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191.
192.
The establishment of high quality long-term monitoring programmes is essential if the implementation of the Water Framework Directive (WFD) is to be effective. It is recognised that monitoring can be very expensive and so guidance is needed to establish cost-effective, risk-based and targeted groundwater monitoring across Europe that enables WFD objectives to be met. In this context, the Groundwater Working Group (WGC) of the Common Implementation Strategy (CIS) of the WFD has developed recommendations aiming to implement consistent groundwater monitoring across Europe. This has been published on the internet in the form of a non-legally binding guidance document, which provides useful elements for the development and maintenance of networks at high standards and thereby provide the necessary information to assess (ground)water status, identify trends in pollutant concentrations, support establishment and assessment of programmes of measures and the effective targeting of economic resources. This paper presents this guidance document.  相似文献   
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194.
This article proposes a new theoretical framework that supports the preparation of local communities to deal with climate impacts.In this framework,derived from the metabolism model,the resources that form the input(social capital and practical conditions)for design charrettes are processed to deliver output resources in the form of enhanced and sophisticated spatial design propositions,which are more resilient en adaptive.Elaborating this model,processing input to deliver desired outputs can only occur when deep learning experiences are offered to the local community.The framework is used and tested in two case studies in northwest Victoria,the City of Bendigo and town of Sea Lake.The findings from the study show the performance of the framework and the improved properties of the design propositions.Conducting design charrettes has two effects.New ways of collaboration are explored allowing exchange to happen between community members with different interests.This leads to new social constructs that are capable of achieving results that would be otherwise impossible or unknown of.Secondly,the design propositions suggest highly resilient and adaptive spatial transformations in the city or town.  相似文献   
195.
    
Abstract

The overall purpose of this study was to assess whether interaction with a regionally based computer simulation software tool, Gb-Quest, was an effective tool for learning about sustainability. A questionnaire was administered to 189 participants, before and after attending a workshop on Gb-Quest. Factor analysis was used to determine the factor structure of the three scales used in this study. Seven variables were identified and were examined for group differences (gender, age, and whether or not they were Canadian born). In particular, younger individuals and males were more likely to endorse the view that the earth is being destroyed by humans. In addition, Canadian-born individuals were more likely to endorse the consumption of environmentally friendly products, but less likely to be supportive of development and using public transportation. We also examined change for each of the variables and found that Gb-Quest had an effect on all of them. Findings are discussed in terms of implications for future research.  相似文献   
196.
Genetic engineering evokes a number of objections that are not directed at the negative effects the technique might have on the health and welfare of the modified animals. The concept of animal integrity is often invoked to articulate these kind of objections. Moreover, in reaction to the advent of genetic engineering, the concept has been extended from the level of the individual animal to the level of the genome and of the species. However, the concept of animal integrity was not developed in the context of genetic engineering. Given this external origin, the aim of this paper is to critically examine the assumption that the concept of integrity, including its extensions to the level of the genome and the species, is suitable to articulate and justify moral objections more specifically directed at the genetic engineering of animals.  相似文献   
197.
    
ABSTRACT: Demand side management is being used increasingly by Ontario municipalities as a way to improve the efficiency of water use, defer the costs associated with constructing new water treatment works, and minimize the environmental impacts associated with supplying water. A comprehensive survey of 153 Ontario municipalities was completed in mid‐1998. These ranged in size from small rural townships (with populations as low as 500 people) to the province's largest urban center, Metropolitan Toronto, with a population of approximately 2.5 million people. The questionnaire measured the use of six broad types of demand side measures, including water pricing and metering; municipal by‐laws (ordinances) that promote water conservation; operational and maintenance measures to reduce water losses and consumption; water‐saving plumbing fixtures and devices; public participation programs that encourage water conservation; and other measures, such as water audits. Additionally, the survey collected data on implementation barriers and opportunities. Since the last comprehensive Ontario survey, conducted in 1987 by Kreutzwiser and Fea‐gan (1989), there has been an increase in the use of basic tools such as metering and pricing, plumbing fixtures, and public participation programs. Additionally, new initiatives, such as water audits and computerized monitoring equipment, are being used. However, in many areas opportunities exist to make better use of demand side measures. Unfortunately, municipal capacity to do so often is constrained by (among other factors) limited finances, lack of political will, and public resistance. Demonstration of real cost savings to consumers, and the development of specific goals and objectives for demand side management programs, are two important steps needed to overcome these challenges.  相似文献   
198.
The majority of disposable cups are made from paper plastic laminates (PPL) which consist of high quality cellulose fibre with a thin internal polyethylene coating. There are limited recycling options for PPLs and this has contributed to disposable cups becoming a high profile, problematic waste. In this work disposable cups have been shredded to form PPL flakes and these have been used to reinforce polypropylene to form novel paper plastic composites (PPCs). The PPL flakes and polypropylene were mixed, extruded, pelletised and injection moulded at low temperatures to prevent degradation of the cellulose fibres. The level of PPL flake addition and the use of a maleated polyolefin coupling agent to enhance interfacial adhesion have been investigated. Samples have been characterised using tensile testing, dynamic mechanical analysis (DMA) and thermogravimetric analysis. Use of a coupling agent allows composites containing 40 wt.% of PPL flakes to increase tensile strength of PP by 50% to 30 MPa. The Young modulus also increases from 1 to 2.5 GPa and the work to fracture increases by a factor of 5. The work demonstrates that PPL disposable cups have potential to be beneficially reused as reinforcement in novel polypropylene composites.  相似文献   
199.
In this study, a tracer bacteria was used to investigate the resuspension and persistence of sediment-associated bacteria in a small alluvial stream. The study was conducted in Swan Creek, located within the Grand River watershed of Ontario, Canada. A 1.1-m2 section of the bed was seeded with a strain of Escherichia coli resistant to nalidixic acid (E. coli NAR). The survival, transport, and redistribution of the tracer bacteria within a 1.7-km river section downstream of the source cell was assessed for a 2-mo period following the introduction of the tracer bacteria. This study has illustrated that enteric bacteria can survive in bed sediments for up 6 wk and that inactivation of the tracer bacteria resembled typical first-order decay. Critical conditions for resuspension, as well as resuspension rates, of sediment-associated bacteria were determined for several storm events. The critical shear stress for E. coli NAR resuspension in Swan Creek ranged from 1.5 to 1.7 N m(-2), which is comparable with literature values for critical shear stresses for erosion of cohesive sediments. Bacteria resuspension was primarily limited to the rising limb of storm hydrographs implying that a finite supply of sediment-associated bacteria are available for resuspension during individual storm events. The information presented in this paper will further the development of representative microbial water quality models.  相似文献   
200.
Regulatory frameworks to ensure municipal drinking water safety exist in most North American jurisdictions. However, similar protection is rarely provided to people reliant on water provided from private wells. In Canada, approximately 4 million people depend on privately owned, domestic wells for their drinking water. Numerous studies have shown that people who rely on private wells for their water supplies are at risk from nitrate and bacterial contamination. Given the fact that regulations relating to private wells tend to be weak or poorly enforced, actions taken by well owners to protect their own drinking water safety are extremely important. Drawing on one of the largest and most comprehensive surveys of private well owners ever conducted in Canada or elsewhere, this paper explores factors that influence well owner stewardship behaviour. Key behaviours examined included annual testing of well water and inspection of wells, measures to protect water quality, and proper decommissioning of unused wells. A geographically-stratified survey, sent to 4950 well owners in Ontario, Canada, resulted in an effective response rate of 34% (n = 1567). Logistic regression analyses revealed that motivations for well stewardship behaviours included reassurance, the perception of problems, and knowledge of the environment. Knowing how to perform stewardship behaviours was an important antecedent to action. Barriers to stewardship included complacency, inconvenience, ignorance, cost, and privacy concerns. To promote stewardship, local initiatives, better educational materials, and enforcement through real estate laws are all required. Ultimately, drinking water safety for people reliant on private wells is shown to be a responsibility shared by governments and private well owners.  相似文献   
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