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Regime shifts of hydrometeorological factors in the Jiaozhou Bay and their potential ecological impacts

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Chinese Journal Of Geochemistry 2013年第4期32卷 436-445页

作者： liu Zhe ZHANG Jing WEI Hao liu dongyan Key Laboratory of Marine Environment and Ecology(Ocean University of China) Ministry of Education State Key Laboratory of Estuarine and Coastal Research East China Normal University College of Marine Science and Engineering Tianjin University of Science and Technology Yantai Institute of Coastal Zone Research Chinese Academy of Sciences

The wavelet transform was applied to studying the regime shifts of hydrometeorological factors(i.e.,precipitation,air temperature,sea surface temperature and sea surface salinity)during the period of 1961–2000 in the Jiaozhou Bay(JZB).The results indicated clearly that these factors show variability of multiple timescales,with interannual and decadal periods.The local abrupt changes such as the 1978–1979 and 1988–1989 shifts feature the physical environment variation,which is consistent with the Southern Oscillation and Arctic Oscillation in the northern hemisphere.In regard to the JZB ecosystem,the benthic diatom cell abundance(BEN)showed a decrease shift in1978–1979,which is closely related to the precipitation abrupt decrease,while the shellfish mortality disaster in the JZB greatly released the predating pressure of diatom growth,possibly resulting in BEN increase shift in 1995.

关键词：水文气象要素胶州湾生态影响气象因素政权小波变换时间尺度物理环境

Macroalgae Blooms and their Effects on Seagrass Ecosystems

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Journal of Ocean University of China 2014年第5期13卷 791-798页

作者： HAN Qiuying liu dongyan Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation CAS Shandong Provincial Key Laboratory of Coastal Zone Environmental Processes CAS Experimental Station of Integrated Coastal Environment in Muping Yantai Institute of Coastal Zone Research (YIC) Chinese Academy of Sciences

Seagrass decline caused by the macroalgae blooms is becoming a common phenomenon throughout temperate and tropical regions. We summarized the incidence of macroalgae blooms throughout the world and their impact on seagrass beds by direct and indirect ways. The competition for living space and using resources is the most direct effect on seagrass beds when macroalgae are blooming in an aquatic ecosystem. The consequence of macroalgae blooms(e.g., light reduction, hypoxia, and decomposition) can produce significant indirect effects on seagrass beds. Light reduction by the macroalgae can decrease the growth and recruitment of seagrasses, and decomposition of macroalgae mats can increase the anoxic and eutrophic conditions, which can further constrict the seagrass growth. Meanwhile, the presence of seagrass shoots can provide substrate for the macroalgae blooms. Controlling nutrient sources from the land to coastal waters is a general efficient way for coastal management. Researching into the synergistical effect of climate change and anthropognic nutrient loads on the interaction between searsasses and macroalgae can provide valuable information to decrease the negative effects of macroalgae blooms on seagrasses in eutrophic areas.

关键词：水生生态系统藻类繁殖海草赤潮富营养化热带地区生活空间海岸管理

Chronological Link Between the Abrupt Change of the Loess Grain Size Sequence and the Formation of River Terraces on the Eastern Margin of the Qinghai-Tibetan Plateau Since the Late Early-Pleistocene

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Acta Geologica Sinica(English Edition) 2011年第3期85卷 723-732页

作者： liu dongyan QIAO Yansong LI Weiran XIE Ruihuang PENG Shasha College of Marine Geoscience Ocean University of China Qingdao 266100 China Key Laboratory of Submarine Science and Prospecting Techniques Ministry of Education Qingdao 266100 China Institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China College of Physical andEnvironmental Oceanography Ocean University of China Qingdao 266100 China Department of Meteorology University of Hawaii at Manoa Honolulu 96822 USA

Based on the study of magnetostratigraphy,magnetic susceptibility and grain size of Garze A section on the southeastern margin of the Qinghai-Tibetan Plateau since the late early-Pleistocene,the basal age of Garze loess is located at～1.16 MaBP and a series of abrupt paleoclimatic changes is detected.The times of abrupt changes are of distinct series features,and the interval between each two adjacent abrupt changes is～50 kyr or～100 kyr.The most significant abrupt changes occur at around 1.06,0.85,0.6,0.46,0.39 and 0.14 MaBP.There is a chronological link between the abrupt changes of paleoclimate and the formation of river terraces and it is almost simultaneous with a strengthening trend of neotectonic activities.Therefore,maybe the climatic transition controll the timing of terrace formation,and the tectonic uplift originate potential energy and has a direct effect on channel incision, both the climatic transition and the tectonic uplift are important.Terraces are the products of the interaction of instable climatic variations and tectonic uplift.Like the loess-paleosol sequences,river terrace sequences are also controlled by the climate-tectonic coupling system and are ruled by climate-tectonic gyration with a～100 kyr paracycle,which may be the short eccentricity period of the earth.

关键词： Garze loess grain size terrace tectonic uplift the Qinghai-Tibetan Plateau

CD93^(+)B淋巴细胞亚群在炎症及炎症相关疾病中的研究进展

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细胞与分子免疫学杂志 2024年第3期40卷 267-272页

作者：牛长平孙思予刘冬妍中国医科大学附属盛京医院实验研究中心辽宁沈阳110004 中国医科大学附属盛京医院辽宁省环境与代谢疾病动物模型研究与应用重点实验室辽宁沈阳110004

CD93表达于原B(pro-B)细胞、前B(pre-B)细胞以及各种不成熟B细胞,CD93可以和膜突蛋白(moesin)、多聚素2(MMRN2)等分子相互作用参与细胞迁移、黏附和吞噬过程,进而在炎症以及血管生成过程中发挥着重要的作用。检测CD93+B细胞亚群对炎症... 详细信息

CD93表达于原B(pro-B)细胞、前B(pre-B)细胞以及各种不成熟B细胞,CD93可以和膜突蛋白(moesin)、多聚素2(MMRN2)等分子相互作用参与细胞迁移、黏附和吞噬过程,进而在炎症以及血管生成过程中发挥着重要的作用。检测CD93+B细胞亚群对炎症及炎症相关疾病,如幽门螺杆菌相关性的胃炎、脓毒症、非肥胖型糖尿病以及牙周炎等疾病的诊断、治疗及预后监测具有重要的作用。

关键词： CD93 B淋巴细胞亚群胃炎脓毒症自身免疫性疾病综述

Radium-traced nutrient outwelling from the Subei Shoal to the Yellow Sea:Fluxes and environmental implication

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Acta Oceanologica Sinica 2022年第6期41卷 12-21页

作者： Jian’an liu dongyan liu Jinzhou Du State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200241China

The Subei Shoal is the largest sandy ridge in the southern Yellow Sea and is important source for nutrient loading to the sea.Here,the nutrient fluxes in the Subei Shoal associated with eddy diffusion and submarine groundwater discharge(SGD)were assessed to understand their impacts on the nutrient budget in the Yellow Sea.Based on the analysis of 223 Ra and 224 Ra in the field observation,the offshore eddy diffusivity mixing coefficient and SGD were estimated to be 2.3×10^(8)cm^(2)/s and 2.6×10^(9)m^(3)/d(16 cm/d),respectively,in the Subei Shoal.Combined the significant offshore decreasing gradients of nutrient in seawater of the Subei Shoal,the spatially integrated nutrient outwelling fluxes to the Yellow Sea were 262-1465μmol/(m^(2)·d)for DIN,5.2-21μmol/(m^(2)·d)for DIP and711-913μmol/(m^(2)·d)for DSi.Compared to the riverine input,atmospheric deposition and mariculture,nutrient outwelling from the Subei Shoal might play an important role in nutrient budget of the Yellow Sea.These nutrient fluxes could provide 4.1%-23%N and 1.3%-5.3%P requirements for the primary productivity,and the deviated DIN/DIP ratios have the potential to affect the growth of phytoplankton in the marine ecosystem of the Yellow Sea.

关键词： nutrient outwelling eddy diffusion submarine groundwater discharge radium isotopes Subei Shoal Yellow Sea

机织角联锁变密度复合材料的面外压缩力学特性

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纺织学报 2024年第7期45卷 63-71页

作者：王遵钦刘东炎王晓旭张典堂生态纺织教育部重点实验室(江南大学) 江苏无锡214122

为研究变密度结构设计对三维机织角联锁复合材料面外力学性能的影响,设计制备了三维机织角联锁不变密度复合材料、三维机织角联锁经纱变密度复合材料和三维机织角联锁纬纱变密度复合材料。结合扫描电子显微镜、数字图像相关技术和X射线... 详细信息

为研究变密度结构设计对三维机织角联锁复合材料面外力学性能的影响,设计制备了三维机织角联锁不变密度复合材料、三维机织角联锁经纱变密度复合材料和三维机织角联锁纬纱变密度复合材料。结合扫描电子显微镜、数字图像相关技术和X射线计算机断层扫描等检测技术,对角联锁变密度复合材料的面外压缩力学行为、内部损伤量化和渐进损伤等进行了测试与表征。研究结果表明:上疏下密角联锁纬纱变密度复合材料展现出优异的压缩性能,其压缩比强度比不变密度复合材料高3.40%;同时,上疏下密角联锁纬纱变密度复合材料损伤体积仅为11.64 mm 3,远低于不变密度复合材料的26.90 mm 3。进一步分析得到,不变密度复合材料压缩破坏以剪切失效为主,而上疏下密角联锁纬纱变密度复合材料则为基体开裂。

关键词：角联锁织物碳/环氧复合材料变密度结构设计面外压缩计算机断层扫描技术损伤机制

Analyzing biases of nitrogen contents and δ^(15)N values arising from acidified marine sediments with different CaCO_3 concentrations

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Acta Oceanologica Sinica 2018年第8期37卷 1-5页

作者： PENG Yajun liu dongyan WANG Yujue RICHARD Pierre KEESING John K. Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone Research Chinese Academy of Sciences School of Management Science Guizhou University of Finance and Economics State Key Laboratory of Estuarine and Coastal Research East China Normal University Littoral Environment et Sociétés UMR 7266 CNRS-Université de La Rochelle CSIRO Oceans and Atmosphere and University of Western Australia Oceans Institute Indian Ocean Marine Research Centre

In some studies, the researchers pretreated and measured organic carbon, nitrogen and their isotopes（δ^（13）C and δ^（15）N） of marine sediment together, to save costs and resources of analysis. However, the procedure of acidification to remove inorganic carbon for analysing δ^（13）C can affect the values of nitrogen and δ^（15）N, and the biases vary a lot depending on the CaCO_3 contents of sediments. In this study, the biases of total nitrogen（TN）and δ^（15）N values arising from acidified sediments were compared between the CaCO_3-poor（1%–16%） and CaCO_3-rich（20%–40%） samples. TN and δ^（15）N values were altered during acid treatment（without centrifugation） that possibly led to N-containing compounds volatilization. For CaCO_3-poor samples, acidification led to a range of 0%–40% TN losses and 0‰–2‰ shift in δ^（15）N values; and 10%–60% TN losses and 1‰–14‰ shift in δ^（15）N values for CaCO_3-rich samples. The biases from most samples exceeded the precision of the instrument（0.002% for TN and 0.08‰ for δ^（15）N）, and high biases could mislead our judgment for the environmental implication of the data. Thus,avoiding co-analysis of organic carbon, nitrogen and their isotopes（δ^（13）C and δ^（15）N） in sediments, even for CaCO_3-poor marine sediments, is necessary.

关键词： stable isotope nitrogen nitrogen CaCO3 acidification marine sediment

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中国四个河口潮间带甲藻孢囊多样性研究

海洋科学 2024年第4期48卷 30-44页

作者：罗芳王玉珏石雅君韩秋影顾海峰刘东艳华东师范大学河口海岸学国家重点实验室上海200062 中国科学院烟台海岸带研究所山东烟台264003 海南热带海洋学院海南三亚572022 自然资源部第三海洋研究所福建厦门361005

2014—2016年,为调查研究中国大辽河、涧河、闽江与九龙江河口潮间带表层沉积物中甲藻孢囊多样性,开展了4个季度表层沉积物样品采集,通过多钨酸钠法提取甲藻孢囊后进行鉴定,共鉴定出43种(隶属16属)和5种未定种,包括自养型17种和异养型2... 详细信息

2014—2016年,为调查研究中国大辽河、涧河、闽江与九龙江河口潮间带表层沉积物中甲藻孢囊多样性,开展了4个季度表层沉积物样品采集,通过多钨酸钠法提取甲藻孢囊后进行鉴定,共鉴定出43种(隶属16属)和5种未定种,包括自养型17种和异养型26种。其中孟迪原多甲藻(Protoperidinium mendiolae),脆弱海胆藻(Echinidinium delicatum)和透明海胆藻(E.transparantum)为我国沿海未报道的新记录种类。调查中发现了一种产麻痹性贝毒的塔玛亚历山大藻复合体(Alexandrium tamarense com-plex),以及3种产虾夷扇贝毒素的甲藻孢囊,分别为网纹原角藻(Protoceratium reticulatum),多边舌甲藻(Lingulodinium polyedrum)和具刺膝沟藻(Gonyaulax spinifera)。甲藻孢囊丰度在4个河口的分布具有明显差异。大辽河口孢囊丰度最高,变化范围为47~94 cysts/g DW(干质量);其次为涧河口,孢囊丰度变化范围为24~75 cysts/g DW;闽江口与九龙江口孢囊丰度相对较低,变化范围分别为14~50 cysts/g DW与5~50 cysts/g DW。与沉积物环境因素的相关性分析表明,自养型孢囊丰度和孢囊总丰度均与河口盐度、间隙水总溶解态氮营养盐浓度、溶解无机氮浓度、氨氮浓度呈显著正相关关系;多样性指数与盐度、沉积物粒度(<63μm)呈显著正相关关系。该研究对于了解我国河口潮间带甲藻孢囊多样性以及形成机制具有重要参考价值。

关键词：河口潮间带甲藻孢囊多样性环境因子

Predicting carbon storage of mixed broadleaf forests based on the finite mixture model incorporating stand factors,site quality,and aridity index

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Forest Ecosystems 2024年第3期11卷 276-286页

作者： Yanlin Wang Dongzhi Wang dongyan Zhang Qiang liu Yongning Li College of Forestry Hebei Agricultural UniversityBaoding071001China College of Economics and Management Hebei Agricultural UniversityBaoding071001China

The diameter distribution function(DDF)is a crucial tool for accurately predicting stand carbon storage(CS).The current key issue,however,is how to construct a high-precision DDF based on stand factors,site quality,and aridity index to predict stand CS in multi-species mixed forests with complex structures.This study used data from70 survey plots for mixed broadleaf Populus davidiana and Betula platyphylla forests in the Mulan Rangeland State Forest,Hebei Province,China,to construct the DDF based on maximum likelihood estimation and finite mixture model(FMM).Ordinary least squares(OLS),linear seemingly unrelated regression(LSUR),and back propagation neural network(BPNN)were used to investigate the influences of stand factors,site quality,and aridity index on the shape and scale parameters of DDF and predicted stand CS of mixed broadleaf forests.The results showed that FMM accurately described the stand-level diameter distribution of the mixed P.davidiana and B.platyphylla forests;whereas the Weibull function constructed by MLE was more accurate in describing species-level diameter distribution.The combined variable of quadratic mean diameter(Dq),stand basal area(BA),and site quality improved the accuracy of the shape parameter models of FMM;the combined variable of Dq,BA,and De Martonne aridity index improved the accuracy of the scale parameter models.Compared to OLS and LSUR,the BPNN had higher accuracy in the re-parameterization process of FMM.OLS,LSUR,and BPNN overestimated the CS of P.davidiana but underestimated the CS of B.platyphylla in the large diameter classes(DBH≥18 cm).BPNN accurately estimated stand-and species-level CS,but it was more suitable for estimating stand-level CS compared to species-level CS,thereby providing a scientific basis for the optimization of stand structure and assessment of carbon sequestration capacity in mixed broadleaf forests.

关键词： Weibull function Finite mixture model Linear seemingly unrelated regression Back propagation neural network Carbon storage