Hydraulic redistribution in the Inner Mongolia Huangfuchuan basins under different climate scenarios     

Kun Wang  Xia Xu  Qiong Gao 《Frontiers of Earth Science》2010,4(3):269-276

This paper describes the scaling up to a day scale of the Ryel hour scale model incorporating the process of hydraulic redistribution (HR). The Ryel model was applied to the Inner Mongolia Huangfuchuan basins to analyze transpiration, evaporation and stomatal conductance of Artemisia tridentate, and to indicate the added value of the feedback by comparing simulations with and without incorporating HR. Five climate scenarios were designed based on 40-y continuous climate data from the study area and the response of HR to the different climate scenarios was modeled. Under 1991 climate conditions, cumulative transpiration and evaporation with HR during the growing season were 161.7 mm and 206.14 mm, respectively, compared with transpiration of 140.7 mm and evaporation of 174.2 mm without HR. Under the five different climate change scenarios, HR influenced evaporation more than transpiration. The effect of HR on transpiration, evaporation and stomatal conductance was very different among the scenarios. Inclusion of HR gave rise to the largest increase in transpiration and evaporation under the T2P0 scenario and the smallest under the T2P2 scenario, but transpiration and evaporation decreased under the T0P-2 scenario. Stomatal conductance significantly increased with the inclusion of HR. The model used in this study has potential benefits for incorporating HR into soil processes, such as water movement and mass transfer.  相似文献   

基于多尺度有限元的海上升压站脚靴式桩套筒连接结构分析研究     

张伟  张坤  姜贞强  孙震洲  王永发  吕国儿  陈杰峰 《海洋工程》2022,40(2):55-66

脚靴式海上升压站导管架的桩套筒与主导管的连接结构是关键荷载传递部位。整体梁系有限元模型无法反应局部板型结构的失效状态;截断板系有限元模型则受制于边界条件的合理性,结果不够精确。文中基于某工程海上升压站,建立不同精细化范围的多尺度有限元模型及不同边界条件的截断模型,对结构屈服失效及屈曲失效复核的同时论证了局部网格对计算精细程度的影响及截断模型对边界条件的敏感性;此外,研究了轭板板厚及应力比对屈曲失效的敏感程度,为今后海上升压站脚靴结构不同阶段的设计、优化提供参考和借鉴。  相似文献   

渤海湾渔业碳汇分析与预测初探     

陈燕珊  万萌萌  林锟  于贞贞  王睿  谭丽菊  王江涛 《海洋科学》2022,46(9):77-84

为了解渤海湾近十年来渔业碳汇能力,本研究汇总了渤海湾地区2010-2020年海水养殖的品种和产量。通过建立不同养殖品种固碳能力评估体系,计算了不同养殖品种对渔业碳汇的贡献和渤海湾近十年海水养殖固碳总量。结果表明,2010-2020年渤海湾海水养殖以池塘养殖为主要养殖模式,年固碳量从2010年的5.79万吨增至2020年的11.04万吨,十年内共计固碳96.0万吨,平均碳转化比为12.5%,其中山东省贡献超过65%。该探索对建立“渔业碳汇”计算的指标体系、科学发展碳汇渔业、提升海洋碳汇生态价值具有一定的指导意义。  相似文献   

Study of frequency domain full waveform inversion based on Huber norm and L-BFGS algorithm     

WEI Yajie  HAN Liguo  DUAN Chaoran  WANG Hongye  GUO Kun 《世界地质(英文版)》2014,17(4):238-242

Full waveform inversion( FWI)is a high resolution inversion method,which can reveal detailed in-formation of the structure and lithology under comPlex geological background. It is limited by many kinds...  相似文献   

渤海表层悬沙的时空分布特征及其动力成因          下载免费PDF全文

庞重光  李坤  于炜 《海洋科学进展》2014,32(4)

针对目前渤海整个海域悬浮泥沙分布全貌的研究不充分。根据2000—2004年渤海表层悬浮泥沙分布特征选取7个典型海区,通过利用长时间序列悬沙质量浓度和风场遥感反演资料,在分析悬沙质量浓度与局地风速、物质来源等关系的基础上,定量研究风浪和潮流共同作用下、随季节显著变化的沉积物再悬浮过程,从而揭示整个渤海海域代表性海区悬沙质量浓度时空分布的动力成因。渤海不同海区表层悬沙质量浓度绝对值差别很大,多年平均最高质量浓度在20~450mg/L变化,高质量浓度集中在近岸河口区及其邻近海域,如黄河口和辽河口地区,低质量浓度区位于渤海中部、渤海海峡以及秦皇岛外海(属于近岸海域却质量浓度常年偏低的特殊海区)。渤海表层悬沙质量浓度具有明显的季节变化特征,风场的季节变化是主要影响因子,各代表性海区悬沙质量浓度与风速之间具有显著正相关关系。悬沙质量浓度与风速之间存在一定时间段的滞后相关。沉积物再悬浮的定量研究表明,除渤海海峡外,渤海其它典型海区表层悬沙质量浓度及其季节变化,均与各自海区风浪和潮流共同作用产生的最大底流速及其季节变化相对应。在渤海,底层沉积物再悬浮的季节变化是影响悬沙质量浓度季节变化最关键的动力过程。  相似文献   

New Discovery of Oligocene Gastropod Opercula from the Yehucheng Formation in Northwestern China     

LI Zhaoyu  LI Yongxiang  ZHANG Yunxiang  XIE Kun  LI Zhichao 《《地质学报》英文版》2022,96(1):61-70

Fourteen species of nonmarine gastropod opercula are found to be in high abundance in the Oligocene upper member of the Yehucheng Formation,Lanzhou Basin,northwest China.They are attributed to two families,namely Bithyniidae and Assimineidae,and four genera,namely Pseudemmericia,Bithynia,Mirolaminatus and Assiminea.Among them,three species are new,and they are Bithynia paramonolithic sp.nov.,B.obliquus sp.nov.,and B.disregularis sp.nov.Some of these species were first discovered in Paleogene strata of the vast Northwest China and can be compared with the opercula recovered from the Paleogene deposits in East and South China.It is inferred from the paleontology and sediment associations that the climate was slightly humid and the fauna probably inhabited the fresh or brackish water of a shallow lake in the Lanzhou Basin during the late early Oligocene period.  相似文献   

Variability of Atlantic Meridional Overturning Circulation in FGOALS-g2简   总被引：3，自引：0，他引：3  

HUANG Wenyu  WANG Bin  LI Lijuan  DONG Li  LIN Pengfei  YU Yongqiang  ZHOU Tianjun  LIU Li  XU Shiming  XIA Kun  PU Ye  WANG Lu  LIU Mimi  SHEN Si  HU Ning  WANG Yong  SUN Wenqi  DONG Fang 《大气科学进展》2014,31(1):95-109

The variability of Atlantic Meridional Overturning Circulation （AMOC） in the pre-industrial control experiment of the Flexible Global Ocean-Atmosphere-Land System model, Grid-point Version 2 （FGOALS-g2） was investigated using the model outputs with the most stable state in a 512-yr time window from the total 1500-yr period of the experiment. The period of AMOC in FGOALS-g2 is double peaked at 20 and 32 years according to the power spectrum, and 22 years according to an auto-correlation analysis, which shows very obvious decadal variability. Like many other coupled climate models, the decadal variability of AMOC in FGOALS-g2 is closely related to the convection that occurs in the Labrador Sea region. Deep convection in the Labrador Sea in FGOALS-g2 leads the AMOC maximum by 3-4 years. The contributions of thermal and haline effects to the variability of the convection in three different regions [the Labrador, Irminger and Greenland-Iceland- Norwegian （GIN） Seas] were analyzed for FGOALS-g2. The variability of convection in the Labrador and Irminger Seas is thermally dominant, while that in the colder GIN Seas can be mainly attributed to salinity changes due to the lower thermal expansion. By comparing the simulation results from FGOALS-g2 and 11 other models, it was found that AMOC variability can be attributed to salinity changes for longer periods （longer than 35 years） and to temperature changes for shorter periods.  相似文献   

地形地貌对地震波放大效应数值模拟研究   总被引：2，自引：0，他引：2  

周兴涛  韩金良  施凤根  王昆 《工程地质学报》2014,22(6):1211-1220

采用FLAC3D 软件进行大量数值模拟,研究了地形地貌对地震波放大效应规律。结果表明:对于单面坡模型,斜坡较低时,坡体对天然地震波和简谐波的峰值加速度在竖直向和顺坡面向产生线性放大效应。斜坡较高时,若坡角低,两种波形的加速度等值线近似平行于坡面,天然地震波坡顶正下方极值性不明显,但随坡角增大而明显,坡面正下方可见若干条与坡面相平行具节律性的极小值条带,随坡角增大向一条极值带转化,简谐波在高低坡脚时坡顶面正下方区域内都出现等间距相间分布具节律性的极值条带,坡面正下方的极值带状性不如天然地震波明显,随坡角增大而消失; 若坡角高,两波形加速度放大系数顺坡面呈相间的极值圈分布。双面坡坡顶宽度越小,山脊越单薄,加速度放大效应越强烈,随坡顶宽度增大,坡肩加速度放大系数趋于稳定,双面坡对加速度放大效应强于单面坡。对加速度放大效应,多峰形双峰形单峰形,坡顶越不规则,加速度放大效应越强烈。V形河谷坡面上半部分加速度放大效应要强于U形河谷,U形河谷的谷底中部对地震波动力响应要强于V形谷。坡面局部不规则性只影响到坡面局部范围内的峰值加速度分布,坡高、坡角、坡顶几何特征为整个峰值加速度分布的控制因素。  相似文献   

湘江竹埠港段河床沉积物元素地球化学特征     

吴雅霁  彭渤  杨霞  张坤  匡晓亮  吴蓓娟  詹婷 《华北地质》2014,(4)

湘江是我国重金属污染最严重的河流之一。本次工作利用X射线荧光(XRF)和电感耦合等离子质谱(ICP-MS)分析技术,对湘江竹埠港沉积物进行主量和微量元素分析。结果表明沉积物主量元素含量变化相对稳定,富集Mn O、P2O5、Fe2O3、Al2O3,亏损Ca O、Na2O。微量元素含量变化较大,亏损Ba、Sc、Mn、Sr而富集其他微量元素。对主量元素和稀土元素进行了分析,表明沉积物物源主要是由上游花岗岩风化所提供。对沉积物进行因子分析和相关性分析,表明沉积物源主要以陆源碎屑为主,并有磷灰石和软锰矿等自生副矿物,Ni、Pb、Cu可能来自人为污染源。地累积指数表明Ba为清洁无污染,重金属V、Cr、Co、Ni、Th、U为轻度污染,重金属Cu、Pb、Zn为偏中度污染,Mn为中度污染,Sc为偏重度污染。其中重金属Cr、Ni、Cu、Pb、Zn、Mn、Sc污染应引起关注。  相似文献   

新疆北部扎河坝坳陷上二叠统沉积环境          下载免费PDF全文

文磊  孙相灿  周新桂  易立  李清瑶  高永进  龚晓星  郭坤 《中国地质调查》2014,6(4):17-23

扎河坝坳陷位于阿尔泰造山带与准噶尔盆地之间,属于中亚造山带的一部分,自早古生代以来经历了准噶尔洋盆的打开和闭合等阶段,富含煤炭和金属矿产,也具有一定的油气勘探前景。研究区火山岩和含煤层系发育,地表风化剥蚀严重,对研究其地层发育特征和沉积环境起到了一定的制约。对扎河坝坳陷新富地1井岩芯样品开展沉积岩微量元素测试,分析结果表明,扎河坝坳陷上二叠统为温暖湿润的淡水沉积环境,表明扎河坝坳陷晚二叠世经历了火山活动和陆相淡水沉积2个阶段,印证了准噶尔洋由俯冲消减向陆内阶段转换的过程。该研究对恢复研究区构造演化及沉积古地理特征具有重要意义。  相似文献