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1.
中国地表权、地下权概念、应用模式及相关问题分析   总被引:2,自引:0,他引:2  
文章通过对地表权、地下权相关法律概念的梳理,指出地表权、地下权概念界定的复杂性,借鉴《商业词典》对地表权和地下权的定义,探讨了在中国矿产资源一元所有制及土地二元所有制并存的情形下,地表权与地下权的应用模式、相关产权界定及存在的问题。文章分三种情形对二者的应用模式进行了探讨,指出:地表权与地下权相分离的模式是符合中国国情的一种合理选择,但是在具体实践中却存在农村集体作为土地拥有者的地位没有得到应有的尊重、矿业权主体行政审批问题严重、矿产资源的国家所有权权益没有得到应有的体现、矿产资源开发中的环境产权界定不清晰等问题;在探讨中指出两个启迪性的思路:一是使农村集体参与矿产资源开发收益分成模式;二是在现有的征地制度下,理顺价格机制,建立有效的土地流转市场,在土地使用权转让中,给予土地所有者以价格补偿。文章进一步对矿产资源开发中的土地所有权界定、税费问题、土地价格补偿及环境产权分配给予相应的分析并给出建议。  相似文献   

2.
The unhatched eggs of the following seabirds were analyzed to quantify PCBs, hexachlorobenzene (HCB), α-, β-, γ-, δ-hexachlorocyclohexanes (HCHs), o,p' and p,p' isomers of DDT, DDD and DDE: resident Adèlie (Pygoscelis adèliae, ADPE) and Emperor (Aptenodytes forsteri, EMPE) penguins, migrating snow petrel (Pagodroma nivea, SNPT) and South Polar skua (Catharacta maccormicki, SPSK) from the Ross Sea (East Antarctica); and migrating Brown skua (Catharacta antartica, BRSK) and resident ADPE from the Brainsfield Strait (West Antarctica). The general aims were to evaluate the contaminant accumulation in eggs of migrating and resident species in the two study areas, and to compare levels in penguins and skuas nesting in East and West Antarctica. PCB congener and HCH and DDT isomer profiles were also assessed. Comparisons were evaluated using seven PCB congeners (IUPAC nos. 28, 52, 101, 118+149, 138, 153, and 180), p,p'-DDE, ΣDDTs, and ΣHCHs. Higher contaminant concentrations were detected in migrating seabirds (South polar skua and brown skua)>sub-Antarctic species (snow petrel)>Antarctic species (penguins) from both the sampling sites, suggesting contamination events at lower latitudes for those birds migrating northward. HCHs showed the lowest concentrations in all species (from 0.03±0.03 ng/g wet wt in SPSK to 1.81±1.23 ng/g wet wt in ADPE from West Antarctica), and PCBs were the most abundant contaminants (from 4.34±2.15 ng/g wet wt. in EMPE to 53.41±19.61 ng/g wet wt. in brown skua). Among pesticides, it is relevant the detection of p,p'-DDT in Adèlie penguin from West Antarctica and in both species of skua; the detection of this pesticide can confirm its actual use in certain malaria-endemic countries from where it is transferred through the long range transport to the polar regions. Contaminants did not show any significant temporal trend during a ten year time span, from 1994/95 to 2004/05, in organisms collected in East Antarctica and they did not indicate any latitudinal gradient along the Ross Sea coasts.  相似文献   

3.
Arsenic (As), a naturally occurring metallic element, is a dreadful health hazard to millions of people across the globe. Arsenic is present in low amount in the environment and originates from anthropogenic impact and geogenic sources. The presence of As in groundwater used for irrigation is a worldwide problem as it affects crop productivity, accumulates to different tissues and contaminates food chain. The consumption of As contaminated water or food products leads to several diseases and even death. Recently, studies have been carried out to explore the biochemical and molecular mechanisms which contribute to As toxicity, accumulation, detoxification and tolerance acquisition in plants. This information has led to the development of the biotechnological tools for developing plants with modulated As tolerance and detoxification to safeguard cellular and genetic integrity as well as to minimize food chain contamination. This review aims to provide current updates about the biochemical and molecular networks involved in As uptake by plants and the recent developments in the area of functional genomics in terms of developing As tolerant and low As accumulating plants.  相似文献   

4.
Abstract

A pot experiment was conducted to investigate the influence of citric and oxalic acids effect on Pb and Zn uptake by corn and winter wheat. The experiment was employed with citric acid (CA) applied at 3 rates (0, 1.5 and 3.0 mmol kg?1 soil), oxalic acid (OA) at 3 rates (0, 1.5 and 3.0mmol kg?1 soil) and citric acid combined with oxalic acid (1.5 mmol citric acid combined with 1.5 mmol oxalic acid kg?1). Two types of soil were chose in the experiment. One was collected from the agricultural soil near a battery-recycling factory in Anhui province, China (site A) and the other was collected from a Pb-Zn mine residues in Hunan province, China (site B). The results showed that soil pH varied with the different treatment of citric and oxalic acids. However, there were no differences in all the treatments. 3.0mmol CA kg?1 soil addition significantly increased the concentrations of the CaCl2-extractable Pb and Zn and other treatments have no significantly increased. The highest shoot concentrations of Pb and Zn in both species occurred in application of 3.0 mmol CA/kg?1 soil and shoot concentrations of Pb and Zn in both species were significantly higher than the controls in this treatment. Shoot yields declined with application of citric and oxalic acids, indicating that the plants were sensitive to the toxicity of the metals or the amendments. The highest Pb uptake values by maize and wheat werell2.3 and 77.2 μg pot1 in soil of site A, and occurred with the control and 3.0 mmol CA/kg?1 soil respectively.  相似文献   

5.
A pot experiment was conducted to investigate the influence of citric and oxalic acids effect on Pb and Zn uptake by corn and winter wheat. The experiment was employed with citric acid (CA) applied at 3 rates (0, 1.5 and 3.0 mmol kg-1 soil), oxalic acid (OA) at 3 rates (0, 1.5 and 3.0mmol kg-1 soil) and citric acid combined with oxalic acid (1.5 mmol citric acid combined with 1.5 mmol oxalic acid kg-1). Two types of soil were chose in the experiment. One was collected from the agricultural soil near a battery-recycling factory in Anhui province, China (site A) and the other was collected from a Pb-Zn mine residues in Hunan province, China (site B). The results showed that soil pH varied with the different treatment of citric and oxalic acids. However, there were no differences in all the treatments. 3.0mmol CA kg-1 soil addition significantly increased the concentrations of the CaCI2-extractable Pb and Zn and other treatments have no significantly increased. The highest shoot concentrations of Pb and Zn  相似文献   

6.
Refrigerants used in refrigerators are an important source of ozone depleting substances released into the atmosphere, and can have a significantly negative effect on the hole in the ozone layer. But most-emission of refrigerants is man-made, unreasonable and needless. Since in most emission cases the refrigerants are contained in the refrigerators, we can retrieve them by some technique that changes the 'manual emission' into manual retrieving. To promote the retrieval action and diminish the pollution, society can use economic, administrative and technical countermeasures, which can create a 'good-cycle' both 'harnessing pollution and earning income simultaneously', reinforce the motive of retrieving, and retrieve most proportion of refrigerants used by'all refrigerators. This 'good-cycle' method can be easily promoted, and also a valuable way to promote other forms of environmental protection. The three countermeasures have almost no social cost, even no cost at all.  相似文献   

7.
During Balkan conflicts in 1994-1995, depleted uranium (DU) ordnance was employed and was left in the battlefield. Health concern is related to the risk arising from contamination of the environment with DU penetrators and dust. In order to evaluate the impact of DU on the environment and population in Bosnia and Herzegovina, radiological survey of DU in biological and water samples were carried out over the period 12-24 October 2002. The uranium isotopic concentrations in biological samples collected in Bosnia and Herzegovina, mainly lichens, mosses and barks, were found to be in the range of 0.27-35.7 Bq kg(-1) for (238)U, 0.24-16.8 Bq kg(-1) for (234)U, and 0.02-1.11 Bq kg(-1) for (235)U, showing uranium levels to be higher than in the samples collected at the control site. Moreover, the (236)U in some of the samples was detectable. The isotopic ratios of (234)U/(238)U showed DU to be detectable in many biological samples at most sites examined, but in very low levels. The presence of DU in the biological samples was as a result of DU contamination in air. The uranium concentrations in water samples collected in Bosnia and Herzegovina were found to be in the range of 0.27-16.2 m Bq l(-1) for (238)U, 0.41-15.6 m Bq l(-1) for (234)U and 0.012-0.695 m Bq l(-1) for (235)U, and two water samples were observed to be DU positive; these values are much lower than those in mineral water found in central Italy and below the WHO guideline for public drinking water. From radiotoxicological point of view, at this moment there is no significant radiological risk related to these investigated sites in terms of possible DU contamination of water and/or plants.  相似文献   

8.
Abstract

Refrigerants used in refrigerators are an important source of ozone depleting substances released into the atmosphere, and can have a significantly negative effect on the hole in the ozone layer. But most emission of refrigerants is man-made, unreasonable and needless. Since in most emission cases the refrigerants are contained in the refrigerators, we can retrieve them by some technique that changes the ‘manual emission’ into manual retrieving. To promote the retrieval action and diminish the pollution, society can use economic, administrative and technical countermeasures, which can create a ‘good-cycle’ both ‘harnessing pollution and earning income simultaneously’, reinforce the motive of retrieving, and retrieve most proportion of refrigerants used by all refrigerators. This ‘good-cycle’ method can be easily promoted, and also a valuable way to promote other forms of environmental protection. The three countermeasures have almost no social cost, even no cost at all.  相似文献   

9.
节能减排不仅是推进我国国民经济又好又快发展的核心要义,也是应对全球气候变化的迫切需要.在我国,要实现到2020年单位国内生产总值的二氧化碳排放比2005年下降40%-45%的约束性目标,需要进行艰难的产业结构调整、能源消费结构调整和经济发展阶段跨越,并应采取体制、政策、技术和管理等综合推进措施.包括政府投资、税收、政府采购和财政贴息在内的财税政策措施对于推进我国节能减排至关重要.本文认为,政府投资政策应重在支持高新技术产业研发应用,经由产业结构调整促进节能减排;税收政策应立足于综合采取增设环境污染税、低技术污染税以及税收优惠和减免等激励和惩罚并重措施;政府采购应通过扩大高效节能减排产品市场需求,引导企业生产行为;财政贴息则应侧重于解决企业节能减排投资以及技术改造过程中的资金约束.  相似文献   

10.
《Environment international》2012,38(8):1329-1335
The unhatched eggs of the following seabirds were analyzed to quantify PCBs, hexachlorobenzene (HCB), α-, β-, γ-, δ-hexachlorocyclohexanes (HCHs), o,p′ and p,p′ isomers of DDT, DDD and DDE: resident Adèlie (Pygoscelis adèliae, ADPE) and Emperor (Aptenodytes forsteri, EMPE) penguins, migrating snow petrel (Pagodroma nivea, SNPT) and South Polar skua (Catharacta maccormicki, SPSK) from the Ross Sea (East Antarctica); and migrating Brown skua (Catharacta antartica, BRSK) and resident ADPE from the Brainsfield Strait (West Antarctica). The general aims were to evaluate the contaminant accumulation in eggs of migrating and resident species in the two study areas, and to compare levels in penguins and skuas nesting in East and West Antarctica. PCB congener and HCH and DDT isomer profiles were also assessed. Comparisons were evaluated using seven PCB congeners (IUPAC nos. 28, 52, 101, 118 + 149, 138, 153, and 180), p,p′-DDE, ΣDDTs, and ΣHCHs. Higher contaminant concentrations were detected in migrating seabirds (South polar skua and brown skua) > sub-Antarctic species (snow petrel) > Antarctic species (penguins) from both the sampling sites, suggesting contamination events at lower latitudes for those birds migrating northward. HCHs showed the lowest concentrations in all species (from 0.03 ± 0.03 ng/g wet wt in SPSK to 1.81 ± 1.23 ng/g wet wt in ADPE from West Antarctica), and PCBs were the most abundant contaminants (from 4.34 ± 2.15 ng/g wet wt. in EMPE to 53.41 ± 19.61 ng/g wet wt. in brown skua). Among pesticides, it is relevant the detection of p,p′-DDT in Adèlie penguin from West Antarctica and in both species of skua; the detection of this pesticide can confirm its actual use in certain malaria-endemic countries from where it is transferred through the long range transport to the polar regions. Contaminants did not show any significant temporal trend during a ten year time span, from 1994/95 to 2004/05, in organisms collected in East Antarctica and they did not indicate any latitudinal gradient along the Ross Sea coasts.  相似文献   

11.
Fate and transport of pathogens in lakes and reservoirs   总被引:3,自引:0,他引:3  
Outbreaks of water-borne disease via public water supplies continue to be reported in developed countries even though there is increased awareness of, and treatment for, pathogen contamination. Pathogen episodes in lakes and reservoirs are often associated with rain events, and the riverine inflow is considered to be major source of pathogens. Consequently, the behaviour of these inflows is of particular importance in determining pathogen transport and distribution. Inflows are controlled by their density relative to that of the lake, such that warm inflows will flow over the surface of the lake as a buoyant surface flow and cold, dense inflows will sink beneath the lake water where they will flow along the bathymetry towards the deepest point. The fate of pathogens is determined by loss processes including settling and inactivation by temperature, UV and grazing. The general trend is for the insertion timescale to be shortest, followed by sedimentation losses and temperature inactivity. The fate of Cryptosporidium due to UV light inactivation can occur at opposite ends of the scale, depending on the location of the oocysts in the water column and the extinction coefficient for UV light. For this reason, the extinction coefficient for UV light appears to be a vitally important parameter for determining the risk of Cryptosporidium contamination. For risk assessment of pathogens in supply reservoirs, it is important to understand the role of hydrodynamics in determining the timescale of transport to the off-take relative to the timescale of inactivation. The characteristics of the riverine intrusion must also be considered when designing a sampling program for pathogens. A risk management framework is presented that accounts for pathogen fate and transport for reservoirs.  相似文献   

12.
Based on the results of our own long-term experiments and the analysis of published data, the process of individual development (ontogeny) of trees and the parameters of ontogenetic stages are described. Changes in the environment-forming (edificatory) role of a tree in the course of ontogeny and upon its completion are characterized. The performance of this role leads to the formation of the following components of biogeocenosis heterogeneity: phytogenic fields of trees, gaps in the tree canopy, and windfall–soil complexes. The data concerning the interrelation of structural transformations of the plant and soil covers in the course of forest vegetation and soil formation on the primary substrate are reviewed.  相似文献   

13.
Sub-Saharan Africa has been portrayed as the most vulnerable region to the impacts of global climate change because of its reliance on agriculture which is highly sensitive to weather and climate variables such as temperature, precipitation, and light and extreme events and low capacity for adaptation. This article reviews evidence on the scope and nature of the climate change challenge; and assesses the impact of climate change on agriculture and food security in Sub-Saharan Africa. From the review, it is apparent that the climate in Africa is already exhibiting significant changes, evident by changes in average temperature, change in amount of rainfall and patterns and the prevalence of frequency and intensity of weather extremes. The review also revealed that although uncertainties exist with regards to the magnitude of impacts, climate will negatively affect agricultural production in Sub-Saharan Africa. Specifically, as result of current and expected climate change, the area suitable for agriculture, the length of growing seasons and yield potential, particularly along the margins of semi-arid and arid areas, are expected to decrease. These impacts will affect all components of food security: food availability, food accessibility, food utilisation and food stability and hence increase the risk of hunger in the region. The review thus confirms the general consensus that Sub-Saharan Africa is the most vulnerable region to climate change. It suggests that, policymakers and development agencies should focus on formulating and implementing policies and programmes that promote farm level adaptation strategies currently being practiced by farmers across the region.  相似文献   

14.
Bangladesh and India are among the world’s most populous but also most vulnerable countries to environmental risks. In addition to storms, sea-level rise, floods and droughts, local communities face a multitude of pre-existing and concomitant economic and socio-political risks. To understand these risks and how communities respond to them is critical in securing community livelihoods. We therefore ask what are the livelihood risks; how do they impact the human security of environment sensitive communities in Satkhira, Bangladesh and in Odisha, India; and, what are the responses of these communities to the livelihood risks? The communities studied in Bangladesh depend mainly on the shrimp and fish resources of the Sundarbans mangrove forest. The two communities researched at Lake Chilika in India depend on fishing and salt farming, respectively. The field research, conducted in 2012 and 2013, shows that the communities face multiple and interacting livelihood risks. While storms and floods are common environmental risks in both countries, related livelihood risks are case-specific. In Bangladesh, attacks by criminals are the major threat to human well-being, while in India, it is violent conflict between lake users. Unsustainable resource extraction is found in both study countries. In Bangladesh, shrimp farming weakens the flood protection, while in India, illegal prawn farming marginalizes poorer lake users. Accessing loans and labor migration are responses observed in both countries. We conclude that adaptation to environmental changes needs to be sensitive to the interaction between governance, local institutions and socio-economic developments.  相似文献   

15.
The chemical composition and microbiological contamination of well water and Nile River water used for drinking were investigated in localities around Khartoum, Sudan, to present baseline data. The chemical analyses results obtained indicated that public health hazards due to pH, Ca++, CO3??, HCO3?, and NO3? are unlikely in all the samples studied, while Na+ and Cl? ions concentrations in well water warrant some attention. Contamination from organic matter and suspended material is also negligible. Microbial contamination with coliform and fecal coliform is high in surface wells and in the Nile River, but negligible in deep bores, tap water, and mineral water. The logarithm of the colony count ranges from zero for mineral water to 6.8 for water from the White Nile. In addition to drawing further attention to the well water and Nile water used for drinking by a wide sector of the population, the microbial count data for water from the Nile disagreed with the generally held belief that the Nile, being one of the largest rivers of the world, carries no detectable fecal contamination. Our data also did not support the belief that the White Nile is more contaminated than the Blue Nile.  相似文献   

16.
环境载荷与环境压强:环境压力指标及应用   总被引:2,自引:0,他引:2  
一个国家的经济活动产生的环境压力与其具有的环境承载能力。决定了该国社会与经济发展的可持续状况。因此.测度环境压力和承载力是制定可持续发展目标和政策的必要条件之一。基于国家尺度的社会代谢物质流、地理面积和生态承载面积。可以构建出一个国家本国环境所承受的环境压力总量指标体系——环境载荷和环境压强;德国、荷兰、奥地利、日本和美国等五个工业国家的环境载荷和各环境压强总量指标若干年的实证计算和对比分析。可以发现.虽然美国的国内环境总载荷、人均物质总需求及人均生态足迹赤字等均是各国最高者.其环境压强却处于五国的最低端。与奥地利相近;以环境压强指标测度。除日本不明显外.其余四国的经济发展与本国环境压力之间在研究期(1975—1996)均显示出“脱钩”关系.即本国环境压强并没有随经济总量的增长而增加。为此.最后就环境问题的公平性和环境压力指标的优缺点进行简要讨论。  相似文献   

17.
In order to contribute to a future waste management policy related to the presence of technologically enhanced natural occurring radioactive material (TENORM) in the Brazilian petroleum industry, the present work presents the chemical composition and the 226Ra and 228Ra content of sludge and scales generated during the offshore E and P petroleum activities in the Campos Basin, the primary offshore oil production region in Brazil.The 226Ra and 228Ra content on 36 sludge and scales samples were determined by gamma-spectrometry. Based on X-ray diffractometry results, a chemical analysis schema for these samples was developed. The results have shown that scales are 75% barium and strontium sulfates, with a mean 226Ra and 228Ra content of 106 kBq kg−1 and 78 kBq kg−1, respectively. On the other hand, sludge samples have a much more complex chemical composition than the scales. The 226Ra and 228Ra content in sludge also varies much more than the content observed in the scales samples and ranged from 0.36 to 367 kBq kg−1 and 0.25 to 343 kBq kg−1, respectively.  相似文献   

18.
Uptake of uranium and thorium by native and cultivated plants   总被引:2,自引:0,他引:2  
Large part of available literature on biogeochemistry of uranium and thorium refers to the studies performed either in highly contaminated areas or in nutrient solutions that have been artificially ‘spiked’ with radionuclides. Effects of background levels of natural radioactivity on soil-grown plants have not been studied to the same extent. In this paper, we summarised results of greenhouse and field experiments performed by the author from 2000 to 2006. We examined some of the factors affecting transfer of U and Th from soil to plants, differences in uptake of these radionuclides by different plants, relationships between U and Th in soil and in plants, and temporal variations of U and Th in different plant species. Concentrations of radionuclides (critical point for experimental studies on biogeochemistry of U and Th - rare trace elements in non-contaminated regions) and essential plant nutrients and trace elements were determined by instrumental neutron activation analysis.  相似文献   

19.
The political decision concerning modernization of Russian economy is impossible to implement without ecomodernization. The development of more efficient industrial, transportation, and agricultural technologies should be coordinated with measures to support natural self-regulation in ecosystems. Consideration is given to errors and misjudgments made in the course of modernization and possible measures to optimize and scientifically support this process in the interests of advancement in hunting and game management.  相似文献   

20.
The widespread use of brominated flame-retarded products in the last two decades has resulted in an increasing presence of bromine in thermal processes such as waste combustion and accidental fires. Brominated and brominated-chlorinated dibenzodioxins and dibenzofurans (PBDDs/PBDFs, PXDDs/PXDFs) are micropollutants of concern arising from such processes. The present review aims to evaluate the relevance of these compound classes in actual thermal processes. Four categories of thermal processes are discussed in this respect according to their potential for PBDD/PBDF and PXDD/PXDF generation: thermal stress, pyrolysis/gasification, insufficient combustion conditions and controlled combustion conditions. Under thermal stress situations, as they may occur in production or recycling processes, PBDDs/PBDFs precursors like polybrominated diphenylethers (PBDE) can have a relevant potential for PBDD/PBDF formation via a simple elimination. Under insufficient combustion conditions as they are present in, e.g. accidental fires and uncontrolled burning as well as gasification/pyrolysis processes, considerable amounts of PBDDs/PBDFs can be formed from BFRs, preferably via the precursor pathway. In contrast, under controlled combustion conditions, BFRs and PBDDs/PBDFs can be destroyed with high efficiency. The relevance of de novo synthesis of PXDDs/PXDFs is discussed for this condition.Providing a basis for the understanding of PXDD/PXDF formation in actual thermal processes, the present paper also summarises the formation pathways of brominated and brominated-chlorinated PXDDs/PXDFs from brominated flame retardants (BFRs) investigated during laboratory thermolysis experiments. Relevant mechanistic steps for PBDD/PBDF formation from brominated precursors are discussed including elimination reactions, condensation steps and debromination/hydrogenation reactions.In addition, chlorination/bromination and halogen exchange reactions are briefly discussed with respect for their relevance on the final distribution of PBDDs/PBDFs, mixed chlorinated PXDDs/PXDFs and PCDDs/PCDFs resulting from thermal processes.  相似文献   

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