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1.
文章阐述了脉冲激励型静电除尘电源的发展历程,分析了两种典型脉冲激励静电除尘电源拓扑的优缺点,并针对采用高压开关方式的脉冲型静电除尘电源进行了研究,提出了设计思路,进行了仿真分析,建立了10kV直流叠加10kV脉冲电源系统并验证了设计的可行性;采用晶闸管研制了20kV/300A高压开关模块,并进行了实验验证。  相似文献   

2.
徐家保 《环境教育》2013,(11):48-51
生态文明建设为东海近年来的高速发展提供了保障,也为新一轮跨越式发展创造了良好的条件并奠定了扎实的基础。增强了城市的综合竞争力,提升了全民的生活品质,推动了社会事业的协调发展。  相似文献   

3.
中国环境科技管理研究会于今年10月在成都召开了第二次会员代表大会。会议听取了上一届理事会工作报告;修改了研究会章程;改选了第二届理事会;审议修改了受国家环保局委托起草的《深化环境科技体制改革意见》;开展了学术交流。  相似文献   

4.
同志们: 省第三次环境保护会议开了三天,今天就要结束了,这次会议开得很好,国家环保局的张副局长参加和指导了我们的会议,马麟同志作了报告。会议传达了第三次全国环境保护会议精神,认真学习了李鹏总理、宋健国务委员在会议上的重要讲话。马麟同志代表省环境保护委员会总结了过去五年的工作,并提出了今后的任务和完成任务的主要  相似文献   

5.
论述了青岛市农村环境保护工作的开展情况,详细分析了农村环境污染现状,探讨了症结所在,并提出了农村环境保护的对策。  相似文献   

6.
自节能减排目标被纳入"十一五"规划以来,国家相关各部委及各级政府采取了一系列措施开展了对SO2的全面控制工作,并提前一年实现了既定目标。本文简述了我国SO2减排的现状,分析了当前火电脱硫行业的特点,对即将到来的"十二五"火电脱硫行业的发展提出了建议并进行了展望。  相似文献   

7.
东小区是一个美丽的小区。春天,小区四周的柳树发芽了,桃花、迎春花和玉兰花开了,松柏比冬天苍翠了,花坛里盛开着红的、黄的、白的、蓝的、紫的等颜色的小花。小草绿了,大雁也从南方飞回来了,整个小区像是一幅美丽的画卷。夏天,大树的枝叶长得郁郁葱葱,茂盛的枝叶挡住了人们的视线。花坛里茉莉花、丁香花、月季花开了,给小区增添了不少光彩。秋天,小草渐渐地黄了,树叶也慢  相似文献   

8.
本文分析评价了温州市农业资源,农业开发条件与潜力,提出了农业区域开发的指导思想,总体目标与主要任务,确定了农业商品生产基地,划分了农业开发区,阐述了农业区域开发的对策与措施。  相似文献   

9.
我的家乡     
张莲莲 《环境教育》2014,(10):82-82
正春,风尘扑扑地来了。她停在了我的家乡——张家峪,这个群山环抱的小山沟里的小村庄。绵绵的细雨飘飘洒洒,树变绿了,山也绿了。地里的小草像从花棉袄里怯怯地露出了头来。夏,飞快地来了。我们村的小河被暖洋洋的微风吹开了一道道波纹,微微地荡漾着。许多人都说:"小鸭子们下水了。小鸭子们在水里乐开了花。"可  相似文献   

10.
系统分析了范庄油田污水处理中水质状况,找出了不达标的原因,提出了如下改进方案:合理加药,强化除油,加强沉降,严格过滤,自动排污,改善收油系统,改进处理工艺流程。实施改进措施后,有效地减少了地层污染,提高了污水回注率,避免了污水外排,同时还减轻了一线工人的劳动强度。  相似文献   

11.
Land uses such as forestry and agriculture are presumed to degrade the biodiversity of riparian wetlands in the northern temperate regions of the United States. In order to improve land use decision making in this landscape, floral and faunal communities of 15 riparian wetlands associated with low-order streams were related to their surrounding land cover to establish which organismal groups are affected by anthropogenic disturbance and whether these impacts are scale-specific. Study sites were chosen to represent a gradient of disturbance. Vascular plants of wet meadow and shrub carr communities, aquatic macro-invertebrates, amphibians, fish and birds were surveyed, and total abundance, species richness and Shannon diversity were calculated. For each site, anthropogenic disturbances were evaluated at local and landscape scales (500, 1000, 2500 and 5000 m from the site and the site catchment) from field surveys and a geographic information system (GIS). Land use data were grouped into six general land use types: urban, cultivated, rangeland, forest, wetland and water. Shrub carr vegetation, bird and fish diversity and richness generally decrease with increasing cultivation in the landscape. Amphibian abundance decreases and fish abundance increases as the proportions of open water and rangeland increases; bird diversity and richness increase with forest and wetland extent in the landscape. Wet meadow vegetation, aquatic macro-invertebrates, amphibians and fish respond to local disturbances or environmental conditions. Shrub carr vegetation, amphibians and birds are influenced by land use at relatively small landscape scales (500 and 1000 m), and fish respond to land use at larger landscape scales (2500, 5000 m and the catchment). Effective conservation planning for these riparian wetlands requires assessment of multiple organismal groups, different types of disturbance and several spatial scales.1998 Academic Press  相似文献   

12.
Large-scale infrastructural developments in rural areas often impose significant direct and indirect impacts on environment and people. The Three Gorges Project to dam the Yangtze River in China will create a huge reservoir, inundate farmlands and villages, and incur large-scale resettlement. The concurrent de-farming program to reforest marginal farmlands on steep slopes imposes additional stresses on local people. This study evaluates the ecological and economic adjustments in rural areas affected by both projects, and explores villagers’ knowledge, attitudes, perceptions, and expectations vis-à-vis the drastic changes. Eleven villages in Yunyang County in Sichuan Province, stratified into three zones based on topography and agriculture, were assessed by field studies, questionnaire surveys, maps, satellite imagery, and census and government reports. Multiple regressions identified predictors for 17 dependent variables. Spatial variations in the difficult terrain imposed zone-differentiated agricultural constraints, ecological impacts, and human responses. The dominant farming population—mainly young adults working as migrant laborers in cities—has adopted some nonagricultural work to supplement incomes. Expected per-capita standardized farmland (SF) exceeded threshold SF, which surpasses existing SF. Motivations to reclaim more farmlands, de-farm marginal lands, and become migrant laborers were explained by different multiple-regression predictors. Reduction in farmland stock by inundation and de-farming, aggravated by unwillingness towards nonlocal resettlement, would impose ecological pressures and stimulate demands for nonfarming incomes. Common anticipation of better future income and occupation has been subdued by unfavorable feedbacks from early relocatees. Future environmental and landscape changes are hinged upon changing human responses. Government policies could be informed by research findings to match economic, ecological, and social realities.  相似文献   

13.
Few quantitative studies have been done on the hydrology of fens, bogs, and mires. Consequently predicting the cumulative impacts of disturbances on their hydrologic functions is extremely difficult. For example, few data are available on the role of bogs and fens with respect to flood desynchronization and shoreline anchoring. However, recent studies suggest that very small amounts of groundwater discharge are sufficient to radically modify mire surface-water chemistry, and consequently, vegetation communities and their associated surface-water hydrology. Bogs and fens are, in a sense, hydrobiologic systems, and any evaluation of cumulative impacts will have to (1) consider the complicated and little understood interactions among wetland hydrology, water chemistry, and biota, and (2) place the effect of individual wetland impacts within the context of the cumulative impacts contributed to the watershed from other geomorphic areas and land uses.It is difficult to evaluate the potential cumulative impacts on wetland hydrology because geologic settings of wetlands are often complex and the methods used to measure wetland streamflow, groundwater flow, and evapotranspiration are inexact (Winter 1988). This is especially so for bogs, fens, and mires underlain by thick organic soils. These wetlands, found in the circumboreal areas of North America, Europe, and Asia, are major physiographic features in eastern North America, northern Europe, and Siberia (Kivenen and Pakarinen 1981, Gore 1983, Glaser and Janssens 1986). Their very scale makes it difficult to quantify the hydrologic function accurately. The hydrology of small bogs and fens found elsewhere is just as poorly understood because of conflicting conceptual models of pertinent hydrologic processes.This article (1) reviews our current understanding of the hydrologic function of bogs, fens, and mires at different scales and in different physiographic settings and (2) presents hypotheses on potential cumulative impacts on the hydrologic function that might occur with multiple disturbances.  相似文献   

14.
Urban ecological systems: scientific foundations and a decade of progress   总被引:9,自引:0,他引:9  
Urban ecological studies, including focus on cities, suburbs, and exurbs, while having deep roots in the early to mid 20th century, have burgeoned in the last several decades. We use the state factor approach to highlight the role of important aspects of climate, substrate, organisms, relief, and time in differentiating urban from non-urban areas, and for determining heterogeneity within spatially extensive metropolitan areas. In addition to reviewing key findings relevant to each state factor, we note the emergence of tentative "urban syndromes" concerning soils, streams, wildlife and plants, and homogenization of certain ecosystem functions, such as soil organic carbon dynamics. We note the utility of the ecosystem approach, the human ecosystem framework, and watersheds as integrative tools to tie information about multiple state factors together. The organismal component of urban complexes includes the social organization of the human population, and we review key modes by which human populations within urban areas are differentiated, and how such differentiation affects environmentally relevant actions. Emerging syntheses in land change science and ecological urban design are also summarized. The multifaceted frameworks and the growing urban knowledge base do however identify some pressing research needs.  相似文献   

15.
This study demonstrates the integration of rehabilitation and flood management planning in a steep, boulder-bedded stream in a coastal urban catchment on the South Island of New Zealand. The Water of Leith, the primary stream flowing through the city of Dunedin, is used as a case study. The catchment is steep, with a short time of concentration and rapid hydrologic response, and the lower stream reaches are highly channelized with floodplain encroachment, a high potential for debris flows, significant flood risks, and severely degraded aquatic habitat. Because the objectives for rehabilitation and flood management in urban catchments are often conflicting, a number of types of analyses at both the catchment and the reach scales and careful planning with stakeholder consultation were needed for successful rehabilitation efforts. This included modeling and analysis of catchment hydrology, fluvial geomorphologic assessment, analysis of water quality and aquatic ecology, hydraulic modeling and flood risk evaluation, detailed feasibility studies, and preliminary design to optimize multiple rehabilitation and flood management objectives. The study showed that all of these analyses were needed for integrated rehabilitation and flood management and that some incremental improvements in stream ecological health, aesthetics, and public recreational opportunities could be achieved in this challenging environment. These methods should be considered in a range of types of stream rehabilitation projects.  相似文献   

16.
The interactions between humans, animals and the environment have shaped human values and ethics, not only the genes that we are made of. The animal rights movement challenges human beings to reconsider interactions between humans and other animals, and maybe connected to the environmental movement that begs us to recognize the fact that there are symbiotic relationships between humans and all other organisms. The first part of this paper looks at types of bioethics, the implications of autonomy and the value of being alive. Then the level of consciousness of these relationships are explored in survey results from Asia and the Pacific, especially in the 1993 International Bioethics Survey conducted in Australia, Hong Kong, India, Israel, Japan, New Zealand, The Philippines, Russia, Singapore and Thailand. Very few mentioned animal consciousness in the survey, but there were more biocentric comments in Australia and Japan; and more comments with the idea of harmony including humans in Thailand. Comparisons between questions and surveys will also be made, in an attempt to describe what people imagine animal consciousness to be, and whether this relates to human ethics of the relationships. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

17.
In all, 13 stream water-quality parameters, including specific conductance (SC), pH, dissolved oxygen (DO), dissolved organic carbon (DOC), three nutrients, and six major ions were compared between the northern bedrock and southern coastal plain regions of New Jersey, USA and related to watershed-disturbance gradients characterized by the percentage of urban land, impervious surface (IS), agriculture, and altered land (sum of urban land and agriculture) in the watersheds. SC, DO, calcium, magnesium, sodium, and chloride concentrations were greater in the north. DOC was higher and pH was lower in the south. Nutrient, potassium, and sulfate concentrations did not differ between regions. Regional water-quality differences are attributed to geologic setting and land use. Except for DO in southern streams, all water-quality parameters were related to urban land, agriculture, or both. Significant correlations between urban land and IS and water-quality variables were similar in both regions with differences in unitless correlation coefficients ranging from 0.00 to 0.06. Compared to urban land and agriculture, relationships between most water-quality variables and altered land were stronger in the south. The extent of urban and agricultural lands in the watersheds did not differ by region. Altered land was correlated with urban land in both regions and with agriculture only in the south. Although focused on New Jersey, this study has broader implications for watershed planning.  相似文献   

18.
FAO has a unique and essential rolein addressing the ethical problems facinghumanity and in making these problems intoopportunities for practical resolution. A broadrange of ethical issues in agriculture,fisheries, and forestry were identified byanalysis of the literature and by interviewswith FAO staff. Issues include sharing accessto and preserving natural resources,introduction of new technology, conservatismover the use of genetic engineering, ethics inanimal agriculture, access to information, foodsecurity, sustainable rural development,ensuring participation of all people indecision making and in receiving benefits ofagriculture, reducing corruption, andinvolvement of private and public sectors indecision making. Rather than viewing theseissues as problems, they should be viewed asopportunities for debate, learning aboutothers' views, and resolution. The UnitedNations has an important role to play in howdecisions are made in the global ethical debatein food and agriculture. The ethical role ofFAO is to promote global food security,balanced conservation, management andutilization of natural resources, andsustainable rural development. FAO should fullyand publicly assume its ethicalresponsibilities, gathering and sharinginformation on ethics in its areas of mandate,acting as an interactive forum, and providingexpert guidance on policy options and choicesbased on practical ethical analysis.  相似文献   

19.
Interest in connectivity has increased in the aquatic sciences, partly because of its relevance to the Clean Water Act. This paper has two objectives: (1) provide a framework to understand hydrological, chemical, and biological connectivity, focusing on how headwater streams and wetlands connect to and contribute to rivers; and (2) briefly review methods to quantify hydrological and chemical connectivity. Streams and wetlands affect river structure and function by altering material and biological fluxes to the river; this depends on two factors: (1) functions within streams and wetlands that affect material fluxes; and (2) connectivity (or isolation) from streams and wetlands to rivers that allows (or prevents) material transport between systems. Connectivity can be described in terms of frequency, magnitude, duration, timing, and rate of change. It results from physical characteristics of a system, e.g., climate, soils, geology, topography, and the spatial distribution of aquatic components. Biological connectivity is also affected by traits and behavior of the biota. Connectivity can be altered by human impacts, often in complex ways. Because of variability in these factors, connectivity is not constant but varies over time and space. Connectivity can be quantified with field‐based methods, modeling, and remote sensing. Further studies using these methods are needed to classify and quantify connectivity of aquatic ecosystems and to understand how impacts affect connectivity.  相似文献   

20.
Is Amsterdam the “ideal city?” Many of the social, economic, and environmental problems facing Amsterdam are considerably less than those in cities in the USA, and in most cases, Western Europe. Amsterdam, at this moment in history, might be the world's greatest city because of its ability to ensure basic necessities, freedom, and creativity. Tolerance of drugs, sexual freedom, along with the integration of different races helps reduce many of the “social problems” faced by most cities. We have compared, on a per capita basis, differences between Amsterdam/Holland and the USA. The Netherlands is a tiny country, and comparisons are made on a city and per capita numbers at the national level. Our data show that Amsterdam has lower crime, murder, rape, drug usage (cocaine, marijuana), teenage pregnancy, diabetes, obesity, suicide, abortion rates, infant mortality, dependence on fossil fuels, and homelessness, and racial segregation is considerably less. People live longer because of Amsterdam's walkability and bike usage and access to parks. Indeed, the Netherlands leads both Western European and the USA in the proportion of trips made walking and bicycling, with significantly reduced car dependency. Ghettos are nearly non-existent compared with the segregation in the 1940s/1950s. Quality housing is supplied to everyone that gives pride of place compared with the stark, cold, and institutional “projects” provided by the US federal government. Amsterdam leads Western Europe by 35% in social housing, compared with runner-up UK, which has significantly less. The modernism of the 1960s where the poor were warehoused is nearly all gone. People living in Amsterdam seem more tolerant, secure, happier, and healthier compared with citizens in the USA. Great cities provide opportunities for all citizens to enhance their lives and ensure an unrivalled level of freedom. We demonstrate that social and environmental justice are tied together. Amsterdam is by no means perfect, but in comparison with many other democratic industrial cities, it is a far better place for citizens of all races, religions, and incomes.  相似文献   

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