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491.
Eliza Kluckow Jane Halliday Alice Poulton Anthea Lindquist Briohny Hutchinson Michael Bethune Leonard Bonacquisto Fabricio Da Silva Costa Lucy Gugasyan James Harraway Amanda Howden Abhijit Kulkarni Nicole Martin Richard McCoy Melody Menezes Debbie Nisbet Ricardo Palma-Dias Mark D. Pertile Zeffie Poulakis Lisa Hui 《黑龙江环境通报》2019,39(13):1254-1261
492.
Kanaji Masakorala Jun Yao Radhika Chandankere Haijun Liu Wenjuan Liu Minmin Cai Martin M. F. Choi 《Environmental science and pollution research international》2014,21(1):454-463
Main physicochemical and microbiological parameters of collected petroleum-contaminated soils with different degrees of contamination from DaGang oil field (southeast of Tianjin, northeast China) were comparatively analyzed in order to assess the influence of petroleum contaminants on the physicochemical and microbiological properties of soil. An integration of microcalorimetric technique with urease enzyme analysis was used with the aim to assess a general status of soil metabolism and the potential availability of nitrogen nutrient in soils stressed by petroleum-derived contaminants. The total petroleum hydrocarbon (TPH) content of contaminated soils varied from 752.3 to 29,114 mg kg?1. Although the studied physicochemical and biological parameters showed variations dependent on TPH content, the correlation matrix showed also highly significant correlation coefficients among parameters, suggesting their utility in describing a complex matrix such as soil even in the presence of a high level of contaminants. The microcalorimetric measures gave evidence of microbial adaptation under highest TPH concentration; this would help in assessing the potential of a polluted soil to promote self-degradation of oil-derived hydrocarbon under natural or assisted remediation. The results highlighted the importance of the application of combined approach in the study of those parameters driving the soil amelioration and bioremediation. 相似文献
493.
This paper reports findings from research which sought to examine the characteristics and the behaviour of farms which participate in environmentally friendly farming schemes and initiatives. In contrast with some earlier work in other regions, a wide variety of farmers in the south-west sample had an active level of sympathy or interest in conservation issues, which, despite the broad and at times inaccurate conservation definitions employed by the farmers, led some to spend generously on creative activities, especially woodland planting. However, the importance of geographical influences was paramount, with creative conservation activity almost always undertaken on comparatively poorer land. Poorer land was always most suitable for conservation work, whether that work be done for cosmetic or holistic reasons. 相似文献
494.
This paper develops and tests hypotheses concerning some psychological correlates of role ambiguity and role conflict in a population that has not been extensively studied in relation to stress, union stewards. Survey data on role ambiguity and role conflict, the indicators of stress, were collected from 285 stewards at the local union steward meeting, with the stewards perceiving a moderate amount of role ambiguity and perceiving a lesser amount of role conflict. The stewards were also asked about their role expectations, their motivations for remaining a steward, their grievance handling strategies, and their affective commitment toward the union and employer. Each of those four sets of variables was hypothesized to be related to role ambiguity and role conflict and each was influential in explaining variance. As predicted, those stewards who were more motivated to remain stewards for personal reasons had both higher role ambiguity and higher role conflict. Further, the conditions of being more motivated to remain a steward to help the union and employees and having higher union commitment were associated with lower role conflict, but, opposite to the hypotheses, higher role ambiguity. 相似文献
495.
496.
John K. Yu Martin M. Fogel 《Journal of the American Water Resources Association》1978,14(5):1239-1250
ABSTRACT: Use-oriented benefits and treatment costs analysis has been incorporated into a water quality index to show an economically optimized concentration for the treatment of the pollutants and the resulting water quality. This combined water quality index can be used in decisionmaking at the federal and local government levels. Five major pollutants, i.e., coliforms, nitrogen, phosphorus, suspended solids, and detergent, have been considered for the municipal waste water. With each higher level of improvement the treatment costs increase accordingly and the benefits associated with the reuse of this treated waste water will increase too but not for the nutrient removal in agricultural use. The optimal concentration is determined when the marginal costs equal the marginal benefits. The combined water quality index is the combination of the maximum net benefits and the water quality index of the optimized residual concentrations. This water quality index is zero dollars for the Tucson region in this study. The possible reclaimed use of municipal waste water is for agricultural irrigation and recreational lakes for the Tucson region. 相似文献
497.
498.
Martin T. Farris 《Journal of the American Water Resources Association》1971,7(6):1128-1136
While the science of economics is widely used in Federal water resource development projects, the usual procedure of applying an analytical discipline to arrive at a conclusion is reversed. The “answer” is usually provided ahead of time and economics is assigned the task of justifying the preconceived conclusion. This leads to a series of mitigatory effects in which economics as a science is not allowed to freely function. This article attempts to illustrate some of these “unusual” uses of economics in Federal water projects and note the “answers” we would logically expect from the economic discipline. Even though the theory of economics is often subverted, there are positive aspects to the role of economics in evaluating Federal water projects. 相似文献
499.
A review of approaches for classifying benthic habitats and evaluating habitat quality 总被引:4,自引:0,他引:4
We have assessed the current state of knowledge relative to methods used in assessing sub-tidal benthic habitat quality and the classification of benthic habitats. While our main focus is on marine habitat, we extensively draw on knowledge gained in freshwater systems where benthic assessment procedures are at an advanced stage of maturity. We found a broad range of sophistication/complication in terms of the methods applied in assessing and mapping benthic habitats. The simplest index or metric involved some assessment of species richness, while the most complicated required utilizing multi-variate analysis. The simplest mapping attempts equated physical substrate with benthic habitat while the most sophisticated relied on extensive environmental preference and groundtruth data for species of concern. The leading edge of methods for benthic habitat mapping involves combining the advances in optical and acoustic methods that allow for routine classifying and mapping of the seafloor with biological and habitat data for species of concern. The objective of this melding of dispirit methods is to produce benthic habitat maps with broad system wide coverage and sound biological underpinning. It is clear that the disparity in information density between the physical and biological sides of the equation currently hinder applicability and acceptability of benthic habitat mapping efforts. In addition to the lack of basic information on the biological and environmental tolerances of targeted species, the proliferation of metrics for characterizing and assessing biological conditions further clouds the usefulness of any broad scale mapping attempt. The problem of data density mismatch between physical and biological methods will likely not be solved until acoustic methods can routinely resolve the elusive biological components that make a physical substrate a habitat. 相似文献
500.
Harper M 《Journal of environmental monitoring : JEM》2004,6(10):124N-127N