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1.
河南省大气污染的气候分类   总被引:1,自引:0,他引:1  
分析确定了影响大气污染的主要气候因子,根据省内各气象站的常规观测资料,采用模糊聚类和纳污指数的方法将该省分成5个气候类型区,结果表明,纳污能力以中部地区为最强,占全省面积3/5的南、东、北邻管省界地区较强,豫西山区最弱。  相似文献   

2.
为确保2000-2010年桂林淳江上游进入城区水质能保持国家Ⅱ类水质标准进行纳污总量控制及其水质变化规律研究。采用系数法对200-2010年陆源排污总量进行科学预测,按河流功能划要求,首次利用动态数学模型计算河流在不同流量,不同纳污总量条件下保持Ⅱ类水质的最适纳污值,探讨了Li江水质变化规律。为环境管理打下基础。  相似文献   

3.
为确保 2 0 0 0 - 2 0 10年桂林漓江上游进入城区水质能保持国家II类水质标准进行纳污总量控制及其水质变化规律研究。采用系数法对 2 0 0 0 - 2 0 10年陆源排污总量进行科学预测 ,按河流功能区划要求 ,首次利用动态数学模型计算河流在不同流量、不同纳污总量条件下保持II类水质的最适纳污值 ,探讨了漓江水质变化规律。为环境管理打下基础  相似文献   

4.
蚯蚓对垃圾与底泥中镉的富集现象   总被引:1,自引:0,他引:1  
通过蚯蚓处理垃圾及纳污河流底泥实验研究发现蚯蚓可选择吸收并富集垃圾及底泥中的镉,但对其他重金属元素铅、铜、锌等并无此种富集吸收现象。  相似文献   

5.
蚯蚓对垃圾与底泥中镉的富集现象   总被引:28,自引:0,他引:28  
通过蚯蚓处理垃圾及纳污河流底泥实验研究发现蚯蚓可选择吸收并富集垃圾及底泥中的镉,但对其他重金属元素铅、铜、锌等并无此种富集吸收现象。  相似文献   

6.
本文介绍了模拟纳污水体中WAR,WMR,WCH,SAR,SMR,SSF和ROC的变化。过程曲线表明水体污染时底质参数出现累积现象。  相似文献   

7.
应用欧氏距离模糊相似优先比分析外省马尾松3个优良种源在浙江省各地区的推广适合度。取水分、热量和高、径生长量等9个相似因子,以原产地为固定样品比较省内5个试验点的适合度。分析结果与10年生试验林生庆观测结果基本吻合,贵港种源主要适于浙中、浙西地区,龙胜种源主要适于浙东、浙中地区,常宁种源主要适于浙中、浙南地区。  相似文献   

8.
中国土地荒漠化/土地退化的防治与环境保护   总被引:8,自引:1,他引:8  
朱震达  吴焕忠 《农村生态环境》1996,12(3):《农村生态环境》-1996年12卷3期,12(3)-96-96,12(3)页-《农村生态环境》-1996年12卷3期,12(3)-96-96,12(3)页
荒漠化是当今全球最严重的环境问题之一。结合中国国情来睦,荒漠化不仅发生于干旱、半干旱地区,也发生于湿润、半湿润地区。中国已慧的荒漠化土地面积111.7万km^2,占国土面积的11.6%;其中风力作用、水蚀作用和物理及化学作用下的荒漠化土地约各占1/3。另外中国还有易受风力和水力作用影响的潜在荒漠化土地53.5万km^2和87.5万km^2,潜在盐渍化土地17.3万km^2。中国土地荒漠化是在脆弱生  相似文献   

9.
对苏南地区城市化的特征和城市化过程中出现的环境问题进行了分析,指出城市化发展的必由之路是实行可持续发展,提出了该地区为实现可持续发展必须做到5个协调  相似文献   

10.
应用欧氏距离模糊相似倨先比分析外省马尾松3个优良咎源在浙江省各地区的适合度,取水分,热量和高,径生长量等92个相似因子,以原产地为固定样品比较省内5个试验点的适合度,分析结果与10年生试验林生长观测结果基本吻合,贵港种源主要适于浙中,浙西地区,龙中源主要适于浙东,浙中地区,常宁种源主要适于浙中,浙南地区。  相似文献   

11.
Eutrophication caused by the enrichment of nutrients from diffusing sources is degrading surface water quality throughout the world. Assessing the potential contributions of different land areas in diffuse nutrient export has become an important task in non-point source (NPS) pollution control. Existing methods were often limited by the availability of local data and the complexity of model formulation. This study developed a spatial multicriteria method to evaluate the nitrogen loss potential at the basin level. Four criteria were formulated to characterize the source capacity of nitrogen export, the flow path to water body, the efficiency of runoff generation and the climatic driving force. The proposed method is a low-effort approach since the required data is either already available in a global context or easily produced with limited inputs. Being implemented in GIS environment, this method generates maps that can be easily interpreted to provide decision support. The method was applied to the Huai River Basin, China. The results were validated based on the correlation between the nitrogen loss potential of sub-basin and the water quality class of river. The maps of nitrogen loss potential were helpful for examining the regional pattern of diffuse nitrogen loss, and could facilitate the decisions of NPS pollution management at the provincial or basin level.  相似文献   

12.
Coastal ecosystems generate diverse services, such as protection, production of food, climate regulation and recreation across the globe. These services are vital for extremely vulnerable coastal areas for enhancing present and future adaptation capacity under changing climate. Bangladesh has long coastline which provides opportunities to large population for multiple resource uses; and threats from extreme natural disasters. The CBACC-Coastal Afforestation is the priority initiative of Bangladesh NAPA that has come in actions under first LDCF adaptation project. The project has focused to reduce climatic vulnerability through enhancing resilience of coastal forests and adaptive capacity of communities. With a total of 6,100 ha of new mangrove plantation and introducing 10 important mangrove species in existing monoculture areas, the project increased protective and carbon rich forest coverage, and also functional capacity of coastal vegetation to adapt to current and future climatic shocks. Concurrently, the project developed co-benefit regime for community based adaptation through innovating integrated land uses for livelihoods of adjacent households. A new land use model (Forest, Fish and Fruit-Triple F) has been implemented to restore fallow coastal lands into community based livelihood adaptation practices. The Triple F practice has reduced inundation and salinity risks and freshwater scarcity in cultivation of agricultural crops and fish. The rational land uses improved household adaptation capacity of landless households through short-, mid- and long-term income generation. The project lesson has further focus to justify the land use innovation for harnessing potential opportunities of ecosystem based adaptation in coastal Bangladesh.  相似文献   

13.
城市现代化发展的生态防护研究——以南京市为例   总被引:4,自引:1,他引:4  
配合南京市总体规划的修订,研究城市现代化发展的生态建设途径。城市空间拓展应与地理生态背景相适用,生态防护网络是总体规划确定的三个圈层结构的组成部分,具有削减大气污染负荷,调节氧循环,改善城市环境的功能。  相似文献   

14.
广州市区大气污染特征与影响因子分析   总被引:9,自引:0,他引:9  
以2000—2004年广州市国控测点的空气环境质量自动监测结果为基础数据,以我国《大气环境质量标准》的日平均质量浓度二级标准为依据计算广州市2000—2004年的各大气污染物的指数及污染负荷率,阐明广州市区主要大气污染物SO2、NO2、PM10、CO的地域分布特征、季节变化特征、年际变化特征以及由于大气中的酸性物质而形成的酸雨的变化特征并提出研究对策。结果表明:各污染物质量浓度存在明显的季节变化规律,除SO2春夏秋季污染最严重,其余几项污染程度由高到低的顺序均为冬季,春季,秋季,夏季。近5年来空气中的一氧化碳呈显著下降趋势,但二氧化硫、二氧化氮和可吸入颗粒物则呈显著上升趋势,综合污染指数也呈明显上升趋势;酸雨频率呈不显著上升且夏秋季污染大于春冬两季。广州市大气污染分布规律与风向频率以北和东北偏北方向较大,东和东南方向次之的分布基本一致。  相似文献   

15.
The impact of climate changes on the pollution levels in Denmark is the major topic of this paper. Variations of the Danish air pollution levels that are caused by climatic changes are studied together with variations caused by other factors (emissions, inter-annual variability of meteorological conditions, etc.). The Unified Danish Eulerian Model (UNI-DEM) was run on a fine, 10 km × 10 km, grid over a space domain covering all of Europe to minimize the influence of the boundary conditions on the Danish pollution levels. This study is based on four categories of scenarios: (i) traditional scenarios, (ii) climatic scenarios, (iii) scenarios with variations of the human-made (anthropogenic) emissions and (iv) scenarios in which the biogenic emissions were varied. The total number of applied scenarios was 14, and a time-period of 16 years was used. The results show clearly that although the concentrations of the major pollutants do not depend too much on the climatic changes, some quantities, in particular quantities related to high ozone levels, might be increased significantly as a result of the warming trends in the future climate. The reason for this phenomenon is explained.  相似文献   

16.
A previous model of the global heat balance has been expanded by including the influence of SO2 pollution, water content of the atmosphere and cloudiness. It was found that the previous results were not changed significantly by this expansion of the model. The conclusions set up uising the previous model were still valid: (1) it is great importance to include the buffer capacity of the sea, including its dependence on pH and the temperature; (2) it is of importance to include natural climatic variations; (3) the dominanting factor is the trend in the consumption of fossil fuel.  相似文献   

17.
Effective management refers to the ability of a protected area or indigenous territory to meet its objectives, particularly as they relate to the protection of biodiversity and forest cover. Effective management is achieved through a process of consolidation, which among other things requires legally protecting sites, integrating sites into land‐use planning, developing and implementing management and resource‐use plans, and securing long‐term funding to pay for recurrent costs. Effectively managing all protected areas and indigenous territories in the Amazon may be needed to avoid a deforestation tipping point beyond which regional climatic feedbacks and global climate change interact to catalyze irreversible drying and savannization of large areas. At present, protected areas and indigenous territories cover 45.5% (3.55 million km2) of the Amazon, most of the 60–70% forest cover required to maintain hydrologic and climatic function. Three independent evaluations of a long‐term large‐scale philanthropic initiative in the Amazon yielded insights into the challenges and advances toward achieving effective management of protected areas and indigenous territories. Over the life of the initiative, management of sites has improved considerably, particularly with respect to management planning and capacity building, but few sites are effectively managed and many lack sufficient long‐term financing, adequate governance, support of nongovernmental organizations, and the means to withstand economic pressures. The time and money required to complete consolidation is still poorly understood, but it is clear that philanthropic funding is critical so long as essential funding needs are not met by governments and other sources, which could be on the order of decades. Despite challenges, it is encouraging that legal protection has expanded greatly and management of sites is improving steadily. Management of protected areas in other developing countries could be informed by improvements that have occurred in Amazonian countries.  相似文献   

18.
珠江三角洲土地利用变化对特征大气污染物扩散的影响   总被引:1,自引:0,他引:1  
在珠江三角洲两种下垫面条件下,应用CALPUFF大气污染扩散模式,对特征污染物SO2、SO42-的扩散进行数值模拟,探讨大规模土地利用变化,尤其是城镇建设用地增加,对珠江三角洲地区大气污染物扩散的影响,并通过对4个典型区污染物月均质量浓度变化特征分析,揭示土地利用变化对不同地区的污染物分布的影响机制。模拟结果表明:土地利用变化,尤其是城镇建设用地增加,不利于污染物扩散,污染源下风方向地区受影响较大,污染物质量浓度明显升高,SO2和 SO42-年均质量浓度分别增加14.07%和3.31%;受影响范围、变化幅度与污染源排污强度呈正相关,变化幅度亦与污染源距离远近呈负相关。土地利用变化后,尤其是城镇建设用地增加,四个典型区 SO2月均质量浓度都表现为升高趋势,且冬季 SO2质量浓度升高幅度最大,夏季升高幅度最小,临近污染源密集区的两个典型区SO2月均质量浓度分别增加33.6%和26.3%。土地利用变化不仅改变局地的污染扩散,也会对区域的污染扩散有一定影响,尤其对污染源分布密集区的大气污染物扩散影响强度最大。因此,建议人类在城市化建设过程中尽可能保留自然斑块,消除人工下垫面对污染物扩散的负面影响。  相似文献   

19.
To obtain comparable results of multi‐element analysis of plant materials by different laboratories, a harmonized sampling procedure for terrestrial and marine ecosystems is essential. The heterogeneous distribution of chemical elements in living organisms is influenced by different biological parameters. These parameters are mainly characterized by genetic predetermination, seasonal changes, edaphic and climatic conditions, and delocalization processes of chemical substances by metabolic activities.

The biological variations of the element content in plants were divided into 5 systematic levels, which are: 1. the plant species; 2. the population; 3. the stand (within an ecosystem); 4. the individual; and 5. the plant compartment. Each of these systematic levels can be related to: 1. genetic variabilities; 2. different climatic, edaphic and anthropogenic influences; 3. microclimatic or microedaphic conditions; 4. age of plants (stage of development), exposure to environmental influences (light, wind, pollution etc.), seasonal changes; and 5. transport and deposition of substances within the different plant compartments (organs, tissues, cells, organelles).

An expert system for random and systematic sampling for multi‐element analysis of environmental materials, such as plants, soils and precipitation is presented. After statistical division of the research area, the program provides advice for contamination‐free collection of environmental samples.  相似文献   

20.
对珠三角两个代表性乡镇工业区的土壤(沉积物)重金属污染现状和来源进行了评价。结果表明,两工业区在主要污染元素类型和综合污染程度上很相似,表层土壤(沉积物)均以Hg、As、Cu的污染为主,且均以Hg的污染最严重;但在某些次要污染元素种类以及某些主要、次要污染元素的单个元素污染程度上存在一些差异。柱样沉积物中重金属的变化特征进一步说明,两工业区土壤(沉积物)中重金属的累积与我国尤其是本地区的工农业发展阶段和发展水平密切相关。文章最后提出了乡镇工业区土壤(沉积物)重金属污染的几点建设性防治对策。  相似文献   

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