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Chinese Journal Of Geochemistry 2006年第B8期25卷 259-259页

作者： Qizhen liU jiufa li Gui FU Weichang LU Daoji li State Key Laboratory of estuarine and coastal research East China Normal University Shanghai 200062 China Department of Chemistry East China Normal University Shanghai 200062 China

Numerical prediction on the scour burial of cylinder object freely resting on the sandy seabed in the east china Sea using the DRAMBUIE model

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International Journal of Sediment research 2014年第4期29卷 509-517页

作者： Chong-guang PANG li-qian liU Kun li institute of Oceanology Chinese Academy of Sciences Key Laboratory of Ocean Circulation and Waves Chinese Academy of Sciences university of Chinese Academy of Sciences

After experiencing 8-day combined tidal current,circulation and wave actions,scour depth surrounding cylinder object freely resting on sandy seabed in the east china Sea(ECS) in January is numerically predicted using the DRAMBUIE model designed for scour burial,which has been widely used and verified by in-situ *** the period of numerical integration,the value of time t is generally variable at every time step via the special time-stepped approach developed by this paper to eliminate the time *** tidal current velocity,wave orbital velocity and the depth-averaged circulation in the ECS have been obtained by numerical simulations with estuarine coastal and Ocean Model(ECOM),Simulating Waves Nearshore(SWAN) model and Regional Ocean Modeling System(ROMS) model *** control experiment and several idealized test cases on influential factors in scour depth reveal that the dominant hydrodynamic factor is tidal current in the ECS under normal weather conditions,and the impacts of shelf circulation and wave motion on local scour almost can be ignored with an exception of the Kuroshio area where the high-speed mainstream of Kuroshio *** is also indicated that in sandy sediments,the distribution of scour depth nearly follows the pattern of tidal currents,while the secondary influencing factor on scour depth appears to be grain size of sandy sediment in the *** tests on sediment grain size further testify that much finer sand is more easily scoured,and an increasing trend for scour depth with reduction of grain size is displayed due to imposed resistance of larger sized *** aspects explored by this paper,including the empirical equations in the Defense research Agency Mine Burial Environment(DRAMBUIE) model,the accuracy of inputs and infill process can severely affect the prediction of scour depth surrounding cylinder objects freely resting on sandy seabed in the ECS.

关键词： Scour burial in sandy sediments Cylinder object Time-stepped fashion Numerical simulation The DRAMBUIE model The east china Sea

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人类活动对鄱阳湖水位变化的影响

水文 2020年第4期40卷 53-60页

作者：赵军凯李立现李九发赵瑞哲王辉刘新圣九江学院旅游与地理学院九江市土地测量与3S技术应用重点实验室(九江学院)江西九江332005 华东师范大学河口海岸学国家重点实验室上海200062 中国科学院信息工程研究所北京100080

进入21世纪以来,长江干流上游水库群运行和鄱阳湖区采砂等人类活动对鄱阳湖与长江之间水沙交换过程产生了重要影响,加速了江湖关系演变。主要采用Mann-Kendall趋势检验法和其他统计分析法,分析了近50年来鄱阳湖水位变化阶段性和趋势性特... 详细信息

进入21世纪以来,长江干流上游水库群运行和鄱阳湖区采砂等人类活动对鄱阳湖与长江之间水沙交换过程产生了重要影响,加速了江湖关系演变。主要采用Mann-Kendall趋势检验法和其他统计分析法,分析了近50年来鄱阳湖水位变化阶段性和趋势性特征,并探讨了长江干流上游水库群调节和湖区采砂活动对鄱阳湖水位变化的影响机制。结果显示:2000~2014年鄱阳湖水位分阶段降低,2006~2014年水位降至最低,比2000年前低了1.08m。2000年之后,鄱阳湖全年、汛期和枯季平均水位都有减少趋势,特别是10月份平均水位有非常显著的减少趋势;不同季节主湖区与入江水道水位变化趋势不一致。长江干流上游水库群调节对鄱阳湖水位影响存在时空差异,水库群蓄水期加剧了鄱阳湖水位下降的幅度。人工采砂活动对鄱阳湖水位的影响在枯季尤其是冬季影响更明显。合理调度长江干流上游水库群及湖区采砂活动对维护鄱阳湖和长江关系的健康维持具有重要意义。

关键词：水位变化趋势性水库群调节采砂活动鄱阳湖人类活动

台风对淤泥质潮滩冲淤影响研究——基于无人机测量与现场水动力观测

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华东师范大学学报（自然科学版） 2024年第4期 150-160页

作者：张新淼薛力铭史本伟张文祥李天佑彭彪彪李秀珍汪亚平华东师范大学河口海岸学国家重点实验室上海200241 自然资源部第一海洋研究所自然资源部海岸带科学与综合管理重点实验室山东青岛266061

台风等极端天气会使淤泥质潮滩发生数十厘米的冲淤变化.在全球变暖导致台风强度及频率增大的背景下,厘清台风影响下潮滩冲淤变化及其机制,对潮滩保护与生态系统完整性维持具有重要意义.本文借助基于运动恢复结构算法的无人机(unmanned a... 详细信息

台风等极端天气会使淤泥质潮滩发生数十厘米的冲淤变化.在全球变暖导致台风强度及频率增大的背景下,厘清台风影响下潮滩冲淤变化及其机制,对潮滩保护与生态系统完整性维持具有重要意义.本文借助基于运动恢复结构算法的无人机(unmanned aerial vehicle,UAV)摄影测量方法,于2021年7月“烟花”台风前后对崇明东滩典型样地进行滩面高程测量,并在盐沼-光滩过渡带现场采集水动力泥沙数据.结果表明:无人机摄影测量精度为4.1 cm;台风影响下光滩区域侵蚀、盐沼区域淤积,变幅达±32 cm.其原因是:台风影响下,光滩区域在天文大潮时波高及水深增大,达到波浪破碎条件后表层沉积物被侵蚀并被强潮流搬运;涨潮流携带悬浮泥沙进入盐沼后,因盐沼缓流消浪作用导致水体挟沙能力下降,泥沙在盐沼区域沉积.因此,盐沼-光滩过渡带呈现光滩区域侵蚀、盐沼区域沉积的冲淤分带性.本文将无人机摄影测量与同步水动力泥沙现场观测结合,为深刻认识台风事件对潮滩冲淤的影响提供了新视角.

关键词：台风无人机测量冲淤变化现场观测冲淤机制

Tree Planting:How Fast Can It Accelerate Post-fire Forest Restoration?——A Case Study in Northern Da Hinggan Mountains,china

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Chinese Geographical Science 2010年第6期20卷 481-490页

作者： li Xiuzhen HE Hong S WANG Xugao XIE Fuju HU Yuanman li Yuehui institute of Applied Ecology Chinese Academy of SciencesShenyang 110016China State Key Laboratory of estuarine and coastal research East China Normal UniversityShanghai 200062China School of Natural Resources University of Missouri-Columbia Columbia MO 65211- 72 70 USA

In 1987,a catastrophic fire burned over 1330000 ha in the densely forested area of the Da Hinggan Mountains in the northeastern *** the fire,intensive management including burned trunk harvesting and coniferous tree planting had been conducted to accelerate forest *** study the long term effect of these activities on forest recovery,we used a simulation modeling approach to study long-term(300 years) forest dynamics under current planting and natural regeneration *** indicate that under tree planting scenario in the severely burned area,the dominant species Dahurian larch(Larix gmelinii) can reach pre-fire level(60% of the area) within 20 years and the maximum abundance can reach nearly 90% within 100 *** under natural regeneration scenario,it needs about 250 years to reach its pre-fire *** the perspective of timber production,tree planting can bring twice as much timber volume as that under natural regeneration within 300 years,which is the average longevity of *** needs about 70 years to reach the timber volume of pre-fire level under the planting scenario,whereas it requires at least 250 years to reach the timber volume of pre-fire level under natural regeneration *** dominant species Asian White birch(Betula platyphylla) responded negatively to the planting of coniferous *** general,tree planting of coniferous species after fire can greatly accelerate forest restoration in terms of species abundance and target timber volume,with desirable ecological and economic returns.

关键词： tree planting natural regeneration post-fire forest restoration species abundance timber volume LANDIS model

Estimating submarine groundwater discharge at a subtropical river estuary along the Beibu Gulf,china

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Acta Oceanologica Sinica 2021年第9期40卷 13-22页

作者： Xilong Wang Kaijun Su Juan Du linwei li Yanling Lao Guizhen Ning li Bin Guangxi Key Laboratory of Marine Disaster in the Beibu Gulf Beibu Gulf UniversityQinzhou 535011China institute of Radiation Medicine Chinese Academy of Medical Sciences and Peking Union Medical CollegeTianjin 300192China Key Laboratory of coastal Science and Engineering Beibu Gulf UniversityQinzhou 535011China State Key Laboratory of estuarine and coastal research East China Normal UniversityShanghai 200241China research Centre for Eco-Environmental Engineering Dongguan University of TechnologyDongguan 523808China Qinzhou Key Laboratory of Land Resources Use and Monitor Beibu Gulf UniversityQinzhou 535011China

In certain regions,submarine groundwater discharge(SGD)into the ocean plays a significant role in coastal material fluxes and their biogeochemical cycle;therefore,the impact of SGD on the ecosystem cannot be *** this study,SGD was estimated using naturally occurring radium isotopes(^(223)Ra and ^(224)Ra)in a subtropical estuary along the Beibu Gulf,*** results showed that the Ra activities of submarine groundwater were approximately 10 times higher than those of surface *** assuming a steady state and using an Ra mass balance model,the SGD flux in May 2018 was estimated to be 5.98×10^(6) m^(3)/d and 3.60×10^(6) m^(3)/d based on 224Ra and 223Ra,*** the same time,the activities of Ra isotopes fluctuated within a tidal cycle;that is,a lower activity was observed at high tide and a higher activity was seen at low *** on these variations,the average tidal pumping fluxes of SGD were 1.15×10^(6) m^(3)/d and 2.44×10^(6) m^(3)/d with 224Ra and 223Ra,*** SGD accounts for 24%-51%of the total ***,tidal pumping is an important driving force of the SGD in the Dafengjiang River(DFJR)***,the SGD of the DFJR Estuary in the coastal zone contributes significantly to the seawater composition of the Beibu Gulf and the material exchange between land and sea.

关键词： radium isotopes submarine groundwater discharge balance model tidal pumping Dafengjiang River Estuary

Using quantile regression to analyze the stressor–response relationships between nutrient levels and algal biomass in three shallow lakes of the Lake Taihu Basin, china

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Chinese Science Bulletin 2014年第28期59卷 3621-3629页

作者： Xiaohua Chen Xiaoping li State Key Laboratory of estuarine and coastal research East China Normal University Water Environmental research institute Shanghai Academy of Environmental Sciences

Understanding the stressor–response relationship between nutrient levels and algal biomass is a prerequisite for the management of eutrophication in lakes. In this study, a quantile regression(QR) approach was used to interpret the stressor–response relationships between nutrient(e.g., phosphorus, nitrogen) concentrations and algal biomass as measured by chlorophyll-a(Chl-a) levels. QR results indicated that Lake Dianshan and Lake Changdang,which are both heavily eutrophicated, were P-limited *** contrast, Lake Kuilei, which has significantly lower nutrient levels and algal biomass than the other two lakes,was P- and N-limited. Moreover, in Lake Kuilei, N and P levels had significant interaction effects on the algal biomass at the upper quantiles(s [ 0.68). The degree to which the lakes were P-limited increased with rises in the mean total P concentration in the lakes. QR has many advantages over ordinary least squares regression for discriminating limiting factors and, in particular, allows us to estimate changes near the upper extremes of distributions associated with limiting factors. QR is adapted to more specialized risk management problems, such as early warnings of the risk of algal *** probable value-at-risk of harmful algal blooms for Lake Kuilei, Lake Dianshan and Lake Changdang is s = 0.76(Chl-a = 9 mg/m3), s = 0.87(Chl-a = 24 mg/m3) and s = 0.72(Chl-a = 35 mg/m3), respectively. Given the results of the stressor–response relationship analysis, we conclude that reductions in P input represent the most feasible and least costly approach for managing eutrophication in the shallow lakes of the Lake Taihu Basin. To control the magnitude and duration of algal blooms in shallow lakes,reductions in P and N inputs are required. The 95 % CI bounds of slopes indicated that the interactions of nonnutrient factors with nutrients had strong impacts on the algal biomass in lightly eutrophicated Lake Kuilei. It is suggested that, in addition to reductions in n

关键词：富营养化湖泊藻类生物量分位数回归营养水平应激反应太湖流域回归分析中国

Emergency control of Spartina alterniflora re-invasion with a chemical method in Chongming Dongtan,china

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Water Science and Engineering 2020年第1期13卷 24-33页

作者： Zhi-yuan Zhao Yuan Xu lin Yuan Wei li Xiao-jing Zhu li-quan Zhang State Key Laboratory of estuarine and coastal research East China Normal UniversityShanghai 200062China institute of Eco-Chongming East China Normal UniversityShanghai 200062China

The exotic species Spartina alterniflora(***)seriously threatens the stability and functioning of saltmarsh ecosystems in the Yangtze *** efforts have been undertaken to control this species,but subsequent re-invasion is frequent,presenting a significant barrier to *** complexity and high cost of integrated physical control programs has necessitated a shift in focus,leading to considerable attention being paid to the potential of herbicides to control *** find a strategy for emergency control of small and scattered patches of re-invading ***,an in situ field experiment using Gallant(Haloxyfop-R-methyl)herbicide was *** growth parameters of plant density and height were used to evaluate the control efficiency of different treatment dosages and times and sediment samples were taken for environmental toxicity *** results show the following:(1)the control efficacy of the maximum proposed application dose(2.70 g/m2)was 92%for continuous swards and 100%for small patches,while those of other dosages(0.45 g/m2,0.90 g/m2,and 1.35 g/m2)were lower than 40%;(2)the appropriate implementation time was July to August with 100%mortality resulting from a single application,while *** was shown to be capable of recovering rapidly after treatment in May;and(3)there were no significant differences in the community structure of meiofauna among the herbicide treatments and the control,and no herbicide residues were detected in sediment samples collected from treatment *** chemical control method was implemented in the shanghai Chongming Dongtan National Bird Nature Reserve(CDNR).The results of this study indicate that Gallant is an environmentally friendly herbicide with high efficiency,which can be adopted for emergency control of re-invading ***.

关键词： Spartina alterniflora Re-invasion Chemical control method Gallant Yangtze Estuary

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鄱阳湖水位变化趋势性对人类活动响应分析

江西师范大学学报（自然科学版） 2019年第5期43卷 532-544页

作者：赵军凯李立现李九发赵瑞哲刘新圣杨静草九江学院旅游与国土资源学院九江市土地测量与3S技术应用重点实验室江西九江332005 华东师范大学河口海岸学国家重点实验室上海200062 中国科学院信息工程研究所北京100080

进入21世纪以来,长江干流上游水库群的运行对鄱阳湖与长江之间物质和能量的交换过程产生了重要影响,鄱阳湖流域的秋旱现象逐渐严重,江湖关系加速演变.采用Mann-Kendall趋势检验法、R/S(Rescaled Range Analysis)分析法、变差系数C v和... 详细信息

进入21世纪以来,长江干流上游水库群的运行对鄱阳湖与长江之间物质和能量的交换过程产生了重要影响,鄱阳湖流域的秋旱现象逐渐严重,江湖关系加速演变.采用Mann-Kendall趋势检验法、R/S(Rescaled Range Analysis)分析法、变差系数C v和偏态系数C s等方法,分析了2000年以来鄱阳湖水位变化趋势性特征;分析了长江干流上游水库群调节和湖区采砂活动对鄱阳湖水位趋势性变化的影响.结果显示:2000—2014年鄱阳湖水位分阶段降低,2006—2014年水位降至最低,比2000年前低1.08 m.2000年后,鄱阳湖全年、汛期和枯季平均水位都有减少趋势,10月份平均水位有非常显著的减少趋势;不同季节主湖区与入江水道水位变化趋势性不一致;H值表明鄱阳湖冬季水位减少有较强的持续性.长江干流上游水库群调节对鄱阳湖水位影响存在时空差异,水库群蓄水期加剧了鄱阳湖水位下降的幅度,对湖心区影响达4%以上.采砂活动对鄱阳湖水位的影响在2006—2014年表现明显,除了10月份外其余季节的影响都大于长江干流上游水库群调节作用.合理调度长江干流上游水库群及湖区采砂活动在保护鄱阳湖生态环境中具有重要意义.

关键词：水位变化趋势性水库群调节采砂活动鄱阳湖长江

Biogenic silica concentration as a marine primary productivity proxy in the Holsteinsborg Dyb, West Greenland, during the last millennium

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Acta Oceanologica Sinica 2020年第9期39卷 78-85页

作者： Longbin Sha Dongling li Yanguang liu Bin Wu Yanni Wu Karen Luise Knudsen Zhongqiao li Hao Xu Department of Geography and Spatial Information Techniques Ningbo UniversityNingbo 315211China Laboratory for Marine Geology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China State Key Laboratory of estuarine and coastal research East China Normal UniversityShanghai 200062China Key Laboratory of Marine Sedimentology and Environmental Geology First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Key Laboratory of Marine Ecosystem and Biogeochemistry Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Centre for Past Climate Studies and Arctic research Centre Department of GeoscienceAarhus UniversityAarhus C DK-8000Denmark

We analyzed the biogenic silica(BSi)content and produced a diatom-based summer sea-surface temperature(SST)reconstruction for sediment core GC4 from the Holsteinsborg Dyb,West *** aim was to reconstruct marine productivity and climatic fluctuations during the last *** BSi content and diatom abundance suggest relatively high marine productively during the interval of AD 1000–1400,corresponding in time to the Medieval Warm Period(MWP).The summer SST reconstruction indicates relatively warm conditions during AD 900–1100,followed by cooling after AD *** extended cooling period during AD 1400–1900 is characterized by prolonged low in reconstructed SST and high sea-ice *** BSi values fluctuated during this period,suggesting varying marine productivity during the little Ice Age(liA).There is no significant correlation between the BSi content and SST during the last millennium,suggesting that the summer SST has little influence on marine productively in the Holsteinsborg Dyb.A good correspondence between the BSi content and the element Ti counts in core GC4 suggests that silicate-rich meltwater from the Greenland ice sheet was likely responsible for changes in marine productively in the Holsteinsborg Dyb.

关键词： biogenic silica marine productivity sea-surface temperature sea-ice concentration