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1.
The paper presents a method to determine the most influencing stressors and the most susceptible resources for complex assessment problems involving multiple stressors impacting multiple resources over a region. The method is based on the concept of limiting priorities in a square matrix which capture the transmission of influence along all paths between stressors and resources in the matrix. The proposed method allows the relationship between stressors and resources to be looked at in both univariate and multivariate fashion, taking into account the interactions among the variables. Hypothetical and case study examples are given for illustration purpose. It shows that the proposed method is suitable for the determination of the most important stressors and the most susceptible resources, a common (but often uneasy) task in integrated environmental assessment.  相似文献   

2.
天津公园土壤重金属污染评价及其空间分析   总被引:3,自引:0,他引:3  
随着城市化和工业化进程的加快,我国城市及其周边目前已遭受到明显的重金属污染,本文着重研究了天津17个主要公园土壤重金属的污染特征。2007年10月采集公园土壤样品,利用ICP-MS分析土壤重金属的含量。研究结果表明:Cu、Zn、Ni、Cr、Cd和Pb的平均质量分数分别为36.57mg·kg-1,116.56mg·kg-1,30.15mg·kg-1,51.04mg·kg-1,0.25mg·kg-1和31.62mg·kg-1。以天津市土壤背景值为评价标准,天津公园土壤重金属污染属于中度污染和轻微生态风险。重金属主要污染因子为Cd,其次是Pb、Zn和Cu。天津中环线以内区域公园土壤重金属污染较中外环线之间相比较重。不同行政区划区域公园土壤重金属污染从综合污染指数来看,由重到轻的顺序为:红桥区〉河北区〉河东区〉南开区〉河西区〉和平区〉北辰区;从潜在生态指数评价来看,由重到轻的顺序为:红桥区〉河北区〉河东区〉南开区〉河西区〉北辰区〉和平区。  相似文献   

3.
微塑料是尺寸小于5 mm的塑料碎片或纤维,近年来在环境科学领域得到广泛关注. 污水处理厂作为它的重要汇集点和排放源,是水环境微塑料来源的重要途径. 本研究选取重庆市长江流域周围工业污水处理厂(n=6)、生活污水处理厂(n=6)和垃圾填埋场(n=6)作为研究对象,针对污水处理厂进、出水微塑料特征和对周边受纳水体产生的生态风险展开研究. 结果显示,工业和生活污水处理厂进水中的微塑料平均丰度分别为(5.26±2.69) n·L−1和(17.11±19.39) n·L−1,垃圾填埋场为(17.13±20.39) n·L−1;出水平均丰度分别为(1.43±0.62) n·L−1、(1.14±0.66) n·L−1和(2.12±1.72) n·L−1. 生活污水处理厂对微塑料的清除率最高(76.47%—98.93%,P<0.05). 各类污水处理厂进、出水微塑料特征主要以纤维和碎片状的聚对苯甲酸乙二醇酯(PET)、聚丙烯(PP)、聚乙烯(PS)和人造丝为主. 受纳水体中的微塑料平均丰度为(3.31±1.85) n·L−1,显著高于对照水体(P<0.05). 受纳水体检出微塑料种类与特征与污水处理厂相似,并且检出数量与污水处理厂排水中微塑料丰度显著相关(P<0.05). 生态风险评估显示,大多数受纳水体的采样点存在较高的生态风险. 本研究揭示了不同污水处理厂在微塑料清除率、排放特征上的差异和对周边水体的潜在生态风险,为微塑料污染管控提供了参考数据.  相似文献   

4.
桂林市菜地土壤-蔬菜汞污染研究和评价   总被引:3,自引:0,他引:3  
侯明  钱建平  张力  胡存杰 《生态环境》2004,13(4):575-577,584
对桂林市近郊8个不同片区蔬菜产地的118个土壤样品和71个蔬菜样品中汞的含量水平进行了调查和分析。运用单因子污染指数法评价了菜地土壤一蔬菜中汞的污染现状。研究表明,桂林市及近郊菜地土壤和蔬菜已受到不同程度的汞污染,全市各片区菜地土壤汞含量平均值为0.098-0.523mg/kg,以国家土壤环境质量标准二级标准评价,土壤平均污染指数在0.33-1.74范围内,属非污染或轻污染状态,除穿山南片和纸马铺外,其余采样点均有样本超过国家二级标准,其中七星公园东北片的土壤汞超标率较高,达71.4%,污染情况比较均一;虞山桥东南岸土壤汞超标率较低,为33.3%,但土壤汞含量变异较大,说明污染情况变化大。全市各片区老菜的汞含量平均值为0.0625-0.128mg/kg,为国家标准GB2762—1994规定蔬菜汞含量(0.01mg/kg)的6.25—12.8倍,超标率已达100%。实验还发现,蔬菜中的汞含量与土壤中的汞含量具有显著的相关性,且蔬菜汞的大部分分布于地上部可食部分。分析了菜地土壤汞污染的主要原因,可能与使用含汞农药和生活垃圾肥有关。  相似文献   

5.
新乡市郊区大棚菜地土壤重金属Pb、Cd、Cr和Hg污染评价   总被引:1,自引:0,他引:1  
周凯  王智芳  马玲玲  周丹  姚连芳 《生态环境》2013,(12):1962-1968
科学评估菜地土壤重金属污染对保障食品安全和公众身体健康具有重要的现实意义。采用原子吸收光谱法和冷原子吸收光谱法,研究了新乡市郊区菜地土壤重金属Pb、Cd、Cr和Hg的质量分数,并参照HJ 333-2006《温室蔬菜产地环境质量评价标准》,对土壤重金属污染进行评价。结果表明:菜地土壤重金属Cd、Pb、Cr、Hg的平均质量分数分别为25.64、156.18、992.38、0.316 mg·kg-1。东黑堆、前河头、后河头和东水东菜地土壤重金属Cd、Pb、Cr均全部超标,其中以Cd污染最为严重,后河头土壤重金属Cd的质量分数达到33.78 mg·kg-1,超过土壤环境质量评价指标限值的111.6倍,东水东采样点次之,也超标66倍。除了前辛庄Hg污染超标127%以外,其他采样点重金属Hg均不超标。表层(0~10 cm)土壤重金属Hg质量分数高于耕层(10~20 cm),其他重金属没有表现出明显的规律性。在不同季节,Cr质量分数随着季节变化逐渐递增,Hg质量分数则呈递减的趋势;Cd和Pb质量分数没有明显规律性。不同采样点综合污染指数以后河头的为最高,达到了82.49,其他依次为前河头、前辛庄、东黑堆、东水东。总体上讲,新乡市近郊菜地土壤重金属综合污染指数远远超过Ⅴ级的限值3.0,前河头、后河头和前辛庄菜地土壤都处于极高风险的重金属污染状态;东黑堆和东水东菜地土壤也处于高风险状态。  相似文献   

6.
郑州市环境空气中VOCs的污染特征及健康风险评价   总被引:6,自引:0,他引:6  
挥发性有机物(VOCs)不但是引发霾和光化学烟雾等环境问题的重要原因,达到一定浓度时还对人类健康造成威胁.为研究中原地区环境空气中VOCs 污染状况,探查VOCs 对人群健康产生的风险,以中原地区核心城市-郑州为代表,于2012年─2013 年间,在郑州市区内布点,以苏玛罐采样/气相色谱-质谱法分析测定了VOCs 的时空分布,并使用健康风险评价四步法进行健康风险评价.郑州市环境空气中VOCs 年均浓度分布特征:以烷烃和芳香烃为主,分别占总量的23.8%和19.5%;年平均质量浓度,芳香烃类为131 μg·m^-3、烷烃类为118 μg·m^-3,酮类为84.3 μg·m^-3、卤代烷烃类为67.8 μg·m-3;单体化合物以丙酮(66.2 μg·m-3)、乙醇(27.5 μ·m-3)、正十-烷(24.4 μg·m-3)和甲苯(17.2 μg·m-3)质量浓度最高,污染程度在国内居于中等水平.VOCs 季均浓度分布特征:夏季高于冬季,但各类化合物在两季的浓度差异较大.VOCs 日均浓度变化特征:烷烃类和芳烃类化合物于10:00 出现浓度峰值,浓度变化趋势与交通量变化具有相关性.健康风险评价结果为:非致癌风险大于1,会对人群健康造成-定的非致癌危害;苯、四氯化碳、1,2-二氯乙烷、1,1,2-三氯乙烷、六氯丁二烯的致癌指数超过EPA 致癌风险值,但未超出OSHA 致癌风险.  相似文献   

7.
综合水质标识指数法在浑河水质评价中的应用   总被引:12,自引:0,他引:12  
胡成  苏丹 《生态环境》2011,20(1):186-192
综合评价水环境质量,全面把握流域水环境污染特征是水环境污染防治中的重要基础性工作。水质标识指数可以完整标识水质评价指标的类别、水质数据、功能区目标值等重要信息,在单因子水质标识指数法基础上建立的综合水质标识指数法能完整表达河流总体的综合水质信息,既不会因个别水质指标较差就否定综合水质,又能对综合水质做出合理的评价;既可以在Ⅰ到Ⅴ类中比较水质的优劣,亦可以对劣Ⅴ类进行评价。为系统全面地研究浑河流域各不同河段水环境特征,将浑河流域划分为3个控制单元,根据2001—2010年间水质监测数据,采用综合水质标识指数法,识别出各控制单元主要污染因子,并阐明了浑河流域水环境质量时空变化规律,本研究即体现了全流域统筹考虑的系统思想,又体现了分区研究的针对性特点,并首次将综合水质标识指数法应用于浑河流域水质综合评价,其研究结论对水质监测数据的评价有一定的借鉴作用,亦对流域水污染防治对策的提出有一定的指导意义。  相似文献   

8.
As a result of economic development and population explosion, global ecological environments have been severely disturbed and markedly changed. An ecological crisis involving desertification, soil erosion, degradation of land quality, loss of biodiversity and global climate change has been brought about all over the world. In order to manage ecosystems efficiently, it is necessary to assess ecological risk at multiple scales. Ecological risk is the probability that a region and/or site will experience defined ecological or environmental problems. In this paper, the ecological risks of soil erosion, desertification, and acid deposition have been assessed on a national scale according to natural and human factors, such as topography, soil, vegetation and climate. This assessment has provided very useful information for ecological environmental management in China.  相似文献   

9.
我国水污染及饮用水源中有机污染物的危害   总被引:43,自引:0,他引:43  
本文阐述了我国水污染环境的状况和危害,以及微污染饮用水源的水质特征和饮用水源中的有机污染物及其危害。  相似文献   

10.
本文聚焦我国水生态保护与修复工作,结合长期实践,分析当前的形势和任务,指出了当前要着力解决的水生态问题主要是:在大坝上游,河流变湖库,生境变化导致生物物种变化;水库水流流速变缓,水体自净能力降低,导致富营养化及藻类水华.在大坝下游,清水下泄,冲刷下游河道导致局部河道河势变化较大;水库蓄水使坝下游春季水温下降、秋季水温升...  相似文献   

11.
Urban energy consumption is one of the most important causes of air pollution. Air pollution-oriented ecological risk assessment is of great significance to the promotion of urban environmental protection. This paper focuses on ecological risk in Xiamen city caused by air pollutant discharge from urban energy consumption. The Long-range Energy Alternatives Planning model was used to establish two scenarios of energy consumption in Xiamen city, and based on different scenarios, we estimated urban energy consumption and discharge quantity of air pollutant (DQAP). A box model and an expert scoring method were used to calculate the air pollution burden (APB) of SO2, NO2, CO, PM10 and PM2.5 and to obtain the probabilities of different air pollution loads. An ecological risk assessment model was developed and utilized to predict Xiamen city’s ecological risks in 2020. The results showed that under an energy-saving scenario, the ecological risks for PM2.5, SO2 and NO2 are high, whereas the ecological risks for CO and PM10 are low. Under a baseline scenario, the ecological risks for PM2.5, SO2 and NO2 are moderate, whereas the ecological risks for CO and PM10 are low. In addition, the APB of SO2, NO2, CO, and PM2.5, but not of PM10, is predicted to rise. In the simulation, energy generation from coal is the main source of air pollution. Although the DQAP from automobiles is not high, it is predicted to rise year-on-year. In summary, the ecological risk due to pollution in Xiamen city is high, and the main pollutants are SO2, NO2 and PM2.5.  相似文献   

12.
水污染对扬州市水资源存量的影响评价   总被引:1,自引:0,他引:1  
将水资源分成水资源的流量和存量两部分,估算了扬州市的水资源存量,提出了评价水污染对水资源存量影响的评价方法,并利用这种方法对扬州市水污染对水资源存量的影响进行了评价,得出了扬州市的水资源存量不足,而水污染又对水资源存量产生了较大的影响的结论。  相似文献   

13.
多介质土壤层系统处理旅游型村镇生活污水的示范研究   总被引:1,自引:0,他引:1  
采用投资少、处理费用低、运行管理简便的多介质土壤层(multi-soil-layering system,MSL)技术处理旅游型村镇———浙江省安吉县报福镇石岭村生活污水,该污水处理设施的日处理能力约为60 m3.d-1,系统稳定运行半年后的监测结果表明,整体系统对COD、TN、NH4+-N、TP及SS的平均去除率分别为82.7%、92.2%、94.1%、89.4%及97.1%,出水水质可稳定达到GB 18918—2002《城镇污水处理厂污染物排放标准》中的一级标准。  相似文献   

14.
The Common Agricultural Policy (CAP), a system of market support instruments, direct income transfers, and rural development measures, has been put through an ongoing reform process in recent decades. This paper introduces three policy impact assessment tools (SIAT, SEAMLESS-IF, MEA-Scope tool) and analyses how these tools have responded to a number of challenges for integrated assessment modelling as reported in the international literature. Significant progress has been made with regard to modelling linkages whereas other challenges, particularly those related to issues of scale and uncertainty management, require further efforts. It is also analysed which CAP instruments are represented and what kinds of effects can be analysed at different scales. Market instruments and direct payments are comparatively well represented, while the ability to model rural development measures is mostly beyond the scope of these tools. Because each tool has found a different solution for coping with the common challenges of integrated assessment modelling, the choice of one of the tools for a particular application depends strongly on the policy questions being asked. The SIAT provides the big picture via its ability to represent broad changes in policy instruments with EU-wide cross-sector impacts. The most comprehensive analysis of agricultural policy instruments can be obtained with SEAMLESS-IF. The MEA-Scope tool complements the other two approaches with detailed regional profiles.  相似文献   

15.
Urban ecological risk is one of the important factors that may restrict the social and economic development. Therefore, it is of great significance to carry out a comprehensive assessment of ecological risks so that an ecological risk prevention and control plan can be scientifically formulated. In this paper, a comprehensive ecological risk assessment indicator system of Xiamen was established based on local ecological properties and socioeconomic status. This indicator system covers seven indicators including air pollution, soil pollution, water pollution, fresh water consumption, change in land use, occupation of key zones with ecological functions, and road network expansion. Based on this indicator system and in conjunction with the single factor assessment of ecological risks, this study constructed a model of comprehensive ecological risk assessment and forecasted the comprehensive ecological risk of Xiamen in 2020. The results showed that the comprehensive ecological risk level of Xiamen in 2020 is medium and the main stressors are the discharge of air and water pollutants. From the perspective of risk receptors, i.e. the ecosystem services, the risk posed to the ecosystem services associated to the maintenance of air quality and water purification is the highest. Therefore, this study proposed the recommendations on ecological risk prevention and regulation in Xiamen based on the comprehensive assessment of ecological risks, in the hope to provide scientific support for local ecological protection and sustainable development.  相似文献   

16.
城市污水处理厂污泥处理处置的政策分析   总被引:8,自引:0,他引:8  
岑超平  张德见  韩琪 《生态环境》2005,14(5):803-806
简要介绍了城市污水处理厂污泥处理处置技术,提出污泥产业发展政策的建议,指出土地利用是符合我国国情的污泥处置的方向之一:污泥处理技术主要有减量化、浓缩、脱水、消化、堆肥等;污泥处置技术主要有焚烧、填埋、土地利用、建材利用等。污泥处理处置应按照减量化、稳定化、无害化原则,鼓励污泥资源化综合利用。合理确定污水处理厂污泥处理处置设施的布局和设计规模;鼓励对污泥处理处置给与税、费优惠政策,明确将污泥处理处置的运营费用列入污水排污收费范围,建立科学的价格补偿机制;政府在污泥产业发展中起着较为重要的作用,主要体现为服务与监督,包括承诺、保障和协调三个方面。  相似文献   

17.
The results of a study of photocatalytic degradation of phenol using aqueous oxygenated TiO2 (anatase) suspensions in a batch Pyrex photoreactor are reported. The influence on the photodegradation rate of various parameters as pH, phenol and TiO2 content, oxygen partial pressure, anions present in the dispersions was investigated. A complete oxidation of phenol was observed. Intermediate compounds, catechol and quinone, were detected. It was observed that the photodegradation also proceeded with sunlight radiation. A mechanistic and kinetic model, which accounts for the results obtained, is given. Likely reasons for inactivity of the rutile modification for this reaction are also given.  相似文献   

18.
长江口海域表层沉积物污染及其潜在生态风险评价   总被引:9,自引:0,他引:9  
根据2004年8月份长江口海域表层沉积物的监测基础资料,采用单因子污染参数法和Hakanson前在生态风险指数法,通过分析长江口不同水域表层沉积物中典型污染要素PCB,Hg,Cd,Pb,As的质量分数,评价了长江口表层沉积物的质量状况。定量确定了长江口表层沉积物的潜在生态风险程度、主要污染因子和潜在生态风险因子;分析了近年来长江口表层沉积物总的潜在生态风险和单个污染要素的潜在生态风险的变化趋势。结果表明:长江口表层沉积物质量状况良好,各典型污染要素的质量分数值均小于背景值,典型污染要素的平均综合指数Cd为1.37,典型污染要素的污染程度由高至低顺序为As>Pb>Hg>PCB>Cd,As是主要环境污染因子;长江口各水域表层沉积物总的对水域均只具有低潜在生态风险,其由高至低的排列顺序为杭州湾北岸>长江口南支>长江口北支>长江口外;各典型污染物对水域也均只具有低潜在生态风险,其由高至低顺序为Hg>PCB>Cd>As>Pb,Hg是主要潜在生态风险因子;近年来,长江口表层沉积物总的潜在生态风险和单个污染物的潜在生态风险均呈现增加趋势。  相似文献   

19.
钢铁工业区周边农业土壤中多环芳烃(PAHs)残留及评价   总被引:2,自引:0,他引:2  
对某大型矿业企业周边农业土壤中多环芳烃(PAHs)残留量进行了调查。结果表明,PAHs总残留量范围为312. 2~27 580. 9ng·g-1,且以4环以上多环芳烃组分为主。所有土样中均检出PAHs,单一污染物以芘、艹屈、荧蒽、苯并[a]芘、蒽、菲、苯并[a]蒽、苯并[k]荧蒽、茚并[1,2,3 cd]芘、苯并[g,h,i]苝为主。PAHs残留量与有机质含量相关性较好。不同样区土壤PAHs残留量受常年风向影响明显。以加拿大农业区域土壤PAHs的治理标准值为指标,用内梅罗综合指数法进行评价表明,研究区农业土壤达重污染水平的占37%,中度污染的占19%,轻污染的占25%,另有13%的采样点污染程度处于警戒限,仅有6%的采样点尚处于安全级。  相似文献   

20.
人工湿地对有机污染物的去除效果与动态特征   总被引:4,自引:0,他引:4  
通过对荣成人工湿地污水处理系统1999年1月至2004年12月间监测数据进行分析,确定系统的处理效果及有机污染物去除效果的动态特征。结果表明,人工湿地对SS、COD、BOD5均有很好的去除效果,出水质量浓度分别为27.6±6.6、90.0±12.5和22.7±4.3 mg.L-1,去除率分别为73.9%、63.8%和72.5%。大肠菌群、粪大肠菌群去除率分别为99.7%和99.6%。对NH4 -N和TP去除效果较差,出水质量浓度分别为11.2±2.7和2.03±0.29 mg.L-1,去除率分别为45.1%和30.2%。BOD5、COD的去除效果和季节变化有一定关系,每年的4—7月BOD5去除效果最佳,1月和12月去除效果最差。COD的去除效果每年6月和7月最高,1月和12月最低。分析BOD5、COD和SS去除效果的年际变化发现,BOD5和COD年平均去除率从1999年到2004年有增加的趋势。  相似文献   

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