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Revisit the K-segment of the Southeast Indian Ridge for new evidence of hydrothermal plumes

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Chinese Science Bulletin 2011年第33期56卷 3605-3609页

作者： WANG TingTing chen yongshun john TAO ChunHui Institute of Theoretical and Applied Geophysics School of Earth and Space Sciences Peking University Beijing 100871 China The Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China

在到在 2007 的东南印度理兹(SEIR ) 的中国研究巡航的第一条腿期间，我们重游 SEIR 的 K 片断并且在一个 CTD 演员组车站观察了一个水列混浊异例。这个车站被定位从一个羽毛异例上的一个捞网地点的 400 m 由美国科学家在 1996 检测了... 详细信息

在到在 2007 的东南印度理兹(SEIR ) 的中国研究巡航的第一条腿期间，我们重游 SEIR 的 K 片断并且在一个 CTD 演员组车站观察了一个水列混浊异例。这个车站被定位从一个羽毛异例上的一个捞网地点的 400 m 由美国科学家在 1996 检测了。在我们的调查检测的混浊异例的特征与那些不同以前观察了 11 年，暗示也，检测异例有不同、不同的羽毛来源或羽毛的坚韧性在干涉时间变化了。另外，混浊异例在深 tow-yo 侧面在 K 片断上在二个地区被观察。如果这二个异例没被连接，计算的羽毛发生将是大约 0.28，比为传播的 65 mm/a 的 0.25 的预言的价值大率。K 片断上的羽毛发生的这增加似乎与圣保拉姆斯特达姆热点的影响有关，定位了大约 300 km 到西北。

关键词：南印度洋东南亚证据热液美国科学家阿姆斯特丹发病率异常

Stable hydrogen isoscape in precipitation generated using data fusion for East China

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Science China Earth Sciences 2024年第9期67卷 2972-2988页

作者： Jiacheng chen Jie chen Xunchang john ZHANG Peiyi PENG State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan 430072China Hubei Key Laboratory of Water System Science for Sponge City Construction Wuhan UniversityWuhan 430072China USDA-ARS Oklahoma and Central Plains Agricultural Research Center El Reno OK 73036USA Southwest Research Institute for Hydraulic and Water Transport Engineering Chongqing Jiaotong UniversityChongqing 400016China

The stable hydrogen isotope in precipitation is an effective environmental tracer for climatic and hydrologic ***,accurate and high-precision precipitation hydrogen isoscapes are currently unavailable in *** this study,a data fusion method based on Convolutional Neural Networks(CNN)is used to fuse the hydrogen isotopic composition(δ^(2)H_(p))of observations and isotope-equipped general circulation model(iGCM)simulations.A precipitation hydrogen isoscape with a temporal resolution of monthly and a spatial resolution of 50-60 km is established for East China for the 1969-2017 *** to building the isoscape,the performance of three data fusion methods(DFMs)and two bias correction methods(BCMs)is *** results indicate that the CNN fusion method performs the best with a correlation coefficient larger than 0.90 and root mean square error smaller than 10.5‰ when using observation as a *** fusion methods based on back propagation and long short-term memory neural network perform similarly,while slightly outperforming the bias correction ***,the CNN method is used to generate the hydrogen isoscape,and the temporal and spatial distribution characteristics of the hydrogen isotope in precipitation are analyzed based on this *** generated isoscape shows similar spatial and temporal distribution characteristics to *** general,the distribution pattern of δ^(2)H_(p) is consistent with the temperature effect in northern China,and consistent with the precipitation amount effect in southern *** trend of the δ^(2)H_(p) time series is consistent with that of observed precipitation and ***,the generated isoscape effectively reproduces the observations,and has the characteristics of time continuity and relative spatial regularity,which can provide valuable data support for tracking atmospheric and hydrological processes.

关键词： Precipitation Precipitation isotope General circulation model Data fusion Dataset

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黑龙江地区背景噪声面波群速度层析成像

地球物理学报 2011年第4期54卷 1043-1051页

作者：高东辉陈永顺孟宪森张永刚唐有彩北京大学地球与空间科学学院理论与应用地球物理研究所北京100871 黑龙江省地震局哈尔滨150090

本文选取黑龙江省台网及吉林、内蒙古部分台站共44个固定地震台站连续2年的地震数据,利用两个台站间互相关方法获得瑞利面波经验格林函数,再用自适应时频分析方法提取群速度频散曲线,最后利用传统面波层析成像方法反演获得黑龙江地区周... 详细信息

本文选取黑龙江省台网及吉林、内蒙古部分台站共44个固定地震台站连续2年的地震数据,利用两个台站间互相关方法获得瑞利面波经验格林函数,再用自适应时频分析方法提取群速度频散曲线,最后利用传统面波层析成像方法反演获得黑龙江地区周期为8～40s范围内群速度分布图像.反演结果揭示黑龙江地区地壳及上地幔群速度结构存在明显横向不均匀性.短周期群速度异常与研究区内山脉、盆地和断层带的分布有较好的对应关系:8～20s群速度显著低速异常显示松辽盆地具有较厚的沉积层.周期为16～25s的高、低速度异常区的反转反映了大兴安岭地区莫霍面深度大于松辽盆地.周期为30～40s群速度分布图像较好地体现深部构造与浅部构造的对应关系,尤其是观测到了依兰一伊通断裂带以东区域可能反映上地幔物质活动的低速异常.本研究也为进一步结合传统天然地震面波成像方法,获取该区域地壳和上地幔三维剪切波速度结构奠定基础,对研究东北地区构造活动以及探讨深源地震分布和成因具有重要科学意义.

关键词：背景噪声互相关格林函数群速度频散面波层析成像黑龙江地区

基于背景噪声反演华南块体岩石圈三维S波速度结构

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北京大学学报（自然科学版） 2024年第3期60卷 442-452页

作者：吕杰陈永顺郭震北京大学地球与空间科学学院北京100871 南方科技大学海洋科学与工程系深圳518055

利用背景噪声方法,对布设在华南块体及其周边区域数个流动地震台阵中共704个地震台站的连续数据进行分析,反演得到华南岩石圈的三维S波速度结构。结果表明,地表附近S波速度结构与华南块体的地表构造高度相关,低速异常区集中在四川盆地... 详细信息

利用背景噪声方法,对布设在华南块体及其周边区域数个流动地震台阵中共704个地震台站的连续数据进行分析,反演得到华南岩石圈的三维S波速度结构。结果表明,地表附近S波速度结构与华南块体的地表构造高度相关,低速异常区集中在四川盆地和江汉盆地等沉积层较厚的区域。江南造山带的中上地壳呈现明显的高速异常,该高速异常即为华夏块体与扬子块体的分界区域。华夏块体中地壳低速异常区与该区域广泛分布的中生代花岗岩对应较好。华南上地幔岩石圈的东部与西部存在显著的速度差异,西部呈现显著的高速异常,反映西部四川盆地底部稳固的克拉通结构;上地幔的低速异常揭示华南东部岩石圈因太平洋板块俯冲的影响而明显减薄(<70km)。推测华夏块体以琼州海峡为中心的上地幔显著低速区可能对应海南地幔柱的热物质上涌。

关键词：华南块体 S波速度结构江南造山带板块俯冲

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新疆地区环境噪声层析成像研究

地球物理学报 2011年第8期54卷 2042-2049页

作者：唐小勇范文渊冯永革唐有彩陈永顺朱丽霞北京大学地球与空间科学学院理论与应用地球物理研究所北京100871 重庆市地震局重庆401147

本文利用北京大学宽频带流动地震台阵和新疆地震监测台网12个月连续地震记录数据,采用环境噪声层析成像方法获得了新疆地区的周期从10～35 s范围内的瑞利面波相速度异常分布图像.研究结果与地表地质构造相一致,新疆地区的天山、两盆大... 详细信息

本文利用北京大学宽频带流动地震台阵和新疆地震监测台网12个月连续地震记录数据,采用环境噪声层析成像方法获得了新疆地区的周期从10～35 s范围内的瑞利面波相速度异常分布图像.研究结果与地表地质构造相一致,新疆地区的天山、两盆大地构造与瑞利面波相速度异常有较好的对应关系.短周期10～20 s的图像显示两个盆地内都呈现低速异常,对应盆地较厚的沉积层.中长周期25～35 s的层析成像结果显示东西天山地区存在明显异常差异.本文获得的新疆地区地壳和上地幔相速度结果,也为进一步结合传统天然地震面波成像方法,最终获得新疆地区的三维剪切波速度结构奠定基础.

关键词：新疆 Rayleigh面波环境噪声层析成像

Adaptive strategies of high and low nucleic acid prokaryotes in response to declining resource availability and selective grazing by protozoa

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Science China Earth Sciences 2024年第6期67卷 1872-1884页

作者： chen HU Liuqian YU Xiaowei chen Jihua LIU Yao ZHANG john BATT Xilin XIAO Qiang SHI Rui ZHANG Tingwei LUO Nianzhi JIAO Dapeng XU College of the Environment and Ecology Xiamen UniversityXiamen 361102China State Key Laboratory of Marine Environmental Science College of Ocean and Earth SciencesFujian Key Laboratory of Marine Carbon SequestrationXiamen UniversityXiamen 361102China Joint Lab for Ocean Research and Education(LORE)of Dalhousie University Canadaand Shandong University and Xiamen UniversityXiamen 361102China Earth Ocean and Atmospheric Sciences ThrustThe Hong Kong University of Science and Technology(Guangzhou)Guangzhou 510000China Institute of Marine Science and Technology Shandong UniversityQingdao 266237China Department of Oceanography Dalhousie UniversityHalifaxNova Scotia B3H 4R2Canada Institute for Advanced Study Shenzhen UniversityShenzhen 518060China Carbon Neutral Innovation Research Center Xiamen UniversityXiamen 361102China

Prokaryotes play a fundamental role in global ocean biogeochemical ***,how the abundance and metabolic activity of ecologically distinct subgroups(i.e.,high nucleic acid(HNA)and low nucleic acid(LNA)cells),and their regulating factors,change in response to changing marine environmental conditions remains poorly ***,we delved into the time-evolving dynamic responses of the HNA and LNA prokaryotic subgroups to declining resource availability and selective grazing by protozoa by conducting a 73-day incubation experiment in a large-volume(117,000 L)macrocosm that facilitates community-level *** found that the metabolic activity of the HNA subgroup was higher than that of the LNA subgroup when the macrocosm was resource replete but that the HNA subgroup declined more rapidly than the LNA subgroup as the resources became increasingly scarce,leading to a steadily increasing contribution of LNA cells to prokaryotic ***,as resources in the macrocosm became limited,protozoan grazing preference shifted from the HNA to the LNA subgroup and the contributions of the LNA subgroup to the carbon flow within the macrocosm *** findings highlight the resilience of LNA cells in resource-limited environments,illuminate the critical role of selective grazing by protozoa in balancing distinct prokaryotic subgroups under changing resource conditions,and demonstrate the complex and adaptive interactions between protozoa and prokaryotes across diverse environmental contexts.

关键词： Microbial loop Macrocosm experiment Prokaryote Top-down and bottom-up controls Carbon flow

Effect of cinnamaldehyde on Rhizopus stolonifer and on the conservation of sweet potato

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Food Quality and Safety 2024年第1期8卷 212-225页

作者：陈晨薛智超 Penta Pristijono john B.Golding 陈刚李永新杨虎清 College of Food and Health Zhejiang A&F UniversityHangzhouChina Zhejiang Provincial Key Laboratory of Resources Protection and Innovation of Traditional Chinese Medicine Zhejiang A&F UniversityHangzhouChina School of Environmental and Life Sciences University of NewcastleOurimbahNSWAustralia NSW Department of Primary Industries OurimbahNSWAustralia

Objectives:Rhizopus stolonifer,which causes soft rot of sweet potato,has resulted in substantial loss of economy *** and Methods:The antifungal effect and mechanism of cinnamaldehyde(CIN)against *** were explored by biochemical analysis and RNA-sequencing in this research,and the edible quality of CIN-treated sweet potato was ***:The results showed that CIN inhibited the growth of *** and reduced the incidence of soft rot in sweet potato at a minimum inhibitory concentration of 1000μL/*** damage of the cell walls of *** by CIN was associated with the upregulation of *** leakage and malondialdehyde content increased following CIN-treatment,which was correlated with increased reactive oxygen species levels and decreased catalase *** of ERG genes and oxidative stress-related genes following CIN treatment was associated with impaired cell membrane *** mitochondrial structure of *** was damaged by CIN treatment resulting in decreased respiration rates and ATP production,which was correlated with lower expression levels of IDH1,COX4,and ***:Our research suggests that the inhibition of CIN on *** was related to the disruption of its normal gene expression network,and CIN maintained the nutritional and edible quality of sweet *** study provides valuable insights into the antifungal mechanism of CIN on *** and the maintenance of root quality,which contributes to the effcient use of CIN for controlling soft rot in sweet potato.

关键词： Ipomoea batatas soft rot cinnamaldehyde antifungal mechanism transcriptome

Extractable and kerogen-bound hopanoids from typical Eocene oil shales in China

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Energy Geoscience 2024年第2期5卷 171-179页

作者： Changbo Zhai Zhirong Zhang john K.Volkman Hong Lu Yan'e chen SINOPEC Key Laboratory of Petroleum Accumulation Mechanisms Wuxi Institute of Petroleum GeologySINOPEC2060 Lihu RoadWuxiJiangsu213126China SINOPEC Petroleum Exploration and Production Research Institute 31 Xueyuan RoadBeijing100083China State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of ScienceGuangzhou510640GuangdongChina

This study conducted a comparative analysis of extractable hopanoid hydrocarbons and those released via stepwise pyrolysis of typical Eocene immature oil shales in China,namely the Huadian,Maoming,and Fushun *** the Huadian and Maoming shales exhibit immature indicators in extractable and kerogen-bound hopanoids(notably,high abundance of C_(29)to C_(32)17β,21β-hopanes and unsaturated hopenes).In contrast,the Fushun oil shale's hopanoids from extracts and pyrolyzates suggest a higher maturity *** absence of neohopenes in the pyrolyzates of the shales underpins that the kerogenbound hopanoid skeletons resist ***,the Huadian oil shale's asymmetric distribution of C_(29)and C_(30)hopenes and neohopenes hints at the presence of an additional *** unsaturated hopenes,such as hop-20(21)-enes,identified in pyrolyzates of the three kerogens at various pyrolysis temperatures,reveal the occurrence of double bonds in kerogen-bound hopanoid skeletons without methyl *** absence of hop-20-(21)-ene in extracts suggests that it might act as an intermediate of these novel hopenes during the epimerization of hopanoid skeletons within *** extractable and pyrolytic hopanoids'stereochemical alignment indicates that epimerization may occur in both ring systems and alkyl side chains of kerogen-bound hopanoid *** stepwise pyrolysis proves to be a quick screening method for geological hopanoids without causing any significant alteration to the original skeletons even when cracking multiple covalent bonds is necessary.

关键词： Hopanoid Hopane Hopene Neohopene Stepwise pyrolysis Kerogen Eocene oil shale

A four-band index for both liquid and solid water and its applications in the Aral Sea Basin

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Science China Earth Sciences 2024年第3期67卷 769-788页

作者： Bing YUE Xi chen Saibo LI Zhengping DU john WILSON Junhui YANG Yimen JIAO Shuangyan HUANG chenghu ZHOU Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Institute of Geographical Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Spatial Sciences Institute University of Southern CaliforniaLos AngelesCA 90089-0374USA

Various investigations have been conducted to analyze the water-coverage area of the Aral Sea and the Aral Sea Basin(ASB). However, the investigations incorporated considerable uncertainty and the used water indices had misclassification problem, which made different research groups present different results. Thus we first ascertain the boundaries of the ASB, the Syr and Amu river basins as well as their upper, middle and lower reaches. Then a four-band index for both liquid and solid water(ILSW) is proposed to address the misclassification problems of the classic water indices. ILSW is calculated by using the reflectance values of the green, red, near infrared, and thermal infrared bands, which combines the normalized difference water index(NDWI) and land surface temperature(LST) together. Validation results show that the ILSW water index has the highest accuracy by far in the Aral Sea Basin. Our results indicate that annual average decline of the water-coverage area was 963 km^(2) in the southern Aral Sea, whereas the northern Aral Sea has experienced little change. In the meanwhile, permanent ice and snow in upper reach of ASB has retreated considerably. Annual retreating rates of the permanent ice and snow were respectively 6233and 3841 km^(2) in upper reaches of Amu river basin(UARB) and Syr river basin(USRB). One of major reasons is that climate has become warmer in ASB. The climate change has caused serious water deficit problem. The water deficit had an increasing trend since the 1990s and its increasing rates was 3.778 billion m^(3) yearly on average. The total water deficit was 76.967 billion m^(3) on average in the whole area of ASB in the 2010s. However, up reaches of Syr river basin(USRB), a component area of ASB, had water surplus of 25.461 billion m^(3). These conclusions are useful for setting out a sustainable development strategy in ASB.

关键词： Aral Sea Basin Syr river basin Amu river basin Water indices Water-coverage area Water deficit Climate change