武汉城市圈水资源及水环境承载力分析

水资源及水环境承载力是衡量区域可持续发展的一项重要指标,对区域经济的发展规划具有重要的指导意义。以可承载的人口数量和GDP作为承载力的表征指标,分别运用单位GDP综合用水量评判法和河流一维水质模型及湖库均匀混合模型计算武汉城市圈不同水平年的水资源及水环境承载力,并用承载度来评价水资源及水环境的承载状态。结果表明:2012、2020和2030年武汉城市圈水资源承载力都处于合理承载状态,但是其水环境承载力处于轻度超载状态。可见,水环境承载力对武汉城市圈的用水限制更为严格。随着社会经济的发展及污水处理技术的进步,水环境状况虽然会有所好转,但与水资源数量这一因素相比,水环境仍是制约武汉城市圈经济社会发展的关键因素。     

基于RS-SVR模型的流域水资源脆弱性评价与预测研究——以黄河流域为例

水资源脆弱性是衡量水资源系统在气候变化以及人类活动影响下的流域承载能力的重要标准,流域水资源脆弱性评价与预测是评估流域水安全状况、辨识未来水资源系统存在的问题的重要手段。该文首先构建了黄河流域水资源脆弱性评价指标体系,利用粗糙集(Rough Set,缩写为RS)方法对原始指标体系进行降维去除冗余属性。然后,将降维后的评价指标标准值作为"评价样本",运用支持向量机回归(Support Vector Regression,缩写为SVR)模型对流域水资源脆弱性进行评价。最后,设定未来3种不同气候模式与社会经济情景,对黄河流域水资源脆弱性进行情景预测。结果表明:黄河流域过去16年间整体水资源脆弱性等级已从Ⅴ级提升到Ⅳ级水平,未来情景1、情景2下流域整体水资源脆弱性将会好转,但仍处于Ⅳ级中度脆弱水平。未来水质脆弱性与灾害脆弱性提升较为明显,水量脆弱性没有显著改善,在情景3下将恶化到Ⅴ级中高脆弱。因此未来采取积极的人工调控措施能使得水质与灾害方面获得明显的提升,而水量脆弱性则成为制约未来流域整体水资源脆弱性的瓶颈。     

昆明市水资源承载力系统动力学模拟

针对昆明市水资源短缺的现状和水资源系统所具有的复杂系统特征,在综合考虑水资源需求、水资源供给、污水再生利用、外地供水、缺水程度的影响等因素的情况下,利用系统动力学(SD)方法建立了昆明市水资源承载力SD模型,在现状延续型、经济发展型、资源节约型、环境友好型和协调发展型5种方案下模拟2015～2030年昆明市水资源承载能力的动态变化,寻求提高昆明市水资源承载力的途径。结果表明:现状延续型用水模式出现十分严重的水资源匮乏问题,水资源承载能力很容易达到极限承载值,不能实现昆明市资源环境与社会经济的可持续发展;经济发展型模式虽然提高了经济水平,但是加剧了生态环境污染和缺水问题,供需比低至0.25;采用资源节约型或环境友好型模式,虽然可以适当缓解生态环境污染及缺水问题,但是随着时间的推移,缺水现象依然严峻;而在建设资源节约型或环境友好型社会的前提下,适当减缓城市发展规模增速,实施水资源集约利用、污水处理再生和加强外地供水的协调发展型方案可以实现昆明市水资源的供需平衡,资源环境与社会经济可持续发展,为5种方案中的最优方案。     

土地城市化背景下武汉市资源环境承载力仿真研究

运用Vensim软件,通过构建"土地城市化-资源环境承载力"系统动力学模型对不同情景下武汉市资源环境承载力的发展趋势进行仿真,为土地城市化背景下武汉市未来发展方向提供参考。结果显示,协调发展型是最适合武汉市的发展模式,而现状延续型、政绩驱动型和生态环保型情景下武汉市资源环境承载力到2020年均将面临超载压力。武汉市在适当加速推进土地城市化的同时应注重增加耕地面积、加强基础设施建设、降低资源消耗和污染排放,确保资源环境承载系统平稳运行。     

浙江省水土保持措施对水资源的影响

浙江省作为我国东部经济发达地区,在经济不断向前发展的同时,更应该保证水资源这一重要经济发展基本条件的安全性。洪涝灾害、水资源短缺和水污染问题是我国三大主要水问题。水土保持措施具有水量效应和水质效应,是解决水问题之根本性、战略性措施。水土保持措施改变了流域产流、汇流下垫面的条件,从而改变流域水文过程。同时,水土保持措施还可以吸收、过滤、迁移和转化土壤或水体中的部分有害物质,具有防治流域、区域非点源污染,改善地表、地下水水质的作用。     

跨国水资源保护的法律措施——兼及中国的实践

国际流域各国在自己境内利用跨国水资源或进行其他活动时,有义务保护国际流域水资源,防止对其他流域国造成重大损害。对有关国际文件的规定和国际社会的实践进行了系统的分析和比较,从促进跨国水资源包括涉及我国的跨国水资源保护的目的出发,运用比较、概括和归纳的方法,对流域各国保护国际流域水资源的法律措施进行了归纳和总结。这些措施包括但不限于环境影响评价、交流信息、监测、通知、紧急情况下的援助、控制污染、公众参与等。最后就中国促进相关跨国水资源的保护提出了具体的措施建议：严格执行《环境影响评价法》、《水污染防治法》等法律法规;建立跨国河流水环境监测网;保持和加强与相邻国家和沿岸各国的信息交流与合作;继续与更多的沿岸国谈判和签署双边或多边流域保护协议,并建立流域保护或管理委员会负责对跨国河流流域的保护与管理.     

流域内经济结构性调整对水环境质量的长短期效应分析

随着流域内工业化和城镇化的深入发展,流域水环境面临的形势十分严峻,太湖流域作为我国社会经济发展最快的地区之一,其水体质量不容乐观。为了实现流域内经济、社会和环境的协调发展,本文首先基于主成份分析法确定太湖流域水质综合污染指数,以此表征流域水环境质量。在此基础上,基于ARDL模型的边限协整检验方法,利用1991—2014年的太湖流域(江苏部分)产业结构调整、人口城乡流动和政府环境规制的相关数据,从经济结构性调整视角分析其对流域水环境质量的长短期效应。实证结果表明:产业结构调整对水环境质量的长短期弹性分别为79.522和-179.283,说明流域内第二产业的长期粗放式增长会导致水质恶化,而且其影响程度并不会随着时间而自动消退。而人口城乡结构变化对水环境质量的长短期弹性分别为67.578和309.411,说明流域内人口从农村流动到城市,短期会增加用水量,加剧水质恶化,而长期造成的负面影响则会相对逐渐减弱。至于政府在流域治理方面的规制行为,由于其长短期弹性分别为-21.705和19.687,说明政府治理行为短期并不会有效改善水体质量,其管制效果并非立竿见影,往往需要等待若干年才能有初步成效,而且相比产业结构和人口城乡结构对流域水环境质量的影响程度,政府环境规制对水质的影响力度略显不足。最后基于实证分析结果,本文提出了促进改善流域水环境质量的若干政策建议,包括:优化第一产业和大力发展第三产业,促进产业结构优化调整;加大城市环境保护宣传力度,普及节水意识和管制排污行为,并扶植农业发展,实现城乡人口数量的合理流动;促进研发一些高新排污设备,继续加大政府在治理污水方面的投资,强化政府的环境规制行为等。     

大江大河流域水资源管理问题讨论

世界范围内水危机的日益严重,越来越显现出流域水资源管理的重要性。从分析国内外大江大河水资源研究的热点入手,介绍了国内江河流域水资源管理思路的转变和实践;系统分析了大流域水资源存在问题的根本原因,认为是由于对人水关系和流域生态演化规律,河流、湿地的生态功能、流域的整体性管理重视不够造成的。从河流的生态整体性出发,以生态学为理论基础,提出了考虑社会—经济—环境复合生态系统,以生态和谐行为、协调发展、因地制宜、流域整体性调控体制和生态文化建设等维持大流域水资源可持续利用和保护的生态可持续性的保障措施。     

农村水环境保护与经济可持续发展

我国的生态环境问题 ,如水土流失、草场退化、沙漠化、盐渍化等问题 ,归根到底还是农村水环境问题。本文分析了农村水环境保护、高效利用水资源的紧迫性 ,以及影响农村生态系统可持续性的因素和保护、改善农村水环境的主要措施 ;认为加强农村水环境保护及其持续发展能力的建设是我国整个社会特别是农村经济可持续发展的基本保障     

贵阳市环境经济系统协调发展策略分析

环境与经济的协调发展已成为未来城市发展的必然要求,在西部大开发战略实施的当前形势下,如何实现贵阳市环境—经济系统协调发展是当地拟研究的一个重要问题。阐述了贵阳市环境经济系统的特征,在引入和结合系统动力学、情景分析和协调度分析三种方法的基础上,提出了贵阳市协调发展策略分析的研究框架。遵循框架中的思路和方法,构建了贵阳市环境经济系统仿真模拟模型,围绕GDP增长、资源消耗、环境污染、环保设施建设方面进行了5个情景的情景预测和协调度分析,通过反复模拟、反馈、调整及分析,识别出情景5为较理想的一种发展模式,总结提出了相应的基本策略方向。研究结果是贵阳市未来发展的科学参考和决策支持。     

Natural outdoor environments and mental and physical health: Relationships and mechanisms

BackgroundEvidence is growing for the beneficial impacts of natural outdoor environments on health. However, most of the evidence has focused on green spaces and little evidence is available on health benefits of blue spaces and about possible mediators and modifiers of such impacts. We investigated the association between natural outdoor environments (separately for green and blue spaces) and health (general and mental) and its possible mediators and modifiers.MethodsCross-sectional data from adults interviewed in Catalonia (Spain) between 2010 and 2012 as part of the Catalonia Health Survey were used. The collected data included sociodemographic characteristics, self-perceived general health, mental health, physical activity and social support. Indicators of surrounding greenness and access to natural outdoor environments within 300 m of the residence and degree of urbanization were derived for residential addresses. Associations were estimated using logistic regression and negative binominal models.ResultsGreen spaces were associated with better self-perceived general health and better mental health, independent of degree of urbanization. The associations were more consistent for surrounding greenness than for access to green spaces. The results were consistent for different buffers, and when stratifying for socioeconomic status. Slightly stronger associations were found for women and residents of non-densely populated areas. No association was found between green spaces and social contacts and physical activity. The results for blue spaces were not conclusive.ConclusionGreen spaces are associated with better general and mental health across strata of urbanization, socioeconomic status, and genders. Mechanisms other than physical activity or social support may explain these associations.     

循环经济与节能减排解析

目前我国经济增长模式是粗放的、不循环的经济增长模式,经济发展过程中存在着高增长、高能耗、高环境问题,作者通过一系列的数据对比和分析,指出当前发展循环经济,促进节能减排是我国经济发展过程中面临的第一要务。胡锦涛同志在党的十七大报告中提出一定要“落实节能减排工作责任制”,更表明了我国当前发展循环经济,促进节能减排的决心。本文首先提出循环经济与节能减排的相关概念及含义;再以重点行业中的电力、钢铁行业如何搞好能源资源节约和“三废”综合利用为例对我国发展循环经济、促进节能减排进行了实证分析;最后提出要通过加快资源价格机制的改革、促进技术创新、完善政策法规体系、转变领导片面追求GDP增长的认识等措施来达到发展循环经济、促进节能减排的目标。     

加拿大环境与可持续发展科技创新及对我国的启示

加拿大重视环境保护与可持续发展中的科技创新,在全联邦范围内营造了"政府引导、企业主体、国民支持"的良好创新氛围,形成了"以科技创新支撑环境产业发展,以环境产业促进环境保护与可持续发展"的鲜明环保特色,走出了一条科技创新、产业发展、环境保护和可持续发展三者协同发展、相互制衡、良性循环的发展路子,值得我国借鉴.在我国的环境与可持续发展科技创新中,存在着创新能力不足、产学研合作薄弱、产业化乏力等问题.本文通过中加比较,探讨了我国实施环境与可持续发展科技创新的对策思路,即政府应完善环保法规政策、健全环保标准和管理体系;应增加科研投入,建立政府调控下的市场化投资体系和环境科技的产业化发展;应选择重点领域实现优先发展,突破瓶颈产业;应重视合作创新,加强部门合作,科研机构合作以及国际合作.     

中国地表权、地下权概念、应用模式及相关问题分析

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。     

Chlorinated biphenyls and pesticides in migrating and resident seabirds from East and West Antarctica

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.     

Chlorinated biphenyls and pesticides in migrating and resident seabirds from East and West Antarctica

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.     

Harmful and Needless Emission of Refrigerant and Countermeasures

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.     

Harmful and Needless Emission of Refrigerant and Countermeasures

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.     

Citric and Oxalic Acids Effect on Pb and Zn Uptake by Maize and Winter Wheat

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.     

Omics and biotechnology of arsenic stress and detoxification in plants: Current updates and prospective

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.