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931.
The Patagonian coast is considered a relatively pristine environment. However, studies conducted along coastal Patagonia have
showed hydrocarbon pollution mostly concentrated at ports that have fishing, oil loading, general merchant, and/or tourist
activities. A high value of total aliphatic hydrocarbons (TAH) was found at the Rawson fishing port (741 μg/g dw). In other
ports with and without petroleum-related activities, hydrocarbon values were approximately 100 μg/g dw. The highest values
for TAH and total aromatic hydrocarbons (TArH) were found in Faro Aristizábal, north of San Jorge gulf (1304 and 737 μg/g
dw, respectively). This is very likely the result of petroleum-related activities at the Comodoro Rivadavia, Caleta Cordova,
and Caleta Olivia ports located within this gulf. In other coastal areas away from potential anthropogenic sources, hydrocarbon
values were less than 2 and 3 μg/g dw for TAH and TArH, respectively. This review of published and unpublished information
suggests that ports are important oil pollution sources in the Patagonian coast. More detailed studies are needed to evaluate
the area affected by port activities, to understand the mechanisms of hydrocarbon distribution in surrounding environments,
and to assess bioaccumulation in marine organisms. Despite that some regulations exist to control oil pollution derived from
port and docked vessel activities, new and stricter management guidelines should be implemented. 相似文献
932.
Predicting Opportunities for Greening and Patterns of Vegetation on Private Urban Lands 总被引:1,自引:1,他引:1
Troy AR Grove JM O'Neil-Dunne JP Pickett ST Cadenasso ML 《Environmental management》2007,40(3):394-412
This paper examines predictors of vegetative cover on private lands in Baltimore, Maryland. Using high-resolution spatial
data, we generated two measures: “possible stewardship,” which is the proportion of private land that does not have built
structures on it and hence has the possibility of supporting vegetation, and “realized stewardship,” which is the proportion
of possible stewardship land upon which vegetation is growing. These measures were calculated at the parcel level and averaged
by US Census block group. Realized stewardship was further defined by proportion of tree canopy and grass. Expenditures on
yard supplies and services, available by block group, were used to help understand where vegetation condition appears to be
the result of current activity, past legacies, or abandonment. PRIZM™ market segmentation data were tested as categorical
predictors of possible and realized stewardship and yard expenditures. PRIZM™ segmentations are hierarchically clustered into
5, 15, and 62 categories, which correspond to population density, social stratification (income and education), and lifestyle
clusters, respectively. We found that PRIZM 15 best predicted variation in possible stewardship and PRIZM 62 best predicted
variation in realized stewardship. These results were further analyzed by regressing each dependent variable against a set
of continuous variables reflective of each of the three PRIZM groupings. Housing age, vacancy, and population density were
found to be critical determinants of both stewardship metrics. A number of lifestyle factors, such as average family size,
marriage rates, and percentage of single-family detached homes, were strongly related to realized stewardship. The percentage
of African Americans by block group was positively related to realized stewardship but negatively related to yard expenditures. 相似文献
933.
Using GIS to Generate Spatially Balanced Random Survey Designs for Natural Resource Applications 总被引:2,自引:0,他引:2
Theobald DM Stevens DL White D Urquhart NS Olsen AR Norman JB 《Environmental management》2007,40(1):134-146
Sampling of a population is frequently required to understand trends and patterns in natural resource management because financial
and time constraints preclude a complete census. A rigorous probability-based survey design specifies where to sample so that
inferences from the sample apply to the entire population. Probability survey designs should be used in natural resource and
environmental management situations because they provide the mathematical foundation for statistical inference. Development
of long-term monitoring designs demand survey designs that achieve statistical rigor and are efficient but remain flexible
to inevitable logistical or practical constraints during field data collection. Here we describe an approach to probability-based
survey design, called the Reversed Randomized Quadrant-Recursive Raster, based on the concept of spatially balanced sampling
and implemented in a geographic information system. This provides environmental managers a practical tool to generate flexible
and efficient survey designs for natural resource applications. Factors commonly used to modify sampling intensity, such as
categories, gradients, or accessibility, can be readily incorporated into the spatially balanced sample design. 相似文献
934.
Landscape characteristics and parcel ownership information are often collected on different spatial scales leading to difficulties in implementing land use plans at the parcel level. This study provides a method for aggregating highly resolute landscape planning information to the parcel level. Our parcel prioritization model directly incorporates a Land Trust's conservation goals in the form of a compromise programming model. We then demonstrate the use of our approach for implementation decisions, including parcel selection under a budget constraint and the estimation of a total conservation budget necessary to meet specific conservation goals. We found that these cost constraints significantly alter the composition of the 'best' parcels for conservation and can also provide guidance for implementation. The model's results were integral to a local Land Trust's ability to further define and achieve their goals. 相似文献
935.
The Environmental Management System (EMS) is commonly implemented in private firms. However, on the basis of a strengths, weaknesses, opportunities and threats (SWOT) analysis, our work analyzes the consequences of implementing an EMS within the context of local public administrations, particularly regarding the City Council of Ohanes in Almería (Spain). This is the first European corporation to implement an EMS according to the ISO 14001 Standard, certified by the Spanish Association of Normalization and Certification. Its analysis would be equivalent to the Shumpeterian "market innovator study", so that public administration "followers" can take advantage of the derived benefits and of minimizing the negative effects of such an experience. On the other hand, we show that the economic and environmental advantages derived from the EMS go beyond the activities that the City Council is in charge of. They have spillover effects that extend them to all economic activities in the municipality and these effects are expected to be increased in the medium and long-term perspective. In this paper, we compare the costs and benefits that the municipality obtains in two cases: the City Council implements the EMS or it does not implement it. The main objective of this article is to show the economic and environmental advantages obtained by a municipality when it is only the City Council who is implementing an EMS. It is logical to suppose that this case study can stimulate other municipalities to use this instrument, even if the economic and environmental characteristics of the municipality are different. 相似文献
936.
Computer display technology is currently in a state of transition, as the traditional technology of cathode ray tubes is being replaced by liquid crystal display flat-panel technology. Technology substitution and process innovation require the evaluation of the trade-offs among environmental impact, cost, and engineering performance attributes. General impact assessment methodologies, decision analysis and management tools, and optimization methods commonly used in engineering cannot efficiently address the issues needed for such evaluation. The conventional Life Cycle Assessment (LCA) process often generates results that can be subject to multiple interpretations, although the advantages of the LCA concept and framework obtain wide recognition. In the present work, the LCA concept is integrated with Quality Function Deployment (QFD), a popular industrial quality management tool, which is used as the framework for the development of our integrated model. The problem of weighting is addressed by using pairwise comparison of stakeholder preferences. Thus, this paper presents a new integrated analytical approach, Integrated Industrial Ecology Function Deployment (I2-EFD), to assess the environmental behavior of alternative technologies in correlation with their performance and economic characteristics. Computer display technology is used as the case study to further develop our methodology through the modification and integration of various quality management tools (e.g., process mapping, prioritization matrix) and statistical methods (e.g., multi-attribute analysis, cluster analysis). Life cycle thinking provides the foundation for our methodology, as we utilize a published LCA report, which stopped at the characterization step, as our starting point. Further, we evaluate the validity and feasibility of our methodology by considering uncertainty and conducting sensitivity analysis. 相似文献
937.
Although the use of kerbside recycling facilities by householders is often key to the reduction of materials disposed of to landfill, the quantitative assessment of householders' recycling behaviour is problematic. This study introduces a method to diagnose recycling behaviour by assessing kerbside scheme use in terms of the set-out of recyclate containers compared to the proportion of households participating in recycling (participation ratio). Application of numerical behaviour models demonstrated that kerbside recycling in sampled regions of the UK tends to be consistent with householders using kerbside schemes more frequently than would be observed with random patterns of use that are uniform amongst all householders. When aggregated to collection rounds, householders' modal recycling behaviour tended towards either non-participation or frequent participation. We propose that initiatives to enhance kerbside recycling should employ such quantitative assessments of recycling behavioural modes to inform and guide promotional and educational strategies. A conceptual model for prioritizing campaigns to promote recycling at the kerbside on the basis of identifiable and quantifiable patterns of householder recycling behaviour is presented. 相似文献
938.
Because the large rivers of the Seine watershed have a low microbiological water quality, the main sources of fecal contamination were investigated in the present study. The inputs of the point (wastewater treatment plants (WWTPs) effluents) and non-point sources (surface runoff and soil leaching) of fecal bacteria were quantified for Escherichia coli and intestinal enteroccoci used as bacterial indicators. In order to assess the contamination through non-point sources, fecal indicators abundance was estimated in samples collected in small streams located in rural areas upstream from all point sources; these small rivers were characterized by the land use of their watershed. Bacterial indicator numbers were also measured in effluents of WWTPs, some using classical treatment (settling followed by activated sludge process) and some using an additional disinfection stage (UV irradiation). These data were used to estimate the respective importance of each type of source at the scale of the whole Seine river watershed taking into account the land use and the population density. It shows the predominant importance of the point sources of fecal indicator bacteria at the scale of the whole watershed. In a scenario in which activated sludge treatment would be complemented with UV in all WWTPs located in this watershed, the non-point sources of fecal indicator bacteria would be dominant. 相似文献
939.
Response to environmental flows in the lower Tarim River, Xinjiang, China: ground water 总被引:1,自引:0,他引:1
In China's west since the 1950s large-scale ecosystem degeneration has occurred through water diversions for agricultural purposes. Since 2000, 1038 x 10(6) m(3) of water have been released into the Tarim River with the result that water reached the terminal Taitema Lake for the first time in 30 years. This environmental flow raised water-table levels along 350 km of the river. To assess the response of the water-table, a comparison "pristine" site is compared with downstream monitored sites. The results show huge changes in water-table levels. The study verifies that the water-table is extremely responsive to environmental flows, that strong internal similarities exist along the length of the river, and that the effect on the water-table and hence likely riparian vegetation recovery can be tentatively predicted. The actual impacts of the restoration strategy are less than those originally expected politically, socially and within the scientific community. We make recommendations on more effective release strategies. 相似文献
940.
Control of combustion-generated nitrogen oxides by selective non-catalytic reduction 总被引:7,自引:0,他引:7
Controlling nitrogen oxides (NO(x)) emissions is becoming a daunting technical challenge as increasingly strict emission limits are being imposed. The stringent regulations have prompted the innovation and characterization of NO(x) control technologies suitable for various applications. This paper presents a review on NO(x) removal techniques with particular reference to selective non-catalytic reduction (SNCR) technology. This includes initially how SNCR emerged as a technology along with a comparison with other relevant technologies. A review of various features related to selective non-catalytic gas phase injection of ammonia and ammonium salts (as reducing agent) is presented. The use of urea solution as a reducing agent and its performance in laboratory and pilot scale tests as well as large-scale applications is also discussed. Use of cyanuric acid as a potential reducing agent is also presented. The underlying reaction mechanisms have been reviewed for ammonia, urea and cyanuric acid for the explanation of various observations. Computational fluid dynamics (CFD) modeling as applied to SNCR is also presented. Subsequently the use of SNCR coupled with other in-combustion and post-combustion NO(x) control techniques is elaborated. Additionally, a two-stage NO(x) removal strategy to control un-reacted ammonia slip and to improve overall efficiency is discussed. At the end a summary is given which highlights various areas needing further research. 相似文献