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571.
The Zijin heap bioleaching plant started operation by the end of 2005; due to the proximity of the Ting River, concerns rose about the migration of acidophiles outside of the heap. In this study, 53 soil samples and 51 liquid samples were collected, and the biogeographical distribution of acidophiles was investigated using clone libraries and real-time polymerase chain reaction (PCR), the physicochemical characteristics were analysed by Inductively Coupled Plasma Optical Emission Spectrometry (ICP). The results indicated the bioleaching system had some influence on the surrounding environment. Both microbial community and physiochemical index emerged correlation with distance of sampling sites from bioleaching system, mainly limited in the zone 30?m outside bioleaching system. Correlation analysis indicated the migration of different acidophiles was influenced by different factors. Leptospirillum had higher migration capability than the other acidophiles, and such migration capability was one of the important influence factors for its distribution. Environment factors and survival ability were the key influence factors for Acidithiobacillus, Sulfobacillus and Ferroplasma to survive in the surrounding environment.  相似文献   
572.
Over the past decade, the assessment of human systems interactions with the environment has permeated all phases of environmental and public health research. We are invoking lessons learned from the broad discipline of Systems Biology research that focuses primarily on molecular and cellular networks and adapting these concepts to Systems Exposure Science which focuses on interpreting the linkage from environmental measurements and biomonitoring to the expression of biological parameters. A primary tool of systems biology is the visualization of complex genomic and proteomic data using “heat maps” which are rectangular color coded arrays indicating the intensity (or amount) of the dependent variable. Heat maps are flexible in that both the x-axis and y-axis can be arranged to explore a particular hypothesis and allow a fast overview of data with a third quantitative dimension captured as different colors. We are now adapting these tools for interpreting cumulative and aggregate environmental exposure measurements as well as the results from human biomonitoring of biological media including blood, breath and urine. This article uses existing EPA measurements of environmental and biomarker concentrations of polycyclic aromatic hydrocarbons (PAHs) to demonstrate the value of the heat map approach for hypothesis development and to link back to stochastic and mixed effects models that were originally used to assess study results.  相似文献   
573.
India's forest biodiversity management regime is analysed at the policy, legal and institutional levels, from the perspective of the triple objectives of the Convention on Biological Diversity and the principles of the Indian constitution. The forest biodiversity management regime has both structural and functional flaws that render it largely incapable of facing the challenge of increasing biodiversity degradation and deepening poverty among the Adivasis and other forest‐dependent communities. The paper argues for the reform of the forest biodiversity management regime and offers recommendations in regard to most aspects of the regime, with a view of putting the country's conservation enterprise on a course that is effective, sustainable and inclusive, rejecting the report of the High Power Committee (HPC) (also known as the Subramanian Committee), which is premised on easing corporate access to forests.  相似文献   
574.
575.
FDI的技术效应对碳排放的影响   总被引:1,自引:0,他引:1  
随着温室效应的加剧和中国对外开放程度的不断提升,外商直接投资对东道国碳排放的影响日益引起各方重视.外商直接投资对中国工业行业的碳排放的影响如何?外商直接投资通过何种技术渠道对中国的碳排放产生影响?外商直接投资的技术效应对不同行业的影响存在何种差异?都是当前亟待研究的现实问题.利用中国1999 - 2008年35个工业行业的面板数据,分别使用反映外商直接投资不同渠道的效应的指标,并对35个工业行业按照排放强度进行分类,本文实证检验了FDI的技术效应对我国工业行业碳排放的影响.全行业的研究表明,FDI的技术效应对工业行业的碳排放具有显著的正面影响;技术影响渠道方面,FDI的人员流动效应的正面影响显著强于FDI的竞争、示范效应.分行业的研究表明,FDI的技术效应对高排放行业碳排放无显著影响,但对低排放行业碳的排放具有显著的积极影晌.最后,本文建议我国继续加大吸引外资的力度,以充分发挥FDI对工业行业碳排放降低的积极作用.  相似文献   
576.
577.
The basic function of the engineered barrier system (EBS) in geological disposal is to prevent or limit the release of radionuclides into the underground environment. For this purpose, the vitrified waste is contained in an overpack to isolate it from contact with groundwater for a certain initial period of time. However, it is impossible to ensure complete containment for all time. Therefore, the eventual release of nuclides must be minimized after the overpack fails (AEC, 1984. Radioactive waste processing and disposal measures; JNC, 2000a. Project to establish the scientific and technical basis for HLW disposal in Japan – first progress report-H3. Geological Environment in Japan, JNC TN1410 2000-002; JNC, 2000b. H12: project to establish the scientific and technical basis for HLW disposal in Japan – repository design and engineering technology, JNC TN1410 2000-003.).  相似文献   
578.
The cultivation of white rot edible fungus Pleurotus florida was performed in polybags. The corn cob was employed as basal substrate while eight different additives such as urea, ammonium sulphate, gram flour, soybean meal, ground nut cake and molasses were used with corn cob. Three different levels of variable combinations with corn cob were evaluated in response to different parameters of mushroom viz., mycelial growth, spawn running, primordial initiation, fruit body yield and its biological efficiency. Each additive at different combinations showed variable impact on the different stages of mushroom life cycle. The primordial initiation was observed for the first time during 20.2–35.1 days. The biological efficiencies in every supplemented set were increased over un-supplemented control set. Increasing the level of additives, the biological efficiency was negatively affected at higher levels. The cotton seed cake was found the best supplement producing 93.75% biological efficiency while soybean meal was the second best additive producing 93.00% yield. The highest growth rate, rapid mycelia run, early primordial initiation, highest yield and biological efficiency were recorded in the combination of corn cob and cotton seed cake at 2% (98 + 2) level.  相似文献   
579.
A methodology has been developed to carry out an integrated oil spill vulnerability index, V, for coastal environments. This index takes into account the main physical, biological and socio-economical characteristics by means of three intermediate indexes. Three different integration methods (worst-case, average and survey-based) along with ESI-based vulnerability scores, VESI, proposed for the Cantabrian coast during the Prestige oil spill, have been analyzed and compared in terms of agreement between the classifications obtained with each one for this coastal area. Results of this study indicate that the use of the worst-case index, VR, leads to a conservative ranking, with a very poor discrimination which is not helpful in coastal oil spill risk management. Due to the homogeneity of this coastal stretch, the rest of the methods, VI, VM and VESI, provide similar classifications. However, VM and VI give more flexibility allowing three indexes for each coastal segment and including socio-economic aspects. Finally, the VI procedure is proposed here as the more advisable as using this index promotes the public participation that is a key element in the implementation of Integrated Coastal Zone Management (IZCM).  相似文献   
580.
Artificial neural networks (ANNs) are being used increasingly to predict and forecast water resources' variables. The feed-forward neural network modeling technique is the most widely used ANN type in water resources applications. The main purpose of the study is to investigate the abilities of an artificial neural networks' (ANNs) model to improve the accuracy of the biological oxygen demand (BOD) estimation. Many of the water quality variables (chemical oxygen demand, temperature, dissolved oxygen, water flow, chlorophyll a and nutrients, ammonia, nitrite, nitrate) that affect biological oxygen demand concentrations were collected at 11 sampling sites in the Melen River Basin during 2001-2002. To develop an ANN model for estimating BOD, the available data set was partitioned into a training set and a test set according to station. In order to reach an optimum amount of hidden layer nodes, nodes 2, 3, 5, 10 were tested. Within this range, the ANN architecture having 8 inputs and 1 hidden layer with 3 nodes gives the best choice. Comparison of results reveals that the ANN model gives reasonable estimates for the BOD prediction.  相似文献   
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