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涠西南凹陷是中国近海北部湾盆地已证实的富烃凹陷,始新统流沙港组是该凹陷主要烃源岩层系.为深入认识涠西南凹陷流沙港组烃源岩的生产力和发育特征,采用有机地球化学与地球生物学相结合、定性分析与定量计算相结合的方法正演恢复了涠西南凹陷不同次洼流沙港组不同层段烃源岩的古生产力、有机质埋藏效率和有机碳埋藏生产力,进而建立了研究区流沙港组烃源岩形成的地球生物学模式.结果表明,涠西南凹陷流沙港组烃源岩的古生产力、有机质埋藏效率及有机碳埋藏生产力在横向不同次洼和纵向不同层段上均存在差异,横向上以B次洼最优,纵向上以流二段最高;涠西南凹陷流沙港组烃源岩发育超营养湖高埋藏效率高埋藏生产力、富营养湖中等埋藏效率中等埋藏生产力及富营养湖低埋藏效率低埋藏生产力3种代表性的地球生物学模式. 相似文献
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在全球变化背景下,湖泊水文的动态变化不仅是评估和预测气候与环境变化的重要指示剂,同时对社会可持续发展、水资源的开发与利用、生态文明建设等产生重要影响。湖泊水文的动态变化受到湖滨及湖底地形的控制,数字高程模型（DEM）成为湖泊水文研究的重要数据源。随着遥测技术的发展,高分辨率、区域/全球大尺度DEM数据的获取手段快速发展、数据源不断丰富,DEM对推动湖泊水文动态研究进展起到了关键作用。本文首先基于Web of Science平台对DEM在湖泊水文动态研究中的相关文献进行了分析,阐述了该主题现有研究在发文时间、发文数量增减态势、研究区域与热点地区、文献所涉及的DEM数据等方面的特点。接着,围绕着DEM在湖泊水文动态的研究中4个主要方向：湖泊水域变化、湖泊水位变化、湖泊水量变化、湖泊水文灾害情势,重点总结：DEM与其他遥感观测平台、实地观测及模型模拟等多源数据的融合策略,数字地形分析与水文学分析、遥感影像分析等方法的集成策略,以及DEM数据不确定性等对湖泊水文变化研究的影响。最后,本文论述了目前DEM在湖泊水文研究中存在的关键问题,并结合技术发展趋势和研究热点问题,提出了可能的解决路径和未来的研究前景。 相似文献
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According to palaeoclimatic and modern instrumental data, numerous studies have indicated that the Arctic climate has undergone a significant warming during the past 100 years, and this may lead to significant impact on the fragile lake ecosystem. In this study, we collected a lake sediment core from the Ny-(A)lesund of Svalbard and determined the concentrations of four pigments including chlorophyll derivatives, total carotenoids, oscillaxanthin and myxoxanthophyll in the sediments. Combined with other physical and chemical proxies such as calcium carbonate, total organic carbon, biogenic silicon etc., we have reconstructed the historical changes of lacustrine primary productivity in Ny-(A)lesund, especially for the past 100 years. The results showed that during the period of Little Ice Age (LIA), the climate was unfavorable for the growth of the lake algae, and thus the lacustrine productivity declined. This result was supported by the relatively low contents of pigment and biogenic silica in the sediments. In contrast, the contents of total organic carbon (TOC) and sediment pigments increased significantly in the upper 5 cm (~1890AD), reflecting the rapid growth of the lake algae, thus the great increase of lacustrine primary productivity, corresponding to the warming climate after LIA. However, the biogenic silica in the upper sediments still had a relatively low level, and this might be related to the growth competition with other algae species. Over the past 100 years, the ratio of Osc/Myx in the sediments decreased continuously, indicative of durative increase of myxoxanthophyll in blue-green algal pigments, and this might imply that the human activity had enhanced the nutrition level of the lake in the Arctic region. 相似文献
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1OVERFLOWBURSTOFMORAINELAKEFloodwater and debris flow caused by glacial lake burst is an important land process and a serious moun-tain disaster in glacial area. Glacial lakes with burst can divided into the glacier-obstructed lake (ice dam lake) and the terminal moraine lake (XU and FENG, 1988). Typical burst of ice dam lake happens in the modern glacier area of the upper reaches of the Kele-qing River in Uygur Autonomous Region of Xinjiang (WANG, 1990). But most of burst gla… 相似文献
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阎百兴 《中国地理科学(英文版)》1998,8(4):352-361
Ｉ．ＩＮＴＲＯＤＵＣＴＩＯＮＭｏｓｔｖｏｌｃａｎｏｅｓａｒｅｄｉｓｔｒｉｂｕｔｅｄｉｎｎｏｒｔｈｅａｓｔｏｆＣｈｉｎａ．Ｔｈｅｖｏｌｃａｎｉｃｅｒｕｐｔｉｏｎｓｃａｎｃｈａｎｇｅｔｈｅｇｅｎｅｒａｌｍｏｒｐｈｏｌｏｇｉｃｃｏｎｆｉｇｕｒａｔｉｏｎｏｆ... 相似文献
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近百年来龙感湖地区湖泊营养化过程 总被引：5，自引：0，他引：5
由于近年来社会经济的迅速发展，湖泊富营养化问题日趋严重。其中湿地的破坏是导致人湖营养盐增加的一个重要原因。对湿地变化与湖泊营养盐状况关系的分析是制定湖泊环境整治和生态修复的重要科学依据。湖泊沉积物含有丰富的生物和理化方面的信息，在缺乏长期湖泊监测记录的情况下。可以用来重建湖泊及其流域过去变化的历史。根据龙感湖表层沉积物^210Pb活度比变化，分析了该地区近百年来沉积物中湿地花粉、总磷和磁性参数．探讨了湖泊营养化过程及机理。研究表明，龙感湖近百年来营养级的增加是与湿生植被的破坏密切相关。20世纪上半叶的湖泊富营养化响应于磁性参数指示的流域土壤侵蚀速率的增加，而20世纪70年代以来湖泊营养程度的加重则与龙感湖流域农业化肥的使用和湿地植被破坏而导致湿地功能减弱有关。龙感湖流域内人类对湖周潍地的改造．破坏了湿地植被，助长了人湖物质的增加。湖泊营养相对富集，最终导致水体富营养化发生。 相似文献
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王东 《广东海洋大学学报》1989,(Z1)
本文应用模糊综合评判理论和方法,把正常湖泊分为五种营养类型,选用总氮、总磷、硅盐、浮游植物和浮游动物五个参数评介湖泊营养化程度。对湖泊营养类型分类进行了开拓性研究。 相似文献
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INTRODUCTIONThedistingnishingc~teristicsofQinghaboe,thebiewstsalinelakeinCfuna,are:vastwaterm,higheleVation,closeddrinagbasinandattrativenaedland-scape.The~clakeleveldIDPsincethebegiwhngofthiscentwhascausedaseriesofenvironrnntalProblems(degenndionofghanggIaSSlandaIDunthelake,desertffica-tioninthebeacharea,aeOianerosionoftheeXposedlakebed,deCrainwaersuPPliesandincreaseinthewaterndnends).IncentalAsia,mostofthewell-knOWnlargelakes,includingla.kessuchasIssyk-kul(SeVaStyanvandSndmov,l… 相似文献
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该文在查明区域水文地质条件、湖区地下水的类型、分布、埋藏条件、含水层及隔水层特征、岩性结构以及地下水的补给、径流、排泄条件的基础上,通过现场试验,确定了天然状态下湖区各含水层之间的水力联系、黄河侧渗补给量及湖区向小清河的排泄量,结合数值模拟,预测了湖区维持设计蓄水位21.5m时黄河的侧渗补给量、湖区向小清河的排泄量及湖区对周边地下水位的影响。结果表明,天然状态下,黄河侧渗补给量为748.23m~3/d,湖区向小清河排泄量大约为52.03m~3/d,黄河侧渗补给量远大于湖区向小清河的排泄量。数值模拟结果表明,湖区维持设计蓄水位21.5m时,不同水文年湖区接受的侧渗补给量均大于湖区的渗漏量,且对周围地下水位的影响不超过1.5m,因此,湖区维持设计蓄水位21.5m时可不考虑防渗措施。 相似文献
13.
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秦伯强 《中国海洋湖沼学报》1993,11(4):314-320
The rapid shrinkage of the surface area reflects the long-term deficit water budget of Qinghai Lake. Study of the yearly hydrology and meteorology in the lake catchment basin and the hydrologic factors as well as water budget led to the conclusion that evaporation exceeding the water input resulted in the drop of lake level, thai the obvious decrease of runoff to the lake and precipitation on the catchment accelerated the falling of lake level before 1987. and that increase of about 6.7% in rainfall on the whole basin will balance the lake's water budget. 相似文献
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Heavy metal research in lacustrine sediment： a review 总被引：2，自引：0，他引：2
Heavy metals are released into environment from a wide range of natural and anthropogenic sources. Aquatic ecosystems are normally at the receiving end and in many cases, with lakes as intermediaries. Lacustrine sediments are important sinks for heavy metals and play a significant role in enrichment and remobilization of heavy metals in aquatic systems. Therefore, characteristics of heavy metal in lacustrine sediments become one of the important issues in environmental sciences. Progress in heavy metal research of lake sediments since late 1980s is reviewed comprehensively in this paper from over 100. The Highlights are placed on the establishment of aquatic sediment quality guidelines, references chemical speciation of heavy metals, heavy metal transport mechanisms in lakes, and high-resolution study of lake borehole cores. Meanwhile, suggestions for heavy metal research in lacustrine sediment in the future are proposed, including such issues as using integrated approaches to assess aquatic ecosystem, modem lake dynamic process, high-resolution evolutionary sequence and spatial differentiation of environments and international lake database, which should be referential to the promotion of research on heavy metal in aquatic system. 相似文献
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根据现代科学技术水平的发展,定义了盐湖资源与环境的科学概念,表述了盐湖资源的范畴和内涵,对盐湖的水面位、相环境、成岩作用、变质作用及反馈作用进行了详悉论述;对盐湖系统研究的几个关键性问题及发展方向和应用前景进行了讨论。 相似文献
17.
CHENG Xiaoying LI Shijie SHEN Qing XUE Jing 《中国地理科学(英文版)》2007,17(1):69-74
To study the influence of human activity on natural lake, chironomid fauna change in the 700–560cm lake sediment in Quidenham Mere of England associated with chironomid inferred TP presented that the lake experienced a whole eutrophication process due to human hemp-retting in Post-Medieval based on the history record and pollen analysis, which was confirmed by mollusc and ostracod analysis. However, the response of chironomid and mollusc to retting was the strongest with ostracod a little behind. It proved that cultural eutrophication existed in history and could be recovered by itself despite of some long-term unachievable destroy. And it was most important for external nutrient to be cut off during lake restoration even in ancient times. 相似文献
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刘天仇 《中国地理科学(英文版)》1995,5(4):344-354
ＳＴＵＤＩＥＳＯＮＷＡＴＥＲＳＴＡＧＥＦＬＵＣＴＵＡＴＩＯＮＯＦＹＡＭＺＨＯＬＡＫＥＩＮＸＩＺＡＮＧＬｉｕＴｉａｎｃｈｏｕ（刘天仇）（ＴｉｂｅｔａｎＢｕｒｅａｕｏｆＷａｔｅｒＲｅｓｏｕｒｃｅａｎｄＨｙｄｒｏｌｏｇｉｃａｌＳｕｒｖｅｙ，Ｌｈａｓａ３５０... 相似文献
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The lake groups in the Songnen Plain are low plain lake groups, which are located in the temperate semihumid area in China.
They are characterized by small area, shallow basin, thick density and various types. In the try for classifying comprehensively
the lake groups, a classification system is developed based on three main factors, i.e. forming cause, water quantity and
water quality. The most internal character can be concisely grasped through three principal indexes and three auxiliary indexes
of three main factors. A sample of complicated changeable path is put forward for further analyzing and outlining these basic
types, in the meantime, it’s linking up easily with the classification system of the single factor. According to the regional
environment, the regional differences of the type composition and the principal types, the lake groups in the Songnen Plain
can be divided into 6 sub-regions.
Foundation item: Under the auspices of the National Natural Science Foundation of China(49671077).
Biography: LU Jin-fu (1938–), male, professor. His research interest includes paleo-environment in the Quaternary. 相似文献
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THE RELATIONSHIP BETWEEN INLAND LAKES EVOLUTION AND CLIMATIC FLUCTUATION IN ARID ZONE 总被引：2，自引：0，他引：2
The evolution of the inland lakes in arid and semi-arid zones is accorded with the climatic fluctuation. The humid climate is in harmony with the higher water level and greater lake water quantity budget while arid climate is in correspondence with the lower water level and little water budget. Based on the analysis of the lake fluctuation and lake budget change, with the aid of the data of geom'orphology, palynology, sedimentology and chronology, It is found that the climate experienced a warm and humid period during 7000-3500 yr. B. P. and showed a drying and warming trend in the last century in the Central Asia. 相似文献