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851.
Chatterjee M Silva Filho EV Sarkar SK Sella SM Bhattacharya A Satpathy KK Prasad MV Chakraborty S Bhattacharya BD 《Environment international》2007,33(3):346-356
The paper presents the first document regarding concentration, distribution and possible sources of selected trace elements (Cu, Fe, Mn, Zn, Cr, Co, Ni, Pb, Al, B and Ba) in core sediments (<63 micro particle size) from the lower stretch of Hugli (Ganges) estuary, northeast coast of Bay of Bengal by ICP-AES and EDXRF to evaluate geochemical processes influencing their distribution and possible environmental consequences. The levels of elements showed a wide range of variations in different core depths, in upper and lower intertidal zones as well as among three sampling stations. The most interesting feature of the study is the downward increase of concentrations of majority of the elements reaching overall maximum values at a depth of 20-28 cm in upper littoral zone of the site located in the extreme downstream stretch of the estuary. Values of organic carbon showed very strong positive correlations with most of the elements as revealed by correlation matrix (r) values. The interelemental relationship revealed the identical behavior of element during its transport in the estuarine environment. The overall variation in concentration can be attributed to differential discharge of untreated effluents originating from industrial, agricultural, and aquacultural sources as well as from domestic sewage along with the fishing and boating activities. The resulting compositional dataset was tested by principal component analyses and cluster analyses. Pollution load index (PLI) and index of Geoaccumulation (Igeo) revealed overall low values but the enrichment factors (EFs) for Pb were typically high for all the stations. The mean concentrations of Zn and to some extent Cu exceeded the Effects Range-Low (ER-L) values in the majority of the cases indicating that there may be some ecotoxicological risk to organisms living in sediments. The concentration of the trace elements reported in this work is useful as baselines for comparison in future sediment quality studies. 相似文献
852.
Decolorization of Remazol Black-B using a thermotolerant yeast, Kluyveromyces marxianus IMB3 总被引:4,自引:0,他引:4
Meehan C Banat IM McMullan G Nigam P Smyth F Marchant R 《Environment international》2000,26(1-2):75-79
The ability of Kluyveromyces marxianus IMB3 to decolorize Remazol Black-B dye was investigated. The effect of environmental conditions, such as pH and temperature were examined. No noticeable effects on decolorization were observed when pH varied from 3.0-5.5. Maximum colour removal, 98%, was achieved at 37 degrees C. Little or no colour removal was detected when K. marxianus IMB3 was incubated under anaerobic conditions. Further investigation, in which decolorization was monitored under extreme temperatures and low pH (to inhibit growth) and using ten fold dense inoculum, revealed that decolorization was due to biosorption to the yeast cells and not due to a metabolic reaction. 相似文献
853.
854.
Methods for integrated assessment 总被引:4,自引:1,他引:4
Integrated assessment is an approach that seeks to involve all disciplines in policy-relevant assessment. The process aims
to encompass environmental science, technology and policy problems. The aim is to establish an overview of the environmental
issue in question that attempts to avoid the mistakes of the past associated with narrow, one-sided or unidimensional approaches.
A number of methods are available for such assessments. However, they are also subject to a number of limitations, difficulties
and dilemmas. Integrated methods are inherently complicated and the tradition is that only experts are involved. New more
inclusionary procedures have to be devised in order to involve all stakeholders. They have to be involved in the framing of
the issue and in the value judgements associated with the approach. The dilemmas cannot be solved by integrated approaches,
but they can be mitigated via proper identification, analysis and evaluation of the gains and losses involved. In structuring
the analysis the existence of ignorance has to be accounted for and communicated to the managers and the political decision
makers. The ignorance/uncertainty aspects can be partially accommodated for via an intensification of feasible monitoring
and research so as to minimise the risks of unpleasant surprises.
Electronic Publication 相似文献
855.
Management of an Agroecosystem 总被引:4,自引:0,他引:4
Agroecosystems (AESs) are autotrophic ecosystems managed by man. The goal of the management is to obtain the maximum possible amount of high-quality agricultural products while preserving agricultural resources, primarily the soils and biodiversity. The main components of the management of AES structures and functions, including primary and secondary biological production, the ratio between the energy flows in the plant–man and plant–livestock–man food chains, the efficiency of energy transfer in the plant–livestock link, and conservation of agricultural resources, are considered. 相似文献
856.
857.
The ecosystem services (ES) concept is being increasingly incorporated into environmental policy formulation and management approaches. The Corporate Ecosystem Services Review (ESR) is a framework used to assess the dependence and impact that a business has on ES. The success of the corporate experience of ES assessment provides an opportunity for adaption for local authority decision making. In this paper, the ESR tool was adapted to the South African setting at a local government level, and tested at two sites in the Msunduzi Municipality, KwaZulu-Natal. In testing the tool and gathering feedback from key stakeholders, it was found that there are both opportunities and challenges to this approach. Overall, however, it provides an opportunity for the systematic inclusion of ES assessment into existing regulatory frameworks for land-use planning and Integrated Environmental Management, whether in a strategic application, at a broader spatial (municipal) scale or in a specific locale within the municipality. 相似文献
858.
Recreational Diving Impacts on Coral Reefs and the Adoption of Environmentally Responsible Practices within the SCUBA Diving Industry 总被引:1,自引:0,他引:1
859.
860.
Overview of Environmental Hazards and Health Effects of Pollution in Developing Countries: A Case Study of Nigeria 下载免费PDF全文
Pollution has taken on a global dimension, and the effects are most obvious in developing countries. The effects take a toll on human health, animals, and vegetation, as well as on soil, air, and water quality. The objective of this article is to discuss the current relationships among pollution, environmental quality, and human health within the frame of anthropogenic activities in developing countries. In addition to personal observations, we review relevant literature on conditions throughout the developing world and case studies on conditions and activities in Nigeria. Key findings show the significant, adverse contributions to human health and environmental risk from current waste generation and handling practices, indoor and outdoor air pollution, wastewater and effluent generation and disposal, the hazardous nature and pollution potential of wastes, and the human behaviors that contribute to pollution in developing countries. There is an urgent need to create awareness among the various segments of society of the human health hazards posed by pollution as well as a need for the comprehensive development and enforcement of appropriate policies to prevent a descent into an abyss of deteriorating human and environmental health. 相似文献