福建热带气旋风雨空间分布特征及风险评估

根据1961—2010年热带气旋资料,按登陆地段或移动路径将登陆影响福建的热带气旋分为11种路径,分析各种路径的致灾因子空间分布特征,结果表明:热带气旋雨灾最严重的区域位于北部和中部沿海,风灾最严重的是南部沿海;从路径来看,降水强度最强是登台入闽北路径,强风区域最大的是直接登陆闽南路径和登台入闽中部路径,风力最强的是登台入闽南路径。采用相关系数客观赋权法建立了致灾因子风险评估模型,分析不同热带气旋路径致灾因子风险等级,登台入闽中和登台入闽北路径风险最大,其次是直接登陆闽南和登陆珠江口及以东路径;高风险区域 (包括次高危险和高危险区) 集中在沿海地区、闽西和闽北的局部。     

Overview of the UAV—Based Eddy Covariance Fluxes Measurements Technique

Airborne Eddy Covariance (EC) method is one of the most effective ways to measure the turbulent fluxes over regional scale directly. The turbulent fluxes from airborne EC method have the same spatial scale with the pixel scale of remote sensing image and the grid scale of land-surface models, which is very important for the simulation of regional or global land-surface fluxes. UAV-based eddy covariance method could achieve the observation of turbulent fluxes in a multi-period and multi-sorties way, and the observation result is reliable and the application is inexpensive. It is an important development direction for airborne flux observation technique. After the introduction of the main technical characteristics of the airborne EC method, this paper reviewed the worldwide progress in UAV-based fluxes measurements system from these aspects of the specifications of the UAVs, the integrated instruments, and the analysis of the application cases. Then, the main sources of uncertainty affecting the UAV-based fluxes measurements were discussed. At last, the shortcomings of the current UAV-based flux observation system were summarized. A brief outlook about UAV-based fluxes measurements technique was also given.     

河南固始地区矽卡岩型铅锌矿地质特征与成因

河南固始地区矽卡岩型铅锌矿为小型层控矽卡岩型铅锌矿,矿体赋存于下石炭统花园墙组地层中,主要受地层控制,区内龟（山）—梅（山）断裂带、杨山背斜及北西西向断裂为主要控矿构造。燕山期中酸性小岩体在有利的构造部位多次侵入,与围岩下石炭统花园墙组的石英砂岩、钙硅质石英砂岩、钙硅质粉砂岩的“硅钙面”发生交代作用,从而富集成矿,燕山期中酸性小岩体是矿区主要的物质来源和热源,矿体形成受构造影响显著,矿体规模与构造附近的侵入体规模成正比。矿区内物化探对矿体均有良好的指示。研究成果对于该区进一步扩大找矿远景具有一定的借鉴意义。     

鄂尔多斯地区奥陶纪构造古地理演化与沉积充填特征

鄂尔多斯地区在奥陶纪处于华北克拉通板块的西南边缘地区。由于受秦岭—祁连—贺兰三叉裂谷系开裂—聚合作用的影响,奥陶纪鄂尔多斯地区与华北克拉通已开始出现明显构造与沉积作用的分异,突出表现为奥陶纪沉积期鄂尔多斯东部大规模膏盐岩沉积层的发育。古构造分析表明鄂尔多斯地区奥陶纪总体呈现为“三隆—两坳—一古陆”的古构造分布格局;奥陶纪经历了冶里—亮甲山期的早期边部海侵、马家沟期振荡性的整体沉降海侵以及平凉—背锅山期的西南边缘快速沉陷的古地理演化过程,表现出较强的阶段性演化特征。鄂尔多斯地区奥陶纪整体的沉积充填作用具有以下重要特征:一是受中央古隆起控制、东西向沉积分异明显;二是随时代演进,早中期以内源沉积为主,晚期则以混源或陆源碎屑沉积为主;三是西南边缘沉积巨厚,是奥陶纪最为活跃的构造沉降区。     

考虑微观结构的非饱和渗透系数计算公式

分维理论是预测非饱和渗透系数的一种常用方法。在对有侧限条件下高庙子膨润土的非饱和渗透系数的试验结果分析后,发现分维理论并不适用,其缺陷在于不能够反映膨润土这种特殊粘土在水化过程中的微观结构变化。因为膨润土是一种纳米材料,其小孔隙和大孔隙分布在水化过程中都会发生变化,而一般性粘土和砂土没有这种特殊的物理化学特性。结合Kozeny—Carman关于多孔介质的半经验公式,提出了半经验一半理论的考虑微结构的膨润土的非饱和渗透系数计算公式。在对高庙子膨润土的扫描电镜试验和压汞试验资料分析的基础上,定性验证了所提出公式的正确性。     

山东半岛东北部新发现近EW向活断层

山东半岛东北部地区晚第四纪的构造活动以整体性抬升为主,内部的断裂活动相对较弱,晚更新世以来的断裂活动仅分布在局部地区,新发现的东殿后断裂是其中的1条。断裂总体走向近EW,全长约20km,地貌上表现为由3条河流上游组成的谷地。断裂错断的最新地层的热释光年龄为84～75kaBP,上覆坡积角砾层的热释光年龄为64kaBP,断裂发育的松软断层泥的热释光年龄为82kaBP。断裂的剖面特征和断盖地层的年龄表明,东殿后断裂的最新活动时代是晚更新世早中期,垂直活动速率不<016mm/a,晚更新世晚期以来停止活动;断裂的最大潜在地震为6级     

Influence of the biological carbon pump effect on the sources and deposition of organic matter in Fuxian Lake,a deep oligotrophic lake in southwest China

Biological carbon pumping (BCP) is a key process in which dissolved inorganic carbon in terrestrial aquatic ecosystems is utilized by aquatic autotrophs for photosynthesis and transformed into autochthonous organic matter (AOC). However, the mechanisms underlying BCP and the amount of generated AOC deposited effectively, are still poorly understood. Therefore, we conducted a systematic study combining modern hydrochemical monitoring and a sediment trap experiment in Fuxian Lake (Yunnan, SW China), the second-deepest plateau, oligotrophic freshwater lake in China. Temperature, pH, EC (electrical conductivity), DO (dissolved O₂), [HCO₃⁻], [Ca²⁺], SI_c, partial CO₂ (pCO₂) pressure, and carbon isotopic compositions of HCO₃⁻ (δ¹³C_DIC) in water from Fuxian Lake all displayed distinct seasonal and vertical variations. This was especially apparent in an inverse correlation between pCO₂ and DO, indicating that variations of hydrochemistry in the lake water were mainly controlled by the metabolism of the aquatic phototrophs. Furthermore, the lowest C/N ratios and highest δ¹³C_org were recorded in the trap sediments. Analyses of the C/N ratio demonstrated that the proportions of AOC ranged from 30% to 100% of all OC, indicating that AOC was an important contributor to sedimentary organic matter (OC). It was calculated that the AOC flux in Fuxian Lake was 20.43 t C km⁻² in 2017. Therefore, AOC produced by carbonate weathering and aquatic photosynthesis could potentially be a significant carbon sink and may have an important contribution to solving the lack of carbon sinks in the global carbon cycle.

     

“海上丝绸之路”战略下的我国港口功能布局研究——基于临港产业空间集聚视角

作为区域经济的增长极,港口对相关产业的集聚和发展有重要的作用。文章以全国省际数据为基础,运用探索性空间统计变量Moran's I指数,分析能源、钢铁、交通运输、运输设备制造等港口相关产业的地理集聚模式,研究各产业与港口的互动关系,以此评价我国港口对产业发展的服务功能和带动作用,并就港口与产业布局提出相关建议。     

Development of Two New Copper Isotope Standard Solutions and their Copper Isotopic Compositions

In this study, two new laboratory reference solutions for testing Cu isotopic composition were established and investigated. Two commercially available pure copper products, copper plate and copper wire, were dissolved in 1000‐ml Teflon^® bottles, to produce 200 μg ml^?1 stock solutions (hereafter referred to as NWU‐Cu‐A and NWU‐Cu‐B), and cryogenically stored. The Cu isotopic compositions of the two samples were determined in three different laboratories using multi‐collector inductively coupled plasma‐mass spectrometry, and the Cu isotopic compositions obtained from the standard‐sample bracketing method were consistent within the two standard deviation (2s) range. The Cu isotopic compositions of the NWU‐Cu‐A and NWU‐Cu‐B standard solutions were δ⁶⁵Cu = +0.91 ± 0.03‰ (2s, n = 42) and δ⁶⁵Cu = ?0.05 ±0.03‰ (2s, n = 49), respectively, relative to the reference material NIST SRM 976.