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1.
大庆油田湖泊湿地景观生态设计探讨   总被引:3,自引:1,他引:3  
采用景观生态设计的方法,将大庆油田职工生活居住区内湖泊湿地的湖盆、湖岸、湿地、水体及植物、地貌、土壤等自然因素作为一个整体,对湖底、湖岸、浅水区、湖滨带等地进行了景观生态设计。该设计方案体现了地方性特征,保护与节约了自然资源,显露了自然特色,达到了对环境影响最小、资本投入少、生态效益最大的设计目的。  相似文献   

2.
刘芳 《绿叶》2012,(9):73-81
如今,已经很难想象,当人们第一次开始运用化肥、农药、催熟剂、催红剂、膨大剂……等各类化学药剂时,曾经有过怎样的喜悦心情。这些化学药剂增加了产量、减少了病虫害、提高了农民收益、节约了人工投入、改善了各类农产品的商品卖相、降低了农业生产所存在的很多不确定风险。所以,"化学农业"替代了"传统农业",恐怕是一个必然的结果。尽管,"化学农业"给自然环境和人类健康带来了巨大的风险和危机。然而,人类社会的发展是一个永不停歇的过程,任何必然的结果都不可能因为其必然性而不被否决。事实上,只要当事物的结果不符合发展的内涵时,都必须予以反思,并寻找新的出路。  相似文献   

3.
贺雨辰 《绿叶》2012,(6):101-104
近几十年,我国经济建设高速迅猛发展,楼房高了、汽车多了、道路宽了、口袋鼓了,但同时,我们的生存环境也差了。如今,厚厚的灰霾像一个硕大无边的盖子整天罩在我们许多城市的上空,即使那些戴着"环保模范城市"、"生态示范区"、"生态市"、"宜居城市"桂冠的城市也是如此。我们的城市病了,钢筋水泥森林间流动的是污浊的空气。如果  相似文献   

4.
介绍了传感器的概念、原理、特点和分类,对近年来用于大气环境监测的二氧化硫、氮氧化物、二氧化碳、氨、甲烷和其他气体传感器的应用与研究进行了阐述,总结了用于大气环境监测的传感器的特点和局限性,展望了传感器在大气环境监测领域的应用与发展前景。  相似文献   

5.
《中国环境管理》2015,(2):50+73+78
《资源型企业创新能力评价》科学出版社陈泽明付红玲著出版日期:2015年3月29日定价:88元本书重点研究了生产要素、资源型企业、产业链、区域环境等构成的创新有源系统。揭示了系统的关联性、层次性、动态性、平衡性,分析了系统形成的一些机理。全面、准确、科学地建立了指标体系,评价了资源型企业的创新能力。提供了一种便捷评价企业创新能力的科学方法。  相似文献   

6.
党的十八大报告深刻体现了承前启后、继往开来、务实创新的精神,特别是突出了"12459"的量化任务和目标,进一步规划了我国科学发展、创新驱动、转型发展、可持续发展的蓝图,鼓舞人心、激励奋进,我们必须深入学习与领会。  相似文献   

7.
系统搜集了汉中、安康、商洛2002—2008年旅游收入、旅游客流量和GDP数据,利用"速度、质量、效益"模型,基于经济贡献率、增长弹性、拉动系数、产业结构和旅游就业5个指标,对陕南汉江走廊旅游开发带动区域发展进行了实证研究。结果显示,陕南3市旅游发展刺激陕南需求、拉动陕南内需,带动了相关产业的发展;3市旅游发展优化了陕南产业结构,促进了城市化进程,增加就业机会、促进了社会公平;3市旅游发展带动了陕南的经济增长;3市旅游发展对区域经济发展的带动程度各有不同,体现在不同层面,揭示了旅游发展带动区域经济的动态过程。  相似文献   

8.
现阶段,我国居民经济能力提高,出现了浪费型消费与攀比型消费,加上日益增长的人口数量,形成了一个巨大的"吞噬环境圈"。为了研究消费对环境的影响,本文立足于消费对碳排放量的影响,构建了STIRPAT模型,分析了人口数、城市化率、人均消费量、碳排放强度对碳排放总量的影响;得出了城市化率对碳排放量具有明显增加作用的结论;计算了人口数、城市化率、人均消费量的增长对碳排放增长量的贡献率,得出了人口数和人均消费量的变化对碳排放量的变化也有显著影响的结论;描述了我国五类消费品的增长情况;提出了消费方式从个人到企业,再到政府,最后到世界的转变过程与转变消费方式的路径,包括建立绿色GDP核算体系、进行绿色城市化、继续降低碳排放强度、加强教育和宣传以改变现存消费观、利用行政和法律实现节能低碳消费方式、重视新型能源技术的开发、拓展利用资源的广度和深度、加强国际交流与合作;最后,总结了改变物质主义价值取向和行为规范,完善绿色产品及基础设施的供给需要注意的三个方面。  相似文献   

9.
运用系统动力学构建了西递、宏村旅游地发展的系统动态模型,分析了西递、宏村游客市场结构,同时分析了模型建立下的西递、宏村近程观光市场和远程观光市场的发展机制反馈,并针对西递、宏村古村落目前旅游发展中存在的问题提出了调控对策和建议。  相似文献   

10.
朱建华 《环境技术》2009,27(6):47-53
NEBS认证,是电信网络设备进入北美地区电信网络的通行证。本文把获取NEBS认证的全过程划分为三个阶段,即准备阶段、设计阶段和实施阶段,并论述了各阶段的关键要点。首先,在准备阶段对NEBS进行了介绍,简要分析了NEBS认证的主要标准,同时指出运营商的特殊要求的重要性。接着分析了在设计阶段应该注意的技术点,如空间尺寸要求、电源输入、接地、防火、地震等。最后,讨论了认证测试阶段面临的困难,并强调了认证前摸底测试的重要性及必须具备足够的耐心。  相似文献   

11.
An attempt was made to investigate the relationship between raw coal characteristics and effluent quality in two coking coal washeries of Central Coalfields Limited, Kedla and Rajrappa in Jharkhand State, India. Coal samples-raw coal feed, washed fine clean coal, washed coarse clean coal, middlings and rejects were collected. Similarly, raw water (intake to washery) and effluent samples generated in the washeries, namely, fine coal jig under water, coarse coal jig under water and slurry pond water were also collected over a period of 6 months. Parameters outlined in Ministry of Environment and Forest (MoEF) Schedule VI Indian standards were determined, both in coal samples and water/washery effluent samples. Apart from the parameters listed in the standard, sodium, potassium, calcium, magnesium, sulphate and chloride found to be present in coal were also determined in coal and water samples. The processing results essentially in production of huge quantities of suspended material, which is beyond the stipulated limit of 100mg/l as specified in the Standard. Lowering of pH was observed in both the washeries. The trace/heavy elements were found to be concentrated in the heavier fractions in rejects produced from the washery. The concentrations of major elements in coal-Na, K, Ca, Mg, and minor elements in coal-Mn; F, SO4 and Cl were found to be higher in process water than in raw water indicating that these elements are transferred from coal to the water in washeries. However, only in the case of Mn, the stipulated limit of the effluent standard was exceeded. Trace elements like As, Se, Hg, Cd, though found to be present in coal, were absent in the process water indicating that these elements are not released by coal during washing.  相似文献   

12.
13.
This study analyzed the evolution of metal levels in surface sediments from the Guadalquivir estuary between 1997 and 2002 and assessed the impact of the April 1998 Aznalcollar tailings dam failure and subsequent cleanup on metal concentrations in surface sediments. We also analyzed metal distribution with time in five chemical fractions of the surface sediments: exchangable, carbonate, reducible, oxidizable, and residual. This work showed that the April 1998 Aznalcollar tailings dam failure caused a considerable increase in the concentrations of Cd, Zn, Cu, and Pb in the surface sediments of the Guadalquivir estuary. It was also found there was a change in the distribution of Cd, Zn, Cu, and Pb between the chemical fractions of the sediment after the failure of the dam. There were increases in the percentages of Cd in the carbonate fraction, of Zn and Pb in the reducible fraction, and of Cu in the oxidizable fraction, whereas the percentages of these elements associated with the residual fraction decreased. In 1999, there was a decrease in the metal concentrations in the surface sediments from the Guadalquivir estuary, and by 2000 the chemical distribution and metal levels had returned to levels similar those before the dam failure.  相似文献   

14.
This study evaluated the US Clean Water Act (CWA) Section 303(d) listing and delisting processes, based on historical and current federal and state guidelines, to determine whether there are regional differences in water quality assessment criteria used by various states to determine impairment of a waterbody for inclusion in the 303(d) list. A review of almost 50 total maximum daily load (TMDL) and delisting documents revealed that the basis for listing or delisting a waterbody varies considerably and that, in many cases, determination of impairment was based on insufficient water quality information. Historical USEPA guidance on the 303(d) listing and delisting processes has been generally broad, resulting in wide interpretation of the assessment criteria by various states. This has led to unclear or conflicting listing methodologies among states, leading to inconsistencies in impairment determination. Common problems include inconsistent data quality and quantity, differences in frequency of monitoring, variable interpretation of narrative water quality standards, and differences in specificity of implementation and monitoring plans, resulting in significant difference in the basis for listing and delisting waterbodies. In response, several states have taken the initiative to provide much more specific guidance for their internal agencies. Listing and delisting criteria are generally clearer at the state level, but the development of differing state guidance documents has resulted in diversity in the development of the 303(d) lists and in the process of delisting a waterbody. While state guidelines are better able to address local considerations, such as variations in climate, landuse, and water quality objectives, as well as social and economic preferences, the variation in listing criteria has led to inconsistencies across state boundaries in the levels of attainment of national water quality objectives. For stakeholders that participate in the 303(d) listing process within a particular state, these types of discrepancies may not have a significant impact. However, these inconsistencies can lead to confusion for some stakeholders who participate in the process in multiples states, and must deal with differing and sometimes conflicting requirements depending on the location of their facilities.  相似文献   

15.
The influence of slash-and-burn agriculture and tree extraction on the spatial and temporal pattern of forest fragmentation in two municipalities in the highlands of Chiapas, Mexico was analyzed. The data series were derived from two subsets of satellite images taken in 1974 and 1996. The analysis was based on area, edge, shape, core area, and neighbor indices. During the 22 years, the dense forest decreased by 8.9%/yr in Huistán and by 8.6%/yr in Chanal, while open/disturbed forest, secondary vegetation, and developed area increased in both municipalities. The total number of fragments increased by 1.4%/yr and 2.3%/yr in Huistán and Chanal, respectively. Dense forest showed the highest increase in the number of fragments (6%/yr in Huistán and 12%/yr in Chanal), while edge length, core area, and number of dense forest core areas decreased. The larger fragments of dense forest present in 1974 were divided into smaller fragments in 1996; at the same time, they experienced a process of degradation toward open/disturbed forest and secondary vegetation. Two different fragmentation patterns could be distinguished based on agricultural or forestry activities. Forest fragmentation did not occur as a continuous process; the pattern and degree of fragmentation were functions of land tenure, environmental conditions, and productive activities. The prevalence of rather poor soil conditions, small-holdings, growing human population densities, increasing poverty, and the absence of alternative economic options will maintain a high rate of deforestation and forest fragmentation in the studied region.  相似文献   

16.
ABSTRACT: Spatial and temporal variability in rainfall concentrations of nutrients, major ions, and herbicides was monitored at 7 locations in or near the Conodoguinet Creek watershed in south-central Pennsylvania from 1991.1993. Results were used to (1) compare precipitation quality in forested, agricultural and urban areas, and (2) assess the practicality of using volunteer citizen monitoring in such a study. As indicated in previous studies, sulfate and nitrogen concentrations in precipitation were linked to sample pH. Concentrations of major ions in precipitation appeared to relate more to regional influences rather than local influences. However, concentrations of herbicides in precipitation may have been influenced by both regional and local use which caused compounds like atrazine, deethylatrazine, propazine, simazine, metolachior, alachlor, ametryn, and prometon to be present in detectable concentrations in rainfall. Seasonality was evident in nitrogen, sulfate, pH, and herbicide data and was suggested in calcium, iron, manganese, magnesium, orthophosphate, and chloride data. Agricultural weed control activities were probably responsible for the seasonal pattern in pesticide data which peaked in May and June. Tropical storm Danielle may have caused the apparent seasonal patterns for the other nine parameters. This storm did not follow the typical west to east movement pattern and consequently produced rainfall of relative high quality. A variety of quality assurance checks indicated that trained volunteer citizen monitors were successful participants in this intensive and extensive scientific study, collecting good quality samples in a timely manner. Without this kind of volunteer help, it is extremely difficult to complete studies that require sampling in response to natural events such as rainfall.  相似文献   

17.
/ An index of upland wildlife habitat was developed to investigate patterns and changes in habitat over time, using four years (1920, 1940, 1964, 1987) and the state of Illinois as an example. The index was composed of two subdivisions that described, at the county level, the quantity of wildlife habitat and a third subdivision that described farming disturbances that impacted the quality of the habitat. Data came from the US Census of Agriculture. The first subdivision that reflected quantity of habitat was called the wildlife habitat subdivision and was the sum of percentage woodland on farms, percentage farmland in nonrow crops, and percentage farmland in set-aside programs. The second subdivision that reflected the quantity of habitat was termed the soil-related features subdivision and was the sum of the percentage of farmland that was not highly erodible, the percentage of farmland in soil-protecting crops, and the percentage of farmland in conservation tillage. The third subdivision, reflecting the quality of the habitat, was the farming disturbance subdivision and was the sum of the percentage of grazing and the percentage of land on which fertilizers, pesticides, and herbicides were applied. Overall, major decreases occurred between 1920 and 1987 in the subdivisions reflecting the quantity of wildlife habitat and a major increase occurred in the subdivision associated with farming disturbance, reflecting the intensification of agriculture in the state. However, there was variability throughout the state, with some counties being more favorable to wildlife (as measured by the subdivisions) than others. Most of the changes within the state for the subdivisions reflecting quantity of upland wildlife habitat occurred during 1940 while changes in the farming disturbance subdivision (reflecting habitat quality) occurred in 1964. By 1987, the western and southern parts of Illinois were the most favorable for wildlife as reflected in all three subdivisions. Upland wildlife harvest indices were related to the subdivisions in 1964 and 1987, when harvest indices were available. Cottontail and northern bobwhite harvests were higher in counties with higher amounts of the wildlife habitat subdivision in both years. Cottontail harvest was also higher in counties with lower levels of the farming disturbance subdivision in 1964 and higher levels of soil-related features subdivision in 1987. Indices at the county level have the potential to be used in a multiscale analysis to investigate the impact of policy changes on large-scale areas of the Midwest and to develop regional perspectives of the impacts of agriculture on upland wildlife and their habitats.KEY WORDS: Upland wildlife; Habitat; Agriculture; Illinois  相似文献   

18.
微塑料作为环境介质中的新型污染物,其对生态系统的影响越来越受到关注.土壤是环境中微塑料的重要蓄积库,结合近些年来国内外关于土壤中微塑料的研究,针对土壤中微塑料的来源、生态效应、分析方法及污染防治进行综述,以便更全面的了解土壤中微塑料污染的现状及其潜在的生态环境风险.塑料包装废弃物、农用地膜破碎、大气沉降是土壤中微塑料的...  相似文献   

19.
Electromagnetic field sources used for communication always have been subject of serious interest. There are many publications concerning exposure and risk assessment of the working in such environment. Results of epidemiological study performed in Bulgaria in the 1990's show exceeding of the maximal permissible values especially in radio stations for the personnel in 24 h working shift [Israel et al. (1992). Study of the electromagnetic in its influence on personnel working in radio and TV stations, Report, National Centre of Hygiene, Medical Ecology and Nutrition; Israel and Tomov (2001). Epidemiological study of the effects of radiofrequency radiation on operators in radio, TV and relay stations, Proceeding of the Eastern European Regional Meeting and Workshop “Measurements and Criteria for Standard Harmonization in the field of EMF Exposure” and WHO EMF Standards Harmonization Meeting, Varna, Bulgaria, 28 April—3 May, 2001, pp.145–153]. In the last years the situation is strongly influenced by the development of the technology which leads to changes in equipment in radio and TV stations, using lower power, facilitate the working regime. The paper presents data of exposure assessment of different professional groups in selected radio and TV stations. Assessment is being performed on basis of EMF parameters values and energetic load calculations according to the national legislation. Data are compared with the results of previous investigation to evaluate the new situation in this branch. Exposure levels are much lower than those in the previous study, and lower compared to the exposure limits, as well [Israel et al. (1992). Study of the electromagnetic in its influence on personnel working in radio and TV stations, Report, National Centre of Hygiene, Medical Ecology and Nutrition; Israel and Tomov (2001). Epidemiological study of the effects of radiofrequency radiation on operators in radio, TV and relay stations, Proceeding of the Eastern European Regional Meeting and␣Workshop “Measurements and Criteria for Standard Harmonization in the field of EMF Exposure” and WHO EMF Standards Harmonization Meeting, Varna, Bulgaria, 28 April—3 May, 2001, pp.145–153].  相似文献   

20.
ABSTRACT: Cyto-embryological analyses of fish eggs collected in nature can be a more sensitive indicator of environmental pollution than more typical assays conducted on artificially-spawned eggs. This is because uncertainties associated with artificial spawning and rearing are dispensed with, as well as because of the sensitivity of some cellular and subcellular analyses. At the same time, such measures can provide information on interannual differences in egg viability of importance in elucidating great, unexplained variability in fisheries recruitment. Extensive experience with fish embryos from ocean plankton has led to the choice of a particularly useful, practical suite of observations for different developmental stages. This includes measures of embryo mortality, mutagenicity, teratogenicity, abnormal cell differentiation, and development rate. Atlantic mackerel egg mortality has been determined to be greater in the surface waters of the New York Bight apex and along the New Jersey coast than in less polluted portions of the Bight. Chromosome abnormality of mid-stage embryos was also greater in more impacted areas of the same water mass, as well as in the somatic cells of adult mackerel and winter flounder, and in juvenile and adult windowpane flounder caught in more impacted areas. Mortality and abnormality of the mackerel embryos showed statistical associations with toxic hydrocarbons as measured in plankton, and with heavy metals as measured in sea surface waters. The sensitivity, practicality, and relevance of the cytoembryological studies to population dynamics of resource species make this an important means of monitoring environmental quality.  相似文献   

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