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海湾分类系统研究 被引量:23
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作者 吴桑云 王文海 《海洋学报》 CAS CSCD 北大核心 2000年第4期83-89,共7页
在全国海湾调查的基础上,将《中国海湾志》所记载的96个海湾的基本要素进行了统计分析,选择了海湾的水域率、开敞度、形态系数、动力参数等量化指标,对中国海湾分类进行定量化划分的探索,同时对海湾的成因分类也进行了有益的探讨.
关键词 海湾 分类 量化 海岸
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黄渤海辽宁省海湾的环境现状及其评价 被引量:11
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作者 马嘉蕊 邵秘华 +1 位作者 鲍永恩 殷金生 《环境科学研究》 EI CAS CSCD 1995年第1期27-34,共8页
以1987~1990年海湾环境调查资料为基础,探讨了位起东部北黄海的青堆子湾(东经123°25′05E,北纬39°45′50″N).,西止渤海的锦州湾(东经121°04′55″E,北纬40°47′22... 以1987~1990年海湾环境调查资料为基础,探讨了位起东部北黄海的青堆子湾(东经123°25′05E,北纬39°45′50″N).,西止渤海的锦州湾(东经121°04′55″E,北纬40°47′22″N)的辽宁省共13个海湾水质、底质和生物中化学要素含量分布,得到广诸海湾污染程度是:除污染物锅外,重金属为底质>生物>水质;系统阐述了各海湾的环境质量现状及化学要素的超标情况,为今后选划各湾的适养区,治理环境污染提供了科学依据。 展开更多
关键词 海湾 化学要素 评价 黄渤海 环境质量 辽宁省
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海湾开发利用强度分析——以宁波市杭州湾、象山港与宁波市三门湾为例 被引量:11
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作者 李加林 姜忆湄 +5 位作者 冯佰香 黄日鹏 何改丽 王丽佳 田鹏 刘瑞清 《应用海洋学学报》 CSCD 北大核心 2018年第4期541-550,共10页
海湾开发利用强度评估可反映海湾利用程度,是海湾开发潜力及其可持续开发研究的基础,对发展湾区经济意义重大.以1990—2015年每隔5 a共6期TM/ETM/OLI影像为数据源,提取宁波市杭州湾、象山港和宁波市三门湾各时期的岸线及土地利用数据,... 海湾开发利用强度评估可反映海湾利用程度,是海湾开发潜力及其可持续开发研究的基础,对发展湾区经济意义重大.以1990—2015年每隔5 a共6期TM/ETM/OLI影像为数据源,提取宁波市杭州湾、象山港和宁波市三门湾各时期的岸线及土地利用数据,基于此从海湾岸线开发和土地利用两方面综合分析海湾开发利用强度及其变化特征.结果表明:1990—2015年间,宁波3湾岸线人工化程度不断加深,岸线人工化指数最高的海湾由象山港(0. 16)转变为宁波市三门湾(0. 61),部分淤泥岸段(尤其是宁波市杭州湾岸段)滩涂围垦强度弱于泥沙淤积强度,削弱了岸线人工化程度.整个研究期间,宁波市三门湾和宁波市杭州湾的岸线开发利用结构始终为单一主体结构,象山港则呈现出由单一主体依次向二元、多元结构演变的趋势. 1990—2015年间,宁波3湾的岸线和土地利用强度均有所增加,其中象山港岸线开发利用强度指数最大,达0. 42;宁波市杭州湾区域土地利用变动最为强烈,土地利用程度指数最大,达292. 300.区位和资源禀赋、社会经济水平及政策因素是造成宁波3湾区域开发利用程度差异的重要因素. 展开更多
关键词 海洋环境科学 开发利用强度 岸线人工化程度 土地利用程度 湾区经济 海湾
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小样本条件下装备作战效能评估问题研究 被引量:3
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作者 张家宾 《计算机与数字工程》 2021年第8期1516-1519,1565,共5页
作战效能评估一般指武器装备在相应的作战背景下,针对具体的作战对手的作战能力的评估。对能力的评估需要作战试验、军事演习等重大活动数据的积累,但由于试验成本、兵力短缺、环境构设复杂等条件的限制,作战效能评估的准确度、置信度... 作战效能评估一般指武器装备在相应的作战背景下,针对具体的作战对手的作战能力的评估。对能力的评估需要作战试验、军事演习等重大活动数据的积累,但由于试验成本、兵力短缺、环境构设复杂等条件的限制,作战效能评估的准确度、置信度一直受制于所需样本量的不足。文章针对传统小样本问题处理方法的缺点,引出Bays Bootstrap方法,并实例验证了该方法的合理性以及在区间估计等方面的精确性等优势。最后将该方法应用于某舰艇作战试验中对空拦截能力的作战效能评估,提高了结果的置信度。 展开更多
关键词 小样本 区间估计 作战效能评估 bays Bootstrap方法
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基于间隔的图模一体化电网拓扑的分析方法 被引量:4
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作者 周磊 黄学良 《电气技术》 2009年第1期56-60,共5页
间隔是一组相互电气关联的完成一定功能的设备集合。本文基于图模一体化编辑工具的电网编辑工具形成的原始静态拓扑,提出了一种面向间隔的分析方法,将变电站中的设备按包含了基本连接关系的间隔进行归类,并且将结果保存在关系数据库中... 间隔是一组相互电气关联的完成一定功能的设备集合。本文基于图模一体化编辑工具的电网编辑工具形成的原始静态拓扑,提出了一种面向间隔的分析方法,将变电站中的设备按包含了基本连接关系的间隔进行归类,并且将结果保存在关系数据库中。生成的间隔拓扑可以提供给倒闸规则生成,间隔状态分析和变电所、调度智能倒闸开票所用。基于B/S模式的实际应用,证明了该方法的可靠性。 展开更多
关键词 间隔 静态电网拓扑 B/S模式
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Younger Dryas Comet 12,900 BP 被引量:1
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作者 Hermann G. W. Burchard 《Open Journal of Geology》 2017年第2期193-199,共7页
Deep troughs in Lake Superior support the hypothesis of Younger Dryas Boundary (YDB) comet impact 12,900 BP. The impact theory explains the megafauna extinction, a black mat across the Northern hemisphere, nanodiamond... Deep troughs in Lake Superior support the hypothesis of Younger Dryas Boundary (YDB) comet impact 12,900 BP. The impact theory explains the megafauna extinction, a black mat across the Northern hemisphere, nanodiamonds, platinum and iridium, and the enigmatic Carolina Bays (CB). While the CB were thought to predate Clovis cultural remains, but this must now be seen as spurious as the CB occur on Long Island, an LGM terminal moraine & on end-glacial flood plains, according to Allen West. The CB sand rims are exceptionally pure quartz with large phenocrysts, and also they exude hydrogen (H). This suggests origin from deep granitic plutons, the granite typically being over-saturated with silica. When the Russian Kola Peninsula Superdeep Borehole had reached 40,000 ft, H was boiling from the borehole. This H is among volatiles copiously dissolved in the mantle, from the primitive solar nebula. The granite is from the Lake Superior Province. Lakes Superior, Michigan, Huron & Ontario have deep holes, reaching to below sea level. Bathymetry exhibits a ~145 km circular contour in Eastern L. Superior, where deep troughs occur, eroded in breccias infilling impact explosion cavities many kms deep, as much as 15 to 35 km, the comet fragments coming in from the NW, with the holes lined up along the trajectory. This was an oblique impact with an extremely low angle of incidence, so the ejected granite quartz sands ended up in the CB along the Eastern seaboard principally. 展开更多
关键词 YOUNGER Dryas COMET Hypothesis Great LAKES COMET Impact CAROLINA bays Quartz SANDS
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Physico-Chemical Pollution and Trophic State of Biétry Bay (EbriéLagoon, Abidjan, Ivory Coast)
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作者 Dan Eude Kpannieu Kouakou Norbert Kouadio +3 位作者 Ignace Christian M’Bra Coulibaly Nagnonta Hippolyte Lacina Coulibaly S. Ouffouet 《Journal of Materials Science and Chemical Engineering》 2022年第5期87-99,共13页
The analysis of data from the National Observation Network (RNO) of the water quality of the Ivorian Anti-Pollution Center (CIAPOL) relating to the physico-chemical quality and the trophic state of the lagoon bays of ... The analysis of data from the National Observation Network (RNO) of the water quality of the Ivorian Anti-Pollution Center (CIAPOL) relating to the physico-chemical quality and the trophic state of the lagoon bays of C&#244te d’Ivoire has allowed apprehending the degree of pollution of the bays of Biétry. This bay is heavily polluted, overall, there is a high salinity at depth between 22.5‰ and 27.5‰, a slightly basic character with a pH oscillating between 7.8 and 8.1 for surface waters and between 7, 6 and 7.8 for bottom waters. This is a very marked surface oxygenation between 100.94% and 114.72%;a slightly elevated temperature oscillating between 28.6&degC and 29&degC for surface waters and between 26.6&degC and 27.1&degC for bottom waters. This is high turbidity due to suspended solids and high nitrogen and phosphorus concentrations as well. As a result, these waters evolve towards a “mesotrophic” character according to the OECD (1982) and they are “eutrophic” according to Carlson (1977). This water is therefore impure according to the WHO concerning water intended for bathing activities. 展开更多
关键词 Bietry bays POLLUTION Ebrié Lagoon EUTROPHIC
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Studying of Deformation Processes by Two-Coordinate Laser Strainmeter
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作者 Grigory I. Dolgikh 《International Journal of Clean Coal and Energy》 2013年第2期21-23,共3页
The results of experimental data processing of a two-coordinate laser strainmeter are discussed. The two-coordinate laser strainmeter consists of two laser strainmeters which measuring shoulders are oriented along the... The results of experimental data processing of a two-coordinate laser strainmeter are discussed. The two-coordinate laser strainmeter consists of two laser strainmeters which measuring shoulders are oriented along the lines “North- South” and “West-East”. Measurement accuracy of the earth's crust microdisplacements of these devices makes 0 to1 nm. Working frequency range is from 0 to 1000 Hz. Processing experimental data the main attention is paid to high tides, natural oscillations of the Earth, natural oscillations of geoblocks, superficial sea waves. It is established that after separate earthquakes the natural oscillations of regional geoblocks are strongly excited. Besides, it is revealed that quasiperiodic fluctuations of crust in the range of periods from 1 to 12 min. are caused by atmospheric processes. Besides, it is revealed that quasiperiodic oscillations of the earth's crust in the range of periods from 1 to 12 minutes are caused by atmospheric processes. 展开更多
关键词 Two-coordinate LASER Strainmeter High Tides Earthquakes NATURAL OSCILLATIONS of the Earth NATURAL Os-cillations of Geoblocks NATURAL OSCILLATIONS of bays Superficial and Internal Sea Waves Quasiperiodic OSCILLATIONS
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Relationship between Dam Construction and Red Tide Occurrence in Small Bays and the Seto Inland Sea, Japan with Considerations from the Gulf of Mexico
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作者 Kunio Ueda 《Open Journal of Marine Science》 2013年第4期201-211,共11页
There are many papers on red tide occurrences and eutrophication. Here, we use these data to examine the relationship between dam construction and red tide occurrence in Kesennuma Bay, Dokai Bay and the small bays of ... There are many papers on red tide occurrences and eutrophication. Here, we use these data to examine the relationship between dam construction and red tide occurrence in Kesennuma Bay, Dokai Bay and the small bays of the Seto Inland Sea, Japan. Here, for the first time, differences in mechanisms of red tide occurrences in these small bays are demonstrated. Mud overflowing from dams likely induces red tides in these areas as the mud flows out from the mouth of the rivers, is carried along the coast by the longshore current, and then enters and is deposited into small bays. Red tide is considered to be induced by the accumulation of mud and siltation. From data on the locations and year of red tide occurrences in the Gulf of Mexico, the same mechanism as for the occurrence of red tide in small bays of Japanwas found to be applicable. 展开更多
关键词 Red TIDE SILTATION Dam Construction SMALL bays Seto INLAND Sea GULF of Mexico
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Study of aquatic chemical characteristic in some bays along the coastal region of Zhejiang Province 被引量:2
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作者 Wang Yuheng,Dong Henglin and Jiang Guochang The Second Institute of Oceanography,State Oceanic Administration ,Hangzhou,China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1990年第4期547-554,共8页
In this paper,the aquatic chemical characteristics in the Hangzhou Bay,Xiangshan Bay and Leqing Bay along the coastal region of Zhejiang Province are discussed . Results show that the seasonal variations of chemical e... In this paper,the aquatic chemical characteristics in the Hangzhou Bay,Xiangshan Bay and Leqing Bay along the coastal region of Zhejiang Province are discussed . Results show that the seasonal variations of chemical elements are obvious. The distribution of silicate in Hangzhou Bay and contents of dissolved oxygen and nutrient in the Xiangshan Bay are found to be unusual in winter. Correlations among the elements are complex. The content of nutrient in the Hangzhou Bay is higher than that in Xiangshan Bay and the content of nutrient in the Xiangshan Bay is higher than that in the Leqing Bay . The variation of the ratio of N/P is obvious. This reflects the aquatic chemical characteristics in the bay. Finally, this paper also discusses the reason why the aquatic chemical characteristics in the bays are unusual. 展开更多
关键词 Study of aquatic chemical characteristic in some bays along the coastal region of Zhejiang Province bay
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多介质模型在海湾突发性有机污染中的应用及案例分析 被引量:2
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作者 莫俊超 张海生 +2 位作者 薛斌 刘小涯 张海娜 《环境监测管理与技术》 2011年第4期58-63,共6页
为弥补海洋环境监测能力不足,利用受潮汐动力控制海湾中的多介质模型,预测突发性污染发生后海洋环境中污染物的浓度变化信息,并对突发性污染物的迁移转化进行了计算。模型中使用逸度方法和质量平衡算法,预测非挥发性有机物在水、沉积物... 为弥补海洋环境监测能力不足,利用受潮汐动力控制海湾中的多介质模型,预测突发性污染发生后海洋环境中污染物的浓度变化信息,并对突发性污染物的迁移转化进行了计算。模型中使用逸度方法和质量平衡算法,预测非挥发性有机物在水、沉积物和鱼中的浓度。在象山港的应用结果表明,该模型可较快速地给出污染物在不同介质中的浓度变化信息,为环境监测和管理提供帮助。 展开更多
关键词 多介质模型 突发性污染事故 有机污染物 海湾
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Bootstrap方法与Bays Bootstrap方法的比较 被引量:2
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作者 王丙参 魏艳华 戴宁 《统计与决策》 CSSCI 北大核心 2015年第20期70-73,共4页
文章比较研究了Bootstrap方法与Bays Bootstrap方法的理论基础及其改进,给出了两者的区别与联系,讨论了它们的优缺点,结合实例验证了前面结论,特别得出:Bays Bootstrap方法模拟稳定,但小偏差超过一定界限时,实际效果不好。
关键词 BOOTSTRAP方法 bays BOOTSTRAP方法 偏差 参数估计
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A methodology for assessing the urban supply of on-street delivery bays
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作者 Antonio Comi JoséLuis Moura Sara Ezquerro 《Green Energy and Intelligent Transportation》 2022年第3期63-72,共10页
The loading and unloading operations carried out by transport and logistics operators have a strong impact on city mobility if they are not performed correctly.If loading/unloading bays,i.e.,delivery bays(DB),are not ... The loading and unloading operations carried out by transport and logistics operators have a strong impact on city mobility if they are not performed correctly.If loading/unloading bays,i.e.,delivery bays(DB),are not available for freight vehicle operations,operators may opt to double park or park on the sidewalk where there is no strong enforcement of these laws,with significant impact on congestion.This paper proposes a methodology for verifying and designing the number of delivery bays needed for freight vehicles for not interfere with cars or pedestrians.The methodology consists of two stages:in the first stage,an initial estimation is made using queueing theory.Subsequently,in the second stage,using such tentative scenario,in order to take into account the system stochasticity involving different entities,a discrete event simulation is performed to more realistically verify and upgrade(if necessary)the number of delivery bays to obtain the expected outcomes.The methodology was applied in the inner area of Santander(Spain).The study area was subdivided into 29 zones where the methodology was applied individually.The results indicated that none of these zones currently have an optimal number of delivery bays to satisfy demand.In some zones,there is an excess of delivery bays,although in most of them,there is a deficit which can cause significant impacts on traffic.The method proposed can be an effective tool to be used by city planners for improving freight operations in urban areas limiting the negative impacts produced in terms of internal and external costs. 展开更多
关键词 Urban freight transportation On-street delivery bays Discrete event simulation City logistics Urban goods movements
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闽南沿海主要海湾和河口湿地上覆水营养盐分布特征 被引量:1
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作者 韩智献 仝川 +1 位作者 刘白贵 黄佳芳 《湿地科学与管理》 2020年第4期49-53,共5页
研究不同海湾和河口区上覆水营养盐特征,可为海湾和河口湿地的水质管理和湿地保护提供基础数据。2015年秋季在福建省南部选取泉州湾、九龙江口、东山旧镇湾等海湾和河口湿地,采集不同群落类型湿地的上覆水样,测定上覆水中氮、磷等主要... 研究不同海湾和河口区上覆水营养盐特征,可为海湾和河口湿地的水质管理和湿地保护提供基础数据。2015年秋季在福建省南部选取泉州湾、九龙江口、东山旧镇湾等海湾和河口湿地,采集不同群落类型湿地的上覆水样,测定上覆水中氮、磷等主要营养元素及其理化指标。结果表明:东山旧镇湾湿地上覆水营养盐浓度(3.17 mg/L)高于泉州湾湿地(2.23 mg/L)和九龙江河口湿地(2.69 mg/L),分别高出42.15%和17.84%。泉州湾湿地上覆水NH4+-N浓度(1.71 mg/L)显著高于东山旧镇湾(0.76 mg/L)、九龙江河口(0.65 mg/L)(P<0.05);东山旧镇湾(1.98 mg/L)、九龙江河口湿地(1.46 mg/L)上覆水NO3--N显著高于泉州湾(0.29 mg/L)(P<0.05);不同湿地上覆水PO43--P浓度无显著差异。6种植物群落上覆水营养盐浓度分析表明,不同植物群落覆水NO3--N浓度差异显著(P<0.05)、NH4+-N、PO43--P浓度差异不显著(P>0.05)。由于沿海人类活动及入海河流营养盐输入的影响,NH4+-N、NO3--N在不同海湾和河口分布差异显著(P<0.05),短叶茳芏和芦苇湿地上覆水比红树林湿地滞留更多的NO3--N。 展开更多
关键词 上覆水 营养盐 红树林 盐沼 海湾 河口 福建南部
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Characteristics of modern sedimentation in Qingdao bays
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作者 陈正新 Paul Huang +3 位作者 黄海燕 董贺平 李少泉 李春 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第3期683-696,共14页
With available survey data and 237surface sediment samples,the modern sedimentation in Qingdao bays is studied.The research result shows that the east area is shallower(16.4 m) than that in the west(45.8 m).The geogra... With available survey data and 237surface sediment samples,the modern sedimentation in Qingdao bays is studied.The research result shows that the east area is shallower(16.4 m) than that in the west(45.8 m).The geography was formed by a symmetric wave in a sequence of bank-offshore depression-platform-tidal channel-platform-offshore depression-foreshore from south to north.Flood sedimentary systems were formed from inlet of the Jiaozhou Bay in the west to the barrier bar in the east.Lateral sedimentation includes mainly tidal current ridges in two tidal channels.Gravel sandy sediments formed by wave lie in midland of from seashore to wave base.Dynamic functions are mainly tide and wave.Tidal current moves sediment in vertical and horizontal directions,sorting sediments and providing materials for coastwise beaches.The sources of sediment are mainly from eroded headland rocks.In general,grain sizes in this area from the inlet of the Jiaozhou Bay in the west(120°17') to the barrier bar outside in the east(120°35') are coarse-fine-coarse,forming gravel-gravelly sand(G-S),sand(S),gravel clay silt(G-YT),clay silt(YT),gravelly silty sand(G-TS),silty sand(TS),gravelly sandy silt(G-ST),and sandy silt(ST) in turn. 展开更多
关键词 Qingdao bays surface sediments tidal current ridges sedimentary dynamics
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Saco-Casco Bays Inundation Modeling of Five Winter Storms
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作者 Saswati Deb Huijie Xue Shivanesh Rao 《Journal of Shipping and Ocean Engineering》 2021年第2期53-63,共11页
Coastal inundation along the northeast coast of the United States is usually caused by strong winter storms(WS).However,the accurate prediction of coastal inundation due to the WS is challenging.Therefore,our study ai... Coastal inundation along the northeast coast of the United States is usually caused by strong winter storms(WS).However,the accurate prediction of coastal inundation due to the WS is challenging.Therefore,our study aims to develop a unique high-resolution modeling system to accurately predict the coastal inundation in the ungauged coastal areas of Saco-Casco Bays and map the flood risk zones to potential sea level rise due to these storms.Hindcasts of five classic WS in 2014-2015 were studied.The inundation models are based on FVCOM that uses unstructured grid to capture the minor to significant flooding near the shallow areas of the bays,harbor entrance and river banks.In this study,topography has been generated from the NOAA’s integrated dataset of Portland,ME 1/3 arc-second MHW digital elevation model.The model runs were driven by two different sets of meteorological(NECOFS WRF and NOAA’s NAM WRF)forcing to examine the effect of spatial resolution on the predicted inundation.The study reveals that among the five storm surge cases,WS-III produces a maximum surge of 0.7 m and WS-II cause a minimum surge of 0.3 m.In all scenarios,southward wind-driven coastal current flowing towards Biddeford Pool,Pine Point and Camp Ellis forms a small-scale eddy which causes significant inundation however strength of the current varies accordingly.Sensitivity experiments have been carried out using NECOFS WRF simulation products with varying parameters of marshland elevation and bottom friction to understand the influence of intertidal storage on the predicted flooding. 展开更多
关键词 Coastal inundation winter storms Saco-Casco bays FVCOM NECOFS WRF.
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大开间异型柱框架弹塑性工作性能研究 被引量:20
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作者 曹万林 王绍英 胡国振 《世界地震工程》 CSCD 2000年第1期40-46,共7页
通过试验研究,探讨了大开间异型柱框架的强度、刚度、破坏特征及弹塑性工作性能。
关键词 大开间 异型柱 框架 弹塑性 工作性能
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基于Box算法的无功优化配置 被引量:18
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作者 黄华 熊信艮 +1 位作者 吴耀武 黄亦军 《电力系统自动化》 EI CSCD 北大核心 2000年第20期32-36,共5页
Box算法是工程优化设计中一种重要的直接搜索算法 ,适用于无法给出目标函数显式数学表达式的优化问题求解。针对无功优化配置问题非线性、非连续性及目标函数与控制变量的隐式关系等特点 ,提出了基于 Box算法的无功优化配置模型及相应... Box算法是工程优化设计中一种重要的直接搜索算法 ,适用于无法给出目标函数显式数学表达式的优化问题求解。针对无功优化配置问题非线性、非连续性及目标函数与控制变量的隐式关系等特点 ,提出了基于 Box算法的无功优化配置模型及相应求解步骤 ,利用罚函数处理函数约束、重复迭代及采用贝斯—德拉姆洗牌与组合方法产生随机数均能改善收敛性。对 IEEE6,1 4和 30节点以及实际大规模系统的数字仿真结果表明 。 展开更多
关键词 Box算法 无功优化配置 数学模型 电力系统
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渤海地区^(210)Pb、^(137)Cs同位素测年的研究现状 被引量:24
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作者 王福 王宏 +3 位作者 李建芬 裴艳东 范昌福 商志文 《地质论评》 CAS CSCD 北大核心 2006年第2期244-250,共7页
近百年来环渤海地区的沉积作用是影响该区近现代地质环境变化的重要因素。本文收集了该区迄今公开发表的用于确定现代沉积速率的84组210Pb、137Cs柱状剖面(包括210Pb样柱52组,210Pb、137Cs样柱32组),其中海区39组,潮间带及沿海低地地区4... 近百年来环渤海地区的沉积作用是影响该区近现代地质环境变化的重要因素。本文收集了该区迄今公开发表的用于确定现代沉积速率的84组210Pb、137Cs柱状剖面(包括210Pb样柱52组,210Pb、137Cs样柱32组),其中海区39组,潮间带及沿海低地地区45组。环渤海地区的210Pb放射性活度的深度分布曲线主要表现为3种形式:理想指数衰变型、近等幅摆动型和海洋特殊动力事件影响型。根据由陆向海方向沉积速率的变化,可初步划分为沿岸低沉积速率带、开放潮坪高沉积速率带及海区低沉积速率区;区域性差异则表现为渤海湾开放潮坪区上部由北(蓟运河口)向南(老狼坨子)沉积速率表现为高—低—高,辽东湾从其西侧的锦州湾向东至辽河河口的开放潮坪地区,沉积速率递减,黄河三角洲地区及其附近海域属于间歇式快速沉积区,莱州湾西部为高速沉积区。 展开更多
关键词 环渤海海岸带及海区^210Pb、^137Cs现代沉积速率
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前期风场控制的太湖北部湖湾水动力及对蓝藻水华影响 被引量:26
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作者 吴挺峰 朱广伟 +2 位作者 秦伯强 丁艳青 吴善锋 《湖泊科学》 CAS CSCD 北大核心 2012年第3期409-415,共7页
为明确前期风场对太湖北部湖湾水动力及蓝藻水华分布的影响,对2008年9月梅梁湾及贡湖湾水文、水质及气象开展了同步观测,结果表明:受前期东北风影响,梅梁湾及贡湖湾表层、中层及底层湖流流向均顺风向自湾内流向湾外,两个湖湾均不存在补... 为明确前期风场对太湖北部湖湾水动力及蓝藻水华分布的影响,对2008年9月梅梁湾及贡湖湾水文、水质及气象开展了同步观测,结果表明:受前期东北风影响,梅梁湾及贡湖湾表层、中层及底层湖流流向均顺风向自湾内流向湾外,两个湖湾均不存在补偿流.表层湖流对风场变化响应敏感,而中场及底层流场对风场变化响应存在显著滞时.在偏南风作用下,梅梁湾表层湖流能快速形成顺时针环流.在偏西风作用下,贡湖湾表层湖流流向虽未发生偏转,但是湖流流速显著减小并导致流速沿水体垂向呈递增分布.观测期间水动力强度对太湖北部湖区叶绿素a浓度垂向分层及蓝藻水华水平漂移均具有重要影响.在水动力滞缓水域,蓝藻水华易在水表发生漂移堆积.在水动力强度较大水域,强烈的垂向混合作用能使蓝藻沿水深方向混合均匀,降低水华暴发风险.相对于水动力条件,营养盐对叶绿素a浓度空间分布的影响较弱. 展开更多
关键词 前期风场 太湖 北部湖湾 水动力 蓝藻水华
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