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1.
Atmospheric remote sensing from satellites is an essential component of the observational strategy deployed to monitor atmospheric pollution and changing composition. During this decade, remote sensors using the thermal infrared (TIR) spectral range have demonstrated their ability to sound the troposphere and provide global distribution for some of the key atmospheric species. This article illustrates three operational applications made possible with the IASI instrument onboard the European satellite MetOp, which opens new perspectives for routine observation of the evolution of atmospheric composition from space.  相似文献   

2.
近代由于气候的变暖,工业化进程的加快,人口的激增,森林的过度砍伐,草场的超载过牧,化学制品的滥用,环境的污染,生态环境遭到了严重破坏,生物物种灭绝速度较单纯自然状态下的速度要快1000倍。生物物种灭绝对人类生产、生活,甚至对人类生存都构成巨大的威胁。因此,应对气候变化,保护生物多样性,防止物种灭绝,已成为全球性的紧迫任务;中国是世界生物物种资源最丰富的国家之一。中国生物多样性形势总体严峻。中国政府高度重视生物多样性保护工作,先后颁布一系列法律法规,已收到巨大成效;保护生物多样性确保世界粮食安全,是全球人民的普遍愿望。生物灭绝关系人类存亡。人类要秉承天人合一的理念,与大自然和谐相处。  相似文献   

3.
为了解研究区土壤重金属环境质量状况,对土壤进行样品采集和测试。采用单因子污染指数法和内梅罗(Nemerow)综合污染指数法,依据《土壤环境质量标准》(GB15618--2008)第二级标准对土壤中Ni和Cd的污染状况进行环境风险评价。结果表明,Ni的污染范围主要在距中心点3 000 m范围内,超标点共15个,大部分超标点为轻微污染或轻度污染。个别点存在重度污染和综合污染现象。此外,对土壤重金属超标点位的玉米作物进行测试分析,发现其Ni和Cd含量均不超标,说明土壤的污染程度对于当地的玉米作物没有影响。  相似文献   

4.
对近年升空的CHAMP和GRACE和将于2007年升空的GOCE卫星在测定地球重力场方面的技术特点和初步成果进行了回顾、比较和评估。并对它们今后在静态和动态的地球重力场构模方面可能的进展作一展望。现在只用一颗重力卫星的轨道摄动数据,就可以以前所未有的可靠性和精确性来求定地球重力场的长波和部分中波。如CHAMP重力卫星的33个月数据所求定的地球重力场模型,相对于曾利用多颗卫星资料所推算的GR1M5 S1重力场模型,在长波方面的精度和可靠性都有很大改善。而GRACE重力卫星的 110天数据所导出成果的空间分辨率,又优于CHAMP的33个月的数据成果。GRACE卫星还有一个重要任务,就是测定重力场非潮汐的短期性或准实时的变化。还介绍了新发表的一个联合地球重力场模型EIGEN CG03C, 360完全阶次,分辨率约30′。CG03C同CHAMP/GRACE以前的重力场模型比较,在400 km波长的精度方面改善了一个量级,大地水准面的精度改善了3 cm,重力异常的精度改善了0.4 mgal。  相似文献   

5.
重力卫星五年运行对求定地球重力场模型的进展和展望   总被引:3,自引:0,他引:3  
陈俊勇 《地球科学进展》2006,21(7):661-666,T0001,T0002
对近年升空的CHAMP和GRACE和将于2007年升空的GOCE卫星在测定地球重力场方面的技术特点和初步成果进行了回顾、比较和评估。并对它们今后在静态和动态的地球重力场构模方面可能的进展作一展望。现在只用一颗重力卫星的轨道摄动数据,就可以以前所未有的可靠性和精确性来求定地球重力场的长波和部分中波。如CHAMP重力卫星的33个月数据所求定的地球重力场模型,相对于曾利用多颗卫星资料所推算的GRlM5-S1重力场模型,在长波方面的精度和可靠性都有很大改善。而GRACE重力卫星的110天数据所导出成果的空间分辨率,又优于CHAMP的33个月的数据成果。GRACE卫星还有一个重要任务,就是测定重力场非潮汐的短期性或准实时的变化。还介绍了新发表的一个联合地球重力场模型EIGEN-CG03C,360完全阶次,分辨率约30′。CG03C同CHAMP/GRACE以前的重力场模型比较,在400km波长的精度方面改善了一个量级,大地水准面的精度改善了3cm,重力异常的精度改善了0.4mgal。  相似文献   

6.
Clementine was a technology demonstration mission jointly sponsored by the Department of Defense (DOD) and NASA that was launched on January 25th, 1994. Its principal objective was to use the Moon, a near-Earth asteroid, and the spacecraft’s Interstage Adapter as targets to demonstrate lightweight sensor performance and several innovative spacecraft systems and technologies. The design, development, and operation of the Clementine spacecraft and ground system was performed by the Naval Research Laboratory. For over two months Clementine mapped the Moon, producing the first multispectral global digital map of the Moon, the first global topographic map, and contributing several other important scientific discoveries, including the possibility of ice at the lunar South Pole. New experiments or schedule modifications were made with minimal constraints, maximizing science return, thus creating a new paradigm for mission operations. Clementine was the first mission known to conduct an in-flight autonomous operations experiment. After leaving the Moon, Clementine suffered an onboard failure that caused cancellation of the asteroid rendezvous. Despite this setback, NASA and the DOD applied the lessons learned from the Clementine mission to later missions. Clementine set the standard against which new small spacecraft missions are commonly measured. More than any other mission, Clementine has the most influence (scientifically, technically, and operationally) on the lunar missions being planned for the next decade.  相似文献   

7.
《Applied Geochemistry》2001,16(11-12):1291-1308
Land degradation and pollution caused by population pressure and economic development pose a threat to the sustainability of the earth's surface, especially in tropical regions where a long history of chemical weathering has made the surface environment particularly fragile. Systematic baseline geochemical data provide a means of monitoring the state of the environment and identifying problem areas. Regional surveys have already been carried out in some countries, and with increased national and international funding they can be extended to cover the rest of the land surface of the globe. Preparations have been made, under the auspices of the International Union of Geological Surveys (IUGS) and the International Association of Geochemistry and Cosmochemistry (IAGC) for the establishment of just such an integrated global database.  相似文献   

8.
京津冀区域大气霾污染研究意义、现状及展望   总被引:15,自引:0,他引:15  
频发的霾污染是目前京津冀最严重的环境问题。如何协调区域经济合理快速发展与防止大气环境恶化,已经成为公众关注的焦点,也是各级政府亟待解决的问题之一。对国内外典型大气污染事件的产生及治理历程进行了简要回顾;结合我国当前霾污染问题产生的特殊性,分析了京津冀区域霾污染研究对经济和社会发展、气候和环境变化、人体健康和区域和谐发展的现实意义;阐述了京津冀霾污染现象频发的主要客观要素和内在原因,并分析了当前研究工作中的不足。最后,在全球气候变化的大背景下,推测了京津冀及东亚地区未来大气污染的发展趋势。  相似文献   

9.
Predicted changes in temperature during the next century and the possibility of substantial depletion of stratospheric ozone would represent an unprecedently rapid change in the global environment with enormous effects including important impacts on human health. These are likely to be most obvious in the Third World where some areas can expect an intencification of existing major health hazards: an increased frequency of floods and storms; changes to the availability of food and good quality domestic water supplies and climate-related changes in the ecology of insect vectors for diseases such as malaria. In developed countries significant impacts can be also be anticipated. More frequent episodes of hot weather could be associated with more food poisoning and with increases in deaths from circulatory diseases. These might be offset by lower mortality rates in warmer winters. Exposure to photochemical atmospheric pollution is likely to increase. Stratospheric ozone depletion together with more exposure to sun in warmer weather could accelerate the existing rise in the incidence of skin cancer and increase the risk of cataracts.  相似文献   

10.
Predicted changes in temperature during the next century and the possibility of substantial depletion of stratospheric ozone would represent an unprecedently rapid change in the global environment with enormous effects including important impacts on human health. These are likely to be most obvious in the Third World where some areas can expect an intensification of existing major health hazards: an increased frequency of floods and storms; changes to the availability of food and good quality domestic water supplies and climate-related changes in the ecology of insect vectors for diseases such as malaria. In developed countries significant impacts can also be anticipated. More frequent episodes of hot weather could be associated with more food poisoning and with increases in deaths from circulatory diseases. These might be offset by lower mortality rates in warmer winters. Exposure to photochemical atmospheric pollution is likely to increase. Stratospheric ozone depletion together with more exposure to sun in warmer weather could accelerate the existing rise in the incidence of skin cancer and increase the risk of cataracts.  相似文献   

11.
锑的环境生物地球化学循环与效应研究展望   总被引:13,自引:0,他引:13  
研究表明锑与铅和汞一样,是一个可长距离输送的全球性有毒元素;但锑的研究最近才引起国际社会的关注。与其它金属如汞、铅、镉和砷等相比,国际上锑的研究开展得相对较少。为了揭示锑的全球性污染程度、循环过程及其对生态环境的影响,急需开展深入研究。概述了前人在锑的环境生物地球化学循环和效应方面的研究成果,分析了存在的科学问题,凝练了进一步研究的方向、思路和方法,并指出我国西南地区是开展这一方向研究的理想区域,及在该地区开展深入研究的重要性。  相似文献   

12.
生物炭对土壤理化性质影响的研究进展   总被引:10,自引:0,他引:10  
Biochar is an organic material with high carbon content, most aromatic structure and great stability resulting from high temperature thermal conversion (usually < 700 ℃) of organic materials under the completely or in part anoxic condition. Due to its stable chemical properties, biochar has received widely attention as a strategy to reduce greenhouse gas emissions. In addition, biochar shows great potential in soil improvement and environmental pollution remediation, and provides a comprehensive solution for the global climate change, food crisis and ecological pollution remediation. Biochar is a carbon rich material, in association with porous characteristics and high surface area which are favorable to accumulating soil moisture, to increasing the porosity, to reducing density and bulk density, and to promoting the formation of soil aggregation. All the above soil physical improvement can provide a good environment for the growth of plants. Furthermore, biochar is an ideal acidic soil amendment which can improve the pH of acidic soil. It contains nutrient element which can be directly released into soil, and its surface charge and functional groups are conducive to soil nutrient retention, such as the reduced leaching of NH+4 and NO-3, PO3-4, therefore improve the efficiency of nutrient elements. However, the effect of biochar amendments highly influenced by raw materials and pyrolysis conditions is of inconsistent and sometimes even contrast results can be concluded. In this paper, we summarize the current status and knowledge gaps about the effect of biochar amendments on soil physical and chemical properties and some suggestions are also strengthened. Finally, some possible negative impacts of biochar application and research suggestions are discussed in order to better use of biochar in agriculture.  相似文献   

13.
CCOP stands for Coordinating Committee for Geoscience Programmes in East and Southeast Asia—an intergovernmental organization comprising of eleven Member Countries: Cambodia, China, Indonesia, Japan, Malaysia, Papua New Guinea, the Philippines, Republic of Korea, Singapore, Thailand and Vietnam. CCOP’s mission is to facilitate and coordinate the implementation of applied geoscience programmes in the region to contribute to economic development and an improved quality of life within the region. As an intergovernmental geoscience organization, CCOP organizes its activities in seven programmes, including the groundwater programme, which promotes capacity building, technology transfer, exchange of information and institutional linkages for sustainable groundwater resource development in CCOP Member Countries. The overview of the status of groundwater development within the CCOP Member Countries will be elaborated highlighting quantity and quality challenges for its sustainable development. Some examples of challenges are the large numbers of people in these regions that still have no access to an improved water source; decline in the availability of freshwater, particularly in large river basins due to global warming; saltwater intrusion; arsenic pollution of groundwater, etc. Finally, the emphasis of the importance of capacity building in sound groundwater management will be shown as the contribution of CCOP to its members. The recommendation to capture the opportunities for groundwater development in CCOP Member Countries will be presented and discussed.  相似文献   

14.
安徽省地质碳汇潜力及二氧化碳地质储存   总被引:2,自引:0,他引:2  
方星  孙健  魏永霞 《安徽地质》2010,20(2):81-84,89
气候变化是当今全球面临的重大挑战,它不仅是重大的科学问题,也是重大的政治问题。遏制气候变暖,拯救地球家园,是全人类共同的使命。我省处于工业化加速期,高能耗行业比重高,未来面临巨大的二氧化碳减排压力。加大产业结构调整、利用低碳技术改造和提升高碳产业固然是非常重要的技术措施,但地质碳汇也是二氧化碳减排的一条重要渠道。岩溶碳汇效应显著,土壤固碳潜力巨大,在二氧化碳减排和缓解温室气体效应的研究计划中,加强地质研究已是不容回避的重大科学问题。  相似文献   

15.
Whilst satellite radar altimetry has been widely utilised over both ocean and ice surfaces for topographic mapping, applications over land have received relatively little attention. This is in part due to the complex nature of echoes returned from rapidly varying topographic land surfaces, which can cause an altimeter to generate erroneous range estimates. One approach to improving these data is to retrack using a single retracker, and construct a spatial average of heights obtained to give an estimate of mean orthometric height. This paper presents results obtained using an alternative approach: reprocessing returns at all levels of complexity through an expert system, which chooses one from a series of ten reprocessing algorithms based on an analysis of the return waveform shape. The selected algorithm then recalculates the range to surface, and hence derives an orthometric height. Utilising this approach with the geodetic mission dataset from ERS-1 has generated over 100 million height points with a near-global distribution. This paper presents selected results from this research using ERS-1 geodetic mission data together with ERS-1 and ERS-2 35 day data to demonstrate the accuracy to which orthometric heights can be determined, using global crossover analysis and comparison with ground truth. The paper illustrates applications of these data including validation and error correction of Digital Elevation Models, and discusses use and limitations of direct mapping with altimetry.  相似文献   

16.
环境沉积学的兴起   总被引:1,自引:0,他引:1  
鲜本忠  姜在兴 《沉积学报》2005,23(4):677-682
面对生态、环境、灾害、全球变化等重大问题和环境科学、沉积学的发展,环境沉积学应运而生。环境沉积学的发展经历了萌芽和兴起2个阶段,直至20世纪90年代中后期,其研究始得以广泛关注。在前人研究的基础上,初步厘定了环境沉积学的概念和研究目的,指出其研究内容既包括沉积学中的环境问题,又包括环境科学中的沉积问题,4个研究方向分别为原生环境沉积学、污染物环境沉积学、生态环境沉积学和全球变化环境沉积学。环境沉积学以环境和灾害研究为己任,将在解决人类面临的环境污染、生态破坏、地质灾害、全球气候变化等重大问题的研究中发挥越来越重要的作用,是未来沉积学发展的重要方向之一。  相似文献   

17.
非线性水污染控制系统规划的遗传算法   总被引:6,自引:0,他引:6  
水污染控制系统规划常采用最优化方法和模拟法相结合的方法,不仅计算繁琐,而且很难保证得到的解全局最优。本文给出了一种求解非线性水污染控制系统规划的遗传算法(GA),应用GA一次性求出污水系统规划最佳方案,比常规的方法更为简洁,而且能够保证得到的解全局最优。   相似文献   

18.
基于GIS的农业面源硝酸盐地下水污染动态风险评价   总被引:1,自引:0,他引:1  
地下水中的硝酸盐污染具有全球性,这不仅是一个环境问题,也是一个经济和人类健康问题。DRASTIC方法可以进行地下水污染的脆弱性评价,但是却没有涵盖风险的概念,也忽视了污染物随地表水流运动的动态特性。因此,所得结果可能有碍于“欧洲水管理框架指南”在地下水水质管理中的执行。笔者基于DRASTIC方法开发了一个动态风险评价方法,并将其运用于英国北爱尔兰Upper Bann流域中的一个小流域。研究区地下水硝酸盐污染风险评价结果表明,此方法将有效地帮助决策者在流域范围内开展农业面源地下水污染预防措施。“非常高风险”和“高风险”区分别占研究区面积的5.1%和10.5%。此结果可帮助当地政府针对流域内这些“非常高风险”和“高风险”区的特点制订地下水质保护政策。此方法同样适用于任何面源可溶性污染物的地下水污染动态风险评价。  相似文献   

19.
Populations and metropolitan centers are accumulated in coastal areas around the world. In view of the fact that they are geographically adjacent to coasts and intense anthropogenic activities, increasing global offshore pollution has been an important worldwide concern over the past several decades and has become a very serious problem that needs to be addressed urgently. Due to offshore pollution, various geological disasters occur in high frequency, including intensified erosion and salinization of coastal soils, frequent geological collapses and landslides and increasing seismic activities. Moreover, offshore pollution shows increasingly serious impacts on the topography and geomorphology of offshore and coastal areas, including coastal degradation, retreating coastlines and estuary delta erosion. Offshore sedimentation processes are strongly influenced by the pH changes of terrestrial discharges, and sedimentary dynamics have become extremely acute and complex due to offshore pollution. The seabed topography and hydrodynamic environment determine the fate and transport of pollutants entering offshore regions. Coastal estuaries, port basins and lagoons that have relatively moderate ocean currents and winds are more likely to accumulate pollutants. Offshore regions and undersea canyons can be used as conduits for transporting pollutants from the continent to the seabed. It is particularly noteworthy that the spatial/temporal distribution of species, community structures, and ecological functions in offshore areas have undergone unprecedented changes in recent decades. Due to increasing offshore pollution, the stable succession and development trend of marine ecosystems has been broken. It is thus important to identify and regulate the quantity, composition and transportation of pollutants in offshore regions and their behavior in marine ecosystems. In particular, crucial actions for stabilizing marine ecosystems, including increasing species and biodiversity, should be implemented to enhance their anti-interference capabilities. This review provides an overview of the current situation of offshore pollution, as well as major trends of pollutant fate and transportation from continent to marine ecosystems, transformation of pollutants in sediments, and their bioaccumulation and diffusion. This study retrospectively reviews the long-term geological evolution of offshore pollution from the perspective of marine geology, and analyses their long-term potential impacts on marine ecosystems. Due to ecological risks associated with pollutants released from offshore sediments, more research on the influence of global offshore pollution based on marine geology is undoubtedly needed.  相似文献   

20.
地下水污染场地风险管理与修复技术筛选   总被引:4,自引:0,他引:4  
国际上对于地下水污染场地的控制与修复研究已经取得了许多成果,已有成功的修复实例。我国虽然起步晚,但非常重视地下水污染的防治,开展了全国范围的地下水污染调查,并进行了地下水污染的防治规划。地下水污染的控制与修复已经逐渐进入示范性研究阶段。面对地下水污染场地风险管理的不同方法,以及众多的污染修复技术,如何制定风险管理策略,如何在各种各样的修复技术中筛选合适的技术或技术组合,对于地下水污染场地的防治具有非常重要的意义。笔者分析了发达国家地下水污染风险管理策略,结合在地下水污染场地研究方面的经验,对一些主要的地下水污染修复技术进行了分析论述,提出了考虑污染物特征、场地水文地质条件的地下水污染修复技术的筛选过程和方法。  相似文献   

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