the spatial extents of nonnative cheatgrass (Bromus tectorum) in the north central Great Basin using remotely sensed data from Landsat MSS, TM, and ETM+. We compared cheatgrass extents in 1973 and 2001 to six spatially explicit landscape variables: elevation, aspect, hydrographic channels, cultivation, roads, and power lines. In 2001, Cheatgrass was 10% more likely to be found in elevation ranges from 1400 to 1700 m (although the data suggest a preferential invasion into lower elevations by 2001), 6% more likely on west and northwest facing slopes, and 3% more likely within hydrographic channels. Over this time period, cheatgrass expansion was also closely linked to proximity to land use. In 2001, cheatgrass was 20% more likely to be found within 3 km of cultivation, 13% more likely to be found within 700 m of a road, and 15% more likely to be found within 1 km of a power line. Finally, in 2001 cheatgrass was 26% more likely to be present within 150 m of areas occupied by cheatgrass in 1973. Using these relationships, we created a risk map of future cheatgrass invasion that may aid land management. These results highlight the importance of including land use variables and the extents of current plant invasion in predictions of future risk. 相似文献
11.
The effects of a coastal power plant on an outer estuarine bay ecosystem on the west coast of Florida were evaluated with measurements and an ecological model. Field measurements of community metabolism and biomass were taken from the thermally affected bay and from similar control bays. Model simulations were used to help understand these observations in terms of ecosystem structure and functioning.In the outer discharge bay the direct impact of the thermal plume was diluted and spread overlarge areas. The ecosystem developed structure and functions with lower biomass than in the control bays but with slightly faster rates of organic turnover. The productive turnover time of producer biomass during the summer was about 5 days in the discharge bay and about 6 days in the control bays. Power plant influence on total community metabolism was small with less than 10% difference in annual averages between the discharge and control bays (5.22 and 5.58 g O 2/m 2/day). The selection for faster metabolic turnover rates in the discharge by was evidenced by a dominance of plankton metabolism over benthic metabolism. The annual average gross planktonic production was around 3 g O 2/m 2/day in the discharge bay and around 2 g/m 2/day in the control bays.In the model, temperature served as a stimulant to both productivity and respiration. When the isolated effects of increased temperature were simulated the model responded with lower producer biomass and faster rates of organic turnover, as was found in field measurements. These simulations also showed increased nutrient recycling and indicated patterns of temperature-induced migrations. Since power plant operation affected water exchange in the bays, several levels of total water exchange were simulated. These simulations indicated the importance of water exchange as a stabilizing factor, especially for sensitive compartments with rapid turnover rates (i.e. plankton and phosphorus stocks). Simulations of the effects of future power plant units on the bay ecosystem showed no large changes in total metabolism but indicated larger effects of plankton entrainment mortality and temperature-induced migrations of larger organisms. 相似文献
12.
About 70% of the copepods entering the cooling water system of a nuclear power plant on northeastern Long Island Sound (USA) are not returned to the Sound in the effluent. Copepod mortalities are caused by the mechanical or hydraulic stresses of passage, although our experimental design could not determine whether heat or chlorination could cause mortality in the absence of mortality induced by hydraulic stress. After passing through the power plant, copepods sink rapidly (ca. 2.5 times faster than controls). This leads to an increase in concentrations of copepods suspended in the deep water (25 to 30 m) of the effluent pond. About half of the live copepods collected at the discharge and held in situ died within 3.5 days, and 70% died within 5 days, whereas only 10% of those from the intake died in 5 days. About 60% of the copepods observed suspended in deep water in the pond were dead. The copepod mortality caused by the power plant reflects the loss in secondary production occurring below about 270×10 3 m 2 of sea surface in Long Island Sound annually. This loss represents a reduction of about 0.1% in the annual secondary production over a 333 km 2 area of Long Island Sound adjacent to the power plant. Highest losses occurred during the spring (April, 1.4×10 6 g dry weight), the lowest in autumn (November, 45.8×10 3 g). If the same copepod loss rate exists for all power plants in Long Island Sound, then secondary production in 1.69×10 6 m 2, or 0.05% of the total copepod production may be lost annually. A comparison of the surface outflow from Long Island to Block Island Sound with the water entrained through Millstone Unit One, and the 70% copepod loss rate in the latter area, indicates that Unit One eliminates about 0.1 to 0.3% of the copepod production in eastern Long Island Sound. This calculation compares favorably with losses computed from production data. 相似文献
15.
Application of Probabilistic Risk Assessment (PRA) and Deterministic Risk Assessment (DRA) at a coking plant site was compared. By DRA, Hazard Quotient (HQ) following exposure to Naphthalene (Nap) and Incremental Life Cancer Risk (ILCR) following exposure to Benzo(a)pyrene (Bap) were 1.87 and 2.12 × 104. PRA revealed valuable information regarding the possible distribution of risk, and risk estimates of DRA located at the 99.59th and 99.76th percentiles in the risk outputs of PRA, which indicated that DRA overestimated the risk. Cleanup levels corresponding acceptable HQ level of 1 and ILCR level of 104 were also calculated for both DRA and PRA. Nap and Bap cleanup levels were 192.85 and 0.14mg.kg-1 by DRA, which would result in only 0.25% and 0.06% of the exposed population to have a risk higher than the acceptable risk, according to the outputs of PRA. The application of PRA on cleanup levels derivation would lift the cleanup levels 1.9 times for Nap and 2.4 times for Bap than which derived by DRA. For this coking plant site, the remediation scale and cost will be reduced in a large portion once the method of PRA is used. Sensitivity analysis was done by calculating the contribution to variance for each exposure parameter and it was found that contaminant concentration in the soil (Cs), exposure duration (ED), total hours spent outdoor per day (ETout), soil ingestion rate (IRs), the air breathing rate (IRa) and bodyweight (BW) were the most important parameters for risk and cleanup levels calculations. 相似文献
16.
The Huludao zinc plant in Liaoning province, northeast China was the largest in Asia, and its smelting activities had seriously
contaminated soil, water and atmosphere in the surrounding area. For the first time, we investigated the total mercury (THg)
content in maize, soybean, broomcorn, 22 vegetables, and the soil around their roots from eight sampling plots near the Huludao
zinc plant. THg contents of the seeds of maize, soybean, and broomcorn are 0.008, 0.006, and 0.057 mg kg −1, respectively, with the broomcorn being the highest, exceeding the maximum level of contaminant in food (GB2762-2005) by
4.7 times. The edible parts of vegetables are also contaminated with a range of mercury contents of 0.001–0.147 mg kg −1 (dry weight). THg contents in plant tissue decrease in the order of leaves > root > stalk > grain. Using correlation analysis,
we show that mercury in the roots of these plants is mainly derived from soil, and the uptake of gaseous mercury is the predominant
path by which the mercury accumulated in the foliage. The average and maximum mercury daily intake (DI) of adult around the
Huludao zinc plant via consuming vegetables are 0.015 and 0.051 μg/kg/d, respectively, and those of children are 0.02 and
0.07 μg/kg/d, respectively. The average and maximum weekly intakes of total mercury for adult are 2.1 and 7.1%, respectively,
of the provisional tolerable weekly intake (PTWI), and 2.8 and 9.7%, respectively, of the PTWI for children. 相似文献
17.
Upwelling effects of subsurface water on phytoplankton growth were evaluated by 9 simulated culture experiments of coastal upwelling. Particular attention was paid to the effects of nutrient enrichment on the surface phytoplankton by the upwelling of nutrient rich subsurface water and of the exposure of the subsurface phytoplankters to surface radiation. The following are the results obtained: the lag period of phytoplankton growth was inversely related to water temperature; the maximum yield of phytoplankton was proportional to the amounts of available initial nutrients; the specific growth rates of phytoplankton were a function of both the initial nutrient concentrations and water temperature; and the maximum specific growth rate was simply proportional to water temperature. According to the relations found, a simple equation is presented for the estimation of phytoplankton growth in a given upwelling. Succession of species in the phytoplankton assemblage in upwelled water mass was also taken into consideration. 相似文献
18.
Monitoring of population trends is a critical component of conservation management, and development of practical methods remains a priority, particularly for species that challenge more standard approaches. We used field-parameterized simulation models to examine the effects of different errors on monitoring power and compared alternative methods used with two species of threatened pteropodids (flying-foxes), Pteropus conspicillatus and P. poliocephalus, whose mobility violates assumptions of closure on short and long timescales. The influence of three errors on time to 80% statistical power was assessed using a Monte Carlo approach. The errors were: (1) failure to count all animals at a roost, (2) errors associated with enumeration, and (3) variability in the proportion of the population counted due to the movement of individuals between roosts. Even with perfect accuracy and precision for these errors only marginal improvements in power accrued (-1%), with one exception. Improving certainty in the proportion of the population being counted reduced time to detection of a decline by over 6 yr (43%) for fly-out counts and almost 10 yr (71%) for walk-through counts. This error derives from the movement of animals between known and unknown roost sites, violating assumptions of population closure, and because it applies to the entire population, it dominates all other sources of error. Similar errors will accrue in monitoring of a wide variety of highly mobile species and will also result from population redistribution under climate change. The greatest improvements in monitoring performance of highly mobile species accrue through an improved understanding of the proportion of the population being counted, and consequently monitoring of such species must be done at the scale of the species or population range, not at the local level. 相似文献
19.
This contribution to the International Congress on Production of Safe Water, Izmir, Turkey, 20–24 January, 2009, relates to
general aspects of a water supply undertaking rather than to particular technologies or chemistries for water treatment. The
paper offers a “creative problem solving” approach following Fogler and LeBlanc (Strategies for creative problem solving.
Prentice Hall, NJ, 1995) as a model for generating sustainable solutions when water quality and safety problems arise. Such a structured approach
presents a systematic methodology that can promote communication and goal-sharing across the inter-related, but often isolated
and dispersed, functions of water scientists and researchers, engineers, operations managers, government departments and communities.
A problem-solving strategy, or “heuristic”, invokes five main steps (define; generate; decide; implement; evaluate). Associated
with each step are various creative and enabling techniques, many of which are quite familiar to us in one form or another,
but which we can use more effectively in combination and through our increased awareness and practice. For example, taking
a fresh view of a problem can be promoted by a variety of “lateral thinking” tools. First-hand investigation of a problem
can trigger new thinking about the real problem and its origins. A good strategy implementation will always address each and every step (though not necessarily every possible technique) and will use them at various stages in the search for and implementation of solutions. The creative nature of our experience
with a problem-solving heuristic develops our facility to cope better with complex formal situations, as well as with less
formal or everyday problem situations. A few anecdotes are presented that illustrate some of the author’s experiences relating
to factors involved in safe water supply. Here, the term “factors” may signify people and organisations as agents, as well as meaning those aspects of a problem situation that need to be taken into account. 相似文献
20.
Invasive plant species can be controlled by introducing natural enemies (insect herbivores) from their native range. However, such introduction entails the risk that the introduced herbivores attack indigenous plant species in the area of introduction. Here, we study the effect of spillover of a herbivore from a managed ecosystem compartment (agriculture) to a natural compartment (non-managed) and vice versa. In the natural compartment, an indigenous plant species is attacked by the introduced herbivores, whereas another indigenous plant species, which competes with the first, is not attacked. The combination of competition and herbivory may result in extinction of the attacked wild plant species. Using a modelling approach, we determine model parameters that characterize the risk of extinction for a wild plant species. Risk factors include: (1) a high attack rate of the herbivores on the wild non-target species, (2) niche overlap expressed as strong competition between the attacked non-target species and its competitor(s), and (3) factors favouring large spillover from the managed ecosystem compartment to the natural compartment; these include (3a) a high dispersal ability, and (3b) a moderate attack rate of the introduced herbivore on the target species, enabling large resident populations of the insect herbivore in the managed compartment. The analysis thus indicates that a high attack rate on the target species, which is a selection criterion for biocontrol agents with respect to their effectiveness, also mitigates risks resulting from spillover and non-target effects. While total eradication of an invasive plant species is not possible in the one-compartment-one-plant-one-herbivore system, natural enemy spillover from a natural to a managed compartment can make the invasive weed go extinct. 相似文献
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