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431.
This paper presents a method for assessing a community's sustainability prospects at a point in time. It argues that an improved methodology is needed to support the development of local area indicators. The method presented is community sustainability auditing. The ethical, conservative, competitive and co-operative aspects of sustainability are emphasized.The method uses an indicator approach within a protocol loosely inspired by International Standards Organization procedures. This involves the development of a set of questions for audit purposes, definition of indicators, analysis of the indicators in the light of the questions and a report summarizing a community's sustainability prospects.  相似文献   
432.
ABSTRACT A dynamic mathematical model was constructed to examine bacterial contamination problems affecting Ford Lake, a small recreational lake in Southeast Michigan. The model was calibrated and verified using summer dry weather averaged data and data from three wet weather surveys. Model simulations demonstrated that the major bacterial contamination was attributable to storm related perturbations affecting two point sources: the Huron River and the Ypsilanti Sewage Treatment Plant. The nonpoint source contribution was relatively minor. The Model is currently being used by the State of Michigan Department of Natural Resources as a management tool for assessing the effectiveness of planned pollution abatement strategies  相似文献   
433.
Determining reference concentrations in rivers and streams is an important tool for environmental management. Reference conditions for eutrophication-related water variables are unavailable for Brazilian freshwaters. We aimed to establish reference baselines for São Paulo State tropical rivers and streams for total phosphorus (TP) and nitrogen (TN), nitrogen-ammonia (NH4 +) and Biochemical Oxygen Demand (BOD) through the best professional judgment and the trisection methods. Data from 319 sites monitored by the São Paulo State Environmental Company (2005 to 2009) and from the 22 Water Resources Management Units in São Paulo State were assessed (N = 27,131). We verified that data from different management units dominated by similar land cover could be analyzed together (Analysis of Variance, P = 0.504). Cumulative frequency diagrams showed that industrialized management units were characterized by the worst water quality (e.g. average TP of 0.51 mg/L), followed by agricultural watersheds. TN and NH4 + were associated with urban percentages and population density (Spearman Rank Correlation Test, P < 0.05). Best professional judgment and trisection (median of lower third of all sites) methods for determining reference concentrations showed agreement: 0.03 &; 0.04 mg/L (TP), 0.31 &; 0.34 mg/L (TN), 0.06 &; 0.10 mg-N/L (NH4 +) and 2 &; 2 mg/L (BOD), respectively. Our reference concentrations were similar to TP and TN reference values proposed for temperate water bodies. These baselines can help with water management in São Paulo State, as well as providing some of the first such information for tropical ecosystems.  相似文献   
434.
Polyacrylamide (PAM) treatment of irrigation water is a growing conservation technology in irrigated agriculture in recent years. There is a concern regarding the environmental impact of PAM after its application. The effects of anionic PAM on the sorption characteristics of four widely used herbicides (metolachlor, atrazine, 2,4-D, and picloram) on two natural soils were assessed in batch equilibrium experiments. Results showed that PAM treatment kinetically reduced the sorption rate of all herbicides, possibly due to the slower diffusion of herbicide molecules into interior sorption sites of soil particles that were covered and/or cemented together by PAM. The equilibrium sorption and desorption amounts of nonionic herbicides (metolachlor and atrazine) were essentially unaffected by anionic PAM, even under a high PAM application rate, while the sorption amounts of anionic herbicides (2,4-D and picloram) were slightly decreased and their desorption amounts increased little. The impact mechanisms of PAM were related to the molecular characteristics of PAM and herbicides. The negative effects of PAM on the sorption of anionic herbicides are possibly caused by the enhancement of electrostatic repulsion by presorbed anionic PAM and competition for sorption sites. However, steric hindrance of the large PAM molecule weakens its influence on herbicide sorption on interior sorption sites of soil particles, which probably leads to the small interference on herbicide sorption, even under high application rates.  相似文献   
435.
ABSTRACT. Middle and high management levels within water utilities would find their decision making activities greatly enhanced if provided with a set of techniques having the following characteristics: (1) the ability to procure information and knowledge about real-life systems, (2) the ability to promote analysis of the real life system and (3) the capacity to gauge the impact of decisions. A model/simulation is presented, having the capability to mime operational aspects of water supply systems. The simulation produces time series of what are considered relevant operational variables. These series are amenable to analysis of both static and dynamic effects of alternative policies, changing environmental conditions and varying parametric specifications. Because of its modular structure and the ad hoc programming language utilized, it offers great flexibility. The model/simulation allows extensions, deletions and modifications without consequent reformulation or extensive reprogramming. It performs a number of statistical tests useful for its own verification and validation. Also available are a suggested methodology and procedures for model use, possible difficulties with data gathering and operation, plus an idea of what cannot be done with the currently extant model version.  相似文献   
436.
Environmental policies in the developing countries are the product of circumstances quite different from those found in advanced nations. As a result, such policies have thus far been rather permissive. There is, however, considerable variance among developing countries in this respect, as well as substantial change over time. Not much evidence has been uncovered pointing to a migration of industry and mining to ‘pollution havens’ in developing countries—the reverse in fact seems to be the case. Nevertheless, it is likely that environmental policies will remain less stringent in developingthan developed countries for the foreseeable future. Indeed, the gap may well widen substantially.  相似文献   
437.
For the past 11 years the annual Shellfish Biology Seminar at Milford CT has provided a unique forum for aquaculture scientists and industry officials to exchange information about estuaries facing increased pollution problems, especially Long Island Sound and the Great South Bay. Because these two areas are so rich in productivity and diversity, fish and shellfish farmers utilize their waters, shellfish beds, and shore land for hatcheries and grow-out facilities. These individuals seek better management of the coastal estuarine environment and its resources, providing a working example of environmental stewardship. In aquaculture, good science is required to understand the complex variables and interaction of estuarine currents, tides, temperature, and cycles of reproduction. Aquaculturists are beginning to understand the need for specific nutrients and how the wastes of one species can be utilized for enhanced production of another species. Over the years, this meeting has formed an amalgam of both the aquaculture industry and research scientists where both groups foster mutual environmental concern. Science is able to focus on the theoretical aspects of pollutant damage. while the aquaculture industry is able to define the problem and need for assistance to eliminate pollutants from their crops—shellfish and finfish. Overfishing is not an issue at these meetings, as the group accepts the damage already done to wild resources and seeks new technologies to grow food sources under controlled and stable market conditions. Therefore, it could be said that the seminar serves as a meeting ground where the theoretical knowledge of scientific study finds practical application in the industry and is fueled by the needs of that industry. This ideal blend of the two groups produces better management of the resource and a safer environment—the goal of stewardship.  相似文献   
438.
Concentrations of potential pollutant elements Na, Cl, and S were investigated in needles of Pinus canariensis grown at 55 field plots in Tenerife. Microelement concentrations (including heavy metals) were measured at a subset of 18 plots. Na and Cl concentrations were high at low elevations (up to 8 mg g(-1) Cl and 5.5 mg g(-1) Na). Na/Cl ratio close to standard seawater indicated sea spray influence up to 1200 m a.s.l. Only at few plots, sulphur concentrations indicated possible pollutant impact. Cluster and correlation analyses identified a related group of V, As, Cr, Fe, Mo, Ni, Cu, Pb, and Al, possibly related to traffic exhaust aggregated with soil particles. Mainly north-eastern, lower elevated plots were exposed to those immissions, but metal concentrations were generally low compared to data from other studies. In conclusion, seawater and soil particles explained most of the element distribution pattern in pine needles in Tenerife, but strong indications for some effect of local sources of air pollutants were detected.  相似文献   
439.
Seitz W  Jiang JQ  Schulz W  Weber WH  Maier D  Maier M 《Chemosphere》2008,70(7):1238-1246
The present work describes the investigation of the formation of oxidation by-products of the iodinated X-ray contrast medium (ICM) iomeprol during ozonation in water treatment. Bench-scale investigations revealed that ICM can be partly oxidized during ozonation processes, whereas the ionic diatrizoic acid showed the lowest reactivity. Iomeprol, as a representative of ICM, was not fully mineralized during ozonation. Thus, unknown oxidation by-products were formed. Aqueous solutions of iomeprol were treated by ozonation in order to assess the formation of oxidation by-products. The by-products were characterized by different liquid chromatography methods including detection of single-stage mass spectra, product ion mass spectra, and induced in-source fragmentation for analysis of iodine containing oxidation by-products. Aldehyde and carbonyl containing compounds were proposed to be among the stable by-products. A derivatization step confirms that the aldehyde and carbonyl moieties are major functional groups in oxidation by-products of iomeprol. Furthermore, oxidation by-products of iomeprol were detected at the outlet of an ozone reactor at a full-scale waterworks. However, the toxicological relevance of the by-products is a major future research tasks.  相似文献   
440.
Polybrominated biphenyls (PBBs) have been introduced as flame retardants in 1970. Despite decreasing application rates since the mid-1970s, PBB residues are still reported in the environment. Furthermore, environmental PBB residues often do not match the PBB pattern in technical products. To get insights into the structures of environmentally-relevant PBBs, the congener patterns of technical hexabromobiphenyl (THBB), octabromobiphenyl (TOBB), synthesized PBB 209 were compared to PBB residues in a cod liver sample from the Baltic Sea. The most relevant PBB congeners in Baltic cod liver were not present in the technical products and therefore most likely metabolites. For this reason, TOBB and HPLC-fractions obtained from this technical product were incubated with super-reduced cyanocobalamine. Reductive debromination was found to be the predominant transformation process. Bromine substituents in ortho-positions proved to be more recalcitrant, and several of the unknown PBBs were tri- and tetra-ortho substituted congeners. Furthermore, the key-PBBs determined in Baltic cod liver were formed during this process. The most important hexabromobiphenyl in Baltic cod liver was identified as PBB 155 by parallel synthesis. PBB 155 which was not detected in the technical PBB product analyzed was suggested as an indicator PBB congener suited to decide whether PBB residues originate from the previous use of THBB (low relative abundance of PBB 155) or TOBB/TDBB (high relative abundance of PBB 155). The latter scenario was found to be valid for the Baltic cod liver sample. Thus, PBBs in the Baltic Sea appeared to originate from partially-weathered residues of PBB 209.  相似文献   
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