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1.
晚新近纪亚洲内陆的干旱化趋势   总被引:1,自引:0,他引:1  
孙有斌  安芷生 《地学前缘》2002,9(2):285-286
本世纪以来 ,受全球增温和其它各种因素的影响 ,地球环境急剧恶化 ,对人类的生存和发展构成严重威胁。我国地处生存环境脆弱多变的东亚地区 ,在全球气候变化和社会经济高速发展的影响下 ,环境问题显得日益突出。其中尤以地处亚洲内陆的我国西北部地区的生态环境恶化最为严峻 ,干旱化及相伴的水资源短缺已成为制约西部经济可持续发展的重要区素。我国西北部地区的干旱化问题是继续加剧 ,或是有可能回暖到一个相对湿润期 ?人类活动的影响和自然环境演变的相互关系究竟如何 ?要科学地回答上述问题 ,首先必须了解有人类活动的新近纪以来 ,亚洲内…  相似文献   

2.
人为地质灾害和地质环境   总被引:3,自引:2,他引:3  
本文论述了人为地质灾害的概念, 典型事例以及人为地质灾害与地质环境的相互关系。指出, 人为地质灾害是由于人类的工程经济活动而引起的地质灾害。人为地质灾害可导致地质环境恶化, 使环境质量下降;而地质环境恶化又可导致地质灾害的加重, 使灾害频度增大, 强度增高。  相似文献   

3.
当今人类社会 ,经济高速发展和生活方式快速变更 ,正在加剧环境质量的急剧退化 ,已严重地威胁着人类的健康生存和社会持续发展。环境质量是评判人类生存与发展环境好坏的尺度和表征。经济持续快速增长地区环境质量演变及持续发展研究已成为跨世纪的前沿课题。近年来 ,我国科学界从人类活动与地球表层系统相互作用与可持续发展的视角出发 ,对长江、珠江三角洲等社会经济快速发展地区的资源、环境与可持续发展进行的研究表明 ,对该地区有关人类活动、经济过程与环境质量演变 ,以及与经济社会持续发展的耦合关系尚有待深入认识和阐明。因此 ,以…  相似文献   

4.
我国城镇化进程中遭遇和诱发了一系列地质环境问题,这严重危及了城镇安全及可持续发展。为了实现地质环境自身良性演化及其可持续利用,保障城镇安全及其可持续发展,文章系统分析了地质环境综合评价中的人-地相互作用以及人-地相互关系,并基于可持续发展的人-地关系协调理论和地球系统科学思想,构建了评价的基本流程:1人类活动-地质环境相互作用机制研究;2人-地相互适应能力评价:地质环境脆弱性评价、地质环境适宜性与功能区划、地质环境承载力评价;3人-地相互关系评价:地质环境影响性评价、地质环境风险性评价;4人-地相互关系协调。所建立的城镇地质环境综合评价研究体系,是实现城镇可持续发展与地质环境良性演化的协同调控技术,可为城镇化进程中减灾防灾、国土规划与地质环境安全保障提供理论先导。  相似文献   

5.
可持续性发展与现代生态自然观   总被引:5,自引:0,他引:5  
赵玲  黄冬梅 《吉林地质》1998,17(1):51-54
人与自然的关系问题的关键是人类如何看待自己和对待自然。随着人类社会的发展,人与自然的矛盾性质和特点发生了时代性的变化,表现为人类生存环境意识的觉醒和人类对生活质量、目标的反省。为了人类的生存,人类必须理性的解决人与自然的关系,充分认识可持续性发展的重要性,树立现代生态自然观的思想,避免人类与生存环境之间关系的恶化,真正达到人与自然的协调进化。  相似文献   

6.
地球科学的任务在于揭示地球本身和其他天体对地球影响的基本规律,揭示人类活动与地球环境相互作用的效应,从而为优化开发、利用地球资源、防治自然灾害、保护和优化生态环境提供理论基础;为国土整治、大型工程建设及制定国家经济发展规划提供基础知识和资料;为探索地球与天体起源、生命与人类起源、人与环境相互关系的演变等重大基础理论问题提供科学依据。  相似文献   

7.
地球科学的任务在于揭示地球本身和其他天体对地球影响的基本规律,揭示人类活动与地球环境相互作用的效应,从而为优化开发利用地球资源、防治自然灾害、保护和优化生态环境提供理论基础;为国土整治、大型工程建设及制定国家经济发展规划提供基础知识和资料;为探索地球与天体起源、生命与人类起源、人与环境相互关系的演变等重大基础理论问题提供科学依据。  相似文献   

8.
莫杰 《中国地质》1998,(12):43-44
人类社会发展到今天,已面临着“人口剧增、资源匮乏和环境恶化”三大亟待解决的问题。人类继续生存和发展的出路是开发利用海洋资源,使用现代科学技术手段,调查研究海洋,开发利用海洋和保护海洋;发展海洋产业,从大海中索取更多的海洋资源,来满足人类社会  相似文献   

9.
论灾害和环境的交融与互馈   总被引:2,自引:0,他引:2  
环境为人类生存发展提供了空间和所需要的资源,因此是重要的基础性生产要素。自本世纪50年代以来,环境问题已成为世界关注的焦点,人类对环境的认识出现了两次飞跃性进展。大量事实表明,灾害与环境同是地球运动和人类社会经济活动的产物。环境是灾害活动的背景和基础,灾害是环境异常恶化的表现,二者相互作用,同步消长,形成密切的交融与互馈关系。在减灾行动中,只有把防灾抗灾和保护与治理环境有机地结合起来,才能取得充分的效果。  相似文献   

10.
现代地球系统科学——可持续发展战略的科学基础   总被引:9,自引:0,他引:9  
人类的发展战略正在发生根本性地转变,用可持续发展战略代替以传统工业为基础的发展战略已成为国际社会的共识。讨论了现代地球系统科学及其与可持续发展的关系等问题,认为在现代地球系统演变过程中,全球环境是基础,人类圈为主导;现代地球系统科学是可持续发展战略的科学基础;实施可持续发展战略必须协调人类圈和全球环境的关系等。  相似文献   

11.
全球变化科学的进展   总被引:39,自引:4,他引:39  
全球变化科学对揭示和理解人类赖以生存的地球系统运转的机制、变化规律及人类活动对地球表层环境系统的影响具有重要的意义。从深海氧同位素曲线的建立与米兰科维奇理论的发展、高分辨率冰芯记录的研究、短周期气候变化、突变事件的发现、南北半球古气候对比的研究以及我国学者对过去全球变化研究的贡献等角度论述了地球环境变化历史的研究进展;并在对温室效应和全球气候变暖、臭氧洞、土地利用和土地覆盖的变化以及水资源等研究和现代观测资料分析的基础上,阐述了人类活动对地球环境的影响;提出了当前全球变化科学研究的发展趋势以及在新世纪全球变化科学所面临的挑战。  相似文献   

12.
对地球系统科学的几点认识   总被引:13,自引:0,他引:13  
地球系统科学将是21世纪地球科学的主旋律,它被定义为:“将地球作为一个整体来伯全部知识;对地球的气圈、水圈、生物圈和岩石中的各种作用及各层圈间相互作用时间进行的研究”。此种学术思想可追溯到100多年前,见於文字也有近二十年。它对当代地学的发展起了重要的推动作用,有四个特点:地球现象的远距离相互联系、影响;内动力和外动力研究一体化;地质作用和生物作用研究一体化;一类活动作为地球系统的一部分。当前地球系统科学的发展也提出了一些新问题,主要的是:在学术思路上对与岩石圈有关的地质作用有所忽视;观察研究系统不全面;还未深人到资源形成和小环境的研究中。近年来的观测试验表明,发生在岩石圈的各种地质作用正积极参与垒球各圈层间的物质能量交换。对它们的忽视,可能正是目前一些生物地球化学循环模型无法平衡的原因。  相似文献   

13.
Sporopollen, when recorded in the sedimentary record, is a characterization factor of vegetation over geological time of an area; the grain-size characteristics are direct reflection of the hydrodynamic conditions. Based on analyses of high-time resolution sporopollen and grain size of a 55-cm-long sediment core of Dongping Lake, it is shown that the sedimentary environment and hydrodynamic processes of Dongping Lake have seen significant changes over the past 150 years. From 1855 to 1865, the lake is in a hydrostatic depositional environment, where submerged plants were in great abundance, emergent and floating-leaved aquatic plants were comparatively fewer, and reworked sporopollen fossils were not observed. These indicate a weak and stable hydrodynamic condition during this stage. However, fluctuation of Mz, amounts of clay and silt were present, which may be due to high volumes of sediments around Dongping Lake basin transported into Dongping Lake via the Yellow River during the early lake-forming stages. From 1865 to 1922, the lake is in a backswamp depositional environment, where aquatic plants are nearly nonexistent, appearing occasionally in some layers with relatively low abundance. Fern spores show a twofold increase in occurrence and reworked sporopollen fossils are frequently identified. All of these indicate a strong hydrodynamic condition and frequent environmental change. Grain-size characteristics also support this interpretation. From 1922 to 1961, aquatic plants appeared at the upper layers of this zone at relatively low amounts, and reworked sporopollen fossils were frequently identified. Grain-size characteristics show an obvious change in grain-size distribution, indicating a strong hydrodynamic condition and unstable depositional environment. These relationships were attributed to a backswamp depositional environment. From 1961 to 2007, Dongping Lake is in a hydrostatic depositional environment, where the hydrodynamic condition is weak and stable. Evidence for this is shown by a remarkable increase in submerged plants, a rapid decrease in fern spores, and occasional appearances of reworked sporopollen fossils in the lower part of the zone. However, grain-size characteristics reveal that fluctuation of Mz, amounts of clay, silt and sand are noticeable and frequent, which may be mainly related to impacts of ever-enhancing human activities in recent years.  相似文献   

14.
Social responses to climate change over human history have been widely discussed in academia over the last two decades. However, the transformation of the human–environment nexus crossing prehistoric and historic periods and the processes associated with it are not yet clearly understood. In this study, based on published works on radiocarbon dating, archaeobotany, zooarchaeology, and archaeological sites, together with a synthesis of historical documents and highresolution paleoclimatic records, we trace the extent to which human settlement patterns in the Hexi Corridor in northwestern China evolved in conjunction with climate change over the last 5,000 years. A total of 129 Neolithic, 126 Bronze Age, and 1,378 historical sites in the Hexi Corridor(n=1,633) were surveyed. Our results show that, in the Late Neolithic and Bronze Age periods(~2800–100 BC), climate change contributed to the transformation of subsistence strategies and the subsequent changes in human settlement patterns in the Hexi Corridor. The warm-humid climate in ~2800–2000 BC promoted millet agriculture and helped the Majiayao, Banshan, and Machang Cultures to flourish. The cold-dry climate in ~2000–100 BC resulted in the divergence and transformation of subsistence strategies in the Xichengyi–Qijia–Siba and Shajing–Shanma Cultures and in a shift in their settlement patterns. However, in the historical period(121 BC–AD 1911), human settlement patterns were primarily determined by geopolitics related to the alternating rule of regimes and frequent wars, especially in the Sui–Tang dynasties. We also find that trans-Eurasian cultural exchange since ~2000 BC improved social resilience to climate change in the Hexi Corridor, mediating the human–environment nexus there. Our findings may provide insights into how human societies reacted to climate change in arid and semi-arid environments over the long term.  相似文献   

15.
《Earth》2009,92(1-4):77-92
The hypoxic zone in the Baltic Sea has increased in area about four times since 1960 and widespread oxygen deficiency has severely reduced macro benthic communities below the halocline in the Baltic Proper and the Gulf of Finland, which in turn has affected food chain dynamics, fish habitats and fisheries in the entire Baltic Sea. The cause of increased hypoxia is believed to be enhanced eutrophication through increased anthropogenic input of nutrients, such as nitrogen and phosphorus. However, the spatial variability of hypoxia on long time-scales is poorly known: and so are the driving mechanisms. We review the occurrence of hypoxia in modern time (last c. 50 years), modern historical time (AD 1950–1800) and during the more distant past (the last c. 10 000 years) and explore the role of climate variability, environmental change and human impact. We present a compilation of proxy records of hypoxia (laminated sediments) based on long sediment cores from the Baltic Sea. The cumulated results show that the deeper depressions of the Baltic Sea have experienced intermittent hypoxia during most of the Holocene and that regular laminations started to form c. 8500–7800 cal. yr BP ago, in association with the formation of a permanent halocline at the transition between the Early Littorina Sea and the Littorina Sea s. str. Laminated sediments were deposited during three main periods (i.e. between c. 8000–4000, 2000–800 cal. yr BP and subsequent to AD 1800) which overlap the Holocene Thermal Maximum (c. 9000–5000 cal. yr BP), the Medieval Warm Period (c. AD 750–1200) and the modern historical period (AD 1800 to present) and coincide with intervals of high surface salinity (at least during the Littorina s. str.) and high total organic carbon content. This study implies that there may be a correlation between climate variability in the past and the state of the marine environment, where milder and dryer periods with less freshwater run-off correspond to increased salinities and higher accumulation of organic carbon resulting in amplified hypoxia and enlarged distribution of laminated sediments. We suggest that hydrology changes in the drainage area on long time-scales have, as well as the inflow of saltier North Sea waters, controlled the deep oxic conditions in the Baltic Sea and that such changes have followed the general Holocene climate development in Northwest Europe. Increased hypoxia during the Medieval Warm Period also correlates with large-scale changes in land use that occurred in much of the Baltic Sea watershed during the early-medieval expansion. We suggest that hypoxia during this period in the Baltic Sea was not only caused by climate, but increased human impact was most likely an additional trigger. Large areas of the Baltic Sea have experienced intermittent hypoxic from at least AD 1900 with laminated sediments present in the Gotland Basin in the Baltic Proper since then and up to present time. This period coincides with the industrial revolution in Northwestern Europe which started around AD 1850, when population grew, cutting of drainage ditches intensified, and agricultural and forest industry expanded extensively.  相似文献   

16.
《Gondwana Research》2013,23(3-4):761-771
The abundant and diverse assemblage of filamentous microbial fossils and associated organic matter permineralized in the ~ 3465 Ma Apex chert of northwestern Australia — widely regarded as among the oldest records of life — have been investigated intensively. First reported in 1987 and formally described in 1992 and 1993, the biogenicity of the Apex fossils was questioned in 2002 and in three subsequent reports. However, as is shown here by use of analytical techniques unavailable twenty years ago, the Apex filaments are now established to be bona fide fossil microbes composed of three-dimensionally cylindrical organic- (kerogenous-) walled cells. Backed by a large body of supporting evidence of similar age — other microfossils, stromatolites, and carbon isotopic data — it seems clear that microbial life was present and flourishing on the early Earth ~ 3500 Ma ago.  相似文献   

17.
5000 a BP以来辽西地区环境灾害事件与人地关系演变   总被引:5,自引:3,他引:2  
依据辽西地区牧场泥炭层中高分辨率的孢粉分析和炭屑含量统计资料, 并通过对辽西地区自然环境演变与人类文化变迁历史的研究, 5000 a BP来的环境恶化可分为4个灾变过程: 即5000~4400 a BP 寒冷事件、2700 a BP左右寒冷事件、辽金时代的农业开发以及明清战乱.前两个过程与全球性的气候波动同步, 并对早期文明的发展进程产生了重要影响.后两个过程主要是由人类活动因素造成的, 同时也叠加了自然因素.目前区域内的环境恶化主要是由后两个过程引起的.  相似文献   

18.
中国历史时期气候变化对社会发展的影响*   总被引:2,自引:0,他引:2       下载免费PDF全文
历史时期气候变化对社会发展的影响与人类适应问题,是当前全球变化领域的研究热点之一。近年来,在利用丰富的历史文献资料研究中国历史时期(特别是过去2000年时段)气候变化与人类社会相互作用的过程机理方面取得了一系列新成果。本文将其归纳为3个方面: 理论上,构建了基于粮食安全的气候影响传递过程分析框架;方法上,实现了服务于气候变化影响研究的、基于语义差异的历史社会经济序列定量重建;科学认识上,总结出“冷抑暖扬”而又福祸相依的宏观韵律。在此基础上,对未来研究需要进一步深化的方向进行了展望。  相似文献   

19.
琥珀是一类有机宝石,其经济价值和科学意义日益受到重视.琥珀是植物树脂的化石形式.本文综述了现代的和已绝灭的产树脂植物的种类与地史分布.现代的产树脂植物包括松柏类和诸多被子植物科,现代松柏类如南洋杉科的琥珀最早可追溯至晚三叠世—早侏罗世,但在白垩纪中期至中新世的地层中更为丰富.始新世以来,热带和亚热带被子植物来源的琥珀开始占优势地位.绝灭的产树脂植物包括繁盛于石炭—二叠纪的科达类和髓木类种子蕨以及石炭纪以来出现并已绝灭的一些松柏类裸子植物.目前已知最早的琥珀产自晚石炭世地层(距今约3.2亿年).琥珀中含丰富的动植物化石,为研究地球生命的演化历史提供了重要材料.  相似文献   

20.
宫进忠 《地球科学进展》2012,27(10):1153-1160
在地球演化历史上,第四纪是人类诞生、发展和壮大的时代,它所形成的地质产物中记录了丰富的生态环境信息。河北省境内第四纪岩石地层(泥河湾组、赤城组、马兰组、迁安组)的风化指数CIA,Fe2O3/FeO,Fe/Mn等地球化学参数可作为年均气温、年均降雨量等气候因子的近似代用指标;华北地区人类文化遗址所在地水系沉积物中Hg,Sn和Au等元素含量随人类文明的演进而阶段性增高。这一结果表明,人类为了适应不断变化的自然地理环境(寒冷、干旱),不得不进行技术创新,从而产生了农业耕作、工业革命及现代信息产业等文明进步成果,但与此同时,却也导致了地质环境的人为污染,甚至可能引发全球温室效应。  相似文献   

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