滇西兰坪铅锌矿区土壤重金属含量的高光谱反演分析

滇西兰坪金顶超大型铅锌多金属矿床是我国最重要的铅锌矿产集中开发区之一。始于20世纪80年代的矿业开发活动逐渐增强,导致该区土壤重金属污染问题不断加重。本文系统开展了兰坪矿区土壤样本的Zn、Pb、As、Cd共4种重金属含量与光谱响应测试实验,详细分析了土壤样本中4种重金属的敏感波段位置及其与土壤中粘土矿物、铁氧化物及碳酸盐矿物之间的赋存关系,构建了4种重金属含量与土壤实测光谱之间的多元线性回归模型。结果表明:(1)区内4种重金属元素含量均超标,且具显著的相关性;(2)重金属含量与土壤光谱反射率、反射率的一阶微分及连续统去除变量具有较高的相关性;(3)用实测光谱的逐步回归方法预测土壤重金属含量的反演模型具有较高的精度,R2均高于0.816。本结果可为大尺度土壤重金属含量监测及其它污染信息提取提供借鉴。     

琼东南盆地深水区松南低凸起油气复式聚集条件与成藏模式

文章利用钻井、测井、地化以及地震资料,分析研究了南海北部琼东南盆地深水区松南低凸起的油气成藏条件。松南低凸起位于中央坳陷带5大(潜在)富生烃凹陷包围中,烃源充足。中新世早期三亚组大型海底扇、中新世早期—渐新世晚期陵水组生物礁、渐新世早期崖城组扇三角洲—滨海相沉积、前古近系古潜山风化壳等多类型储层发育。生烃凹陷深部沟源断裂、崖城组大型疏导砂体和多条古构造脊构成了本地区主要的垂向+侧向输导体系。多层系多类型大中型构造、构造+岩性圈闭发育。研究表明,多成藏要素的耦合促使松南低凸起成为深水区的独有的复式油气聚集区,其成藏模式为它源-侧向-复式成藏,主要成藏组合是三亚组海底扇、三亚组—陵水组生物礁、前古近系古潜山,成藏主控因素为储层与运移。此结论可为南海北部深水区进一步的勘探提供参考。     

长湖浮游动物群落结构及其与环境因子的关系

为研究长湖浮游动物群落结构及其与环境因子间的关系,于2012年4月至2013年1月进行了4次调查采样。共鉴定出浮游动物67种(不包括原生动物),以轮虫种类为主(42种),其丰度与生物量均占据较大优势。浮游动物丰度的季节性差异显著,夏季最高(4412ind./L),冬季最低(831ind./L)。季节间的物种更替率大于59%,但优势种种类的季节变化不明显。优势种共8种,均为轮虫,萼花臂尾轮虫(Brachiouns calyciflorus)、针簇多枝轮虫(Polyarthra trigla Ehrenberg)是四个季节均出现的优势种,P.trigla Ehrenberg的优势度与出现频率均是各个季节的最大值,各季节这两种优势种的丰度和在总丰度的占比均超过59.13%。依据Shannon指数、Pielou指数、Margalef指数评价长湖水体处于中度污染,肥度指数评价长湖处于富营养状态。相关性分析、多元逐步回归方程、冗余分析的结果显示:水温是影响长湖浮游动物群落结构季节变化的关键因子;浮游植物表征含量chl a也是影响长湖浮游动物群落结构的关键因子,总氮、总磷通过影响浮游植物的群落结构间接地影响浮游动物的组成;能耐受较高p H的B.calyciflorus在长湖碱性水体中有较好的适应性;夏季马洪台区较低的溶解氧一定程度上限制了该区域轮虫的生长,总悬浮物通过降低溶解氧对浮游动物产生间接作用;化学需氧量对P.trigla Ehrenberg、螺形龟甲轮虫(Keratella cochlearis)等耐污种的影响较大,并对浮游动物的丰度产生正向作用。     

多个淹没水平圆柱诱发高阶谐波特性的数值与试验研究

基于势流理论采用时域高阶边界元方法建立了模拟非线性波浪与淹没水平双、三圆柱作用的数值水槽模型,其中采用混合欧拉-拉格朗日方法更新自由水面,四阶Runga-Kutta方法进行时间步进。利用两点法分离得到潜体下游高阶自由波,进而研究潜体间距、布置形式等对高倍频自由波的影响。同时在物理水槽内开展多潜体高阶谐波物理模型试验,并将试验结果与数值结果进行对比,吻合较好。研究发现:淹没双圆柱下游高阶谐波幅值随潜体间距呈现周期性振荡变化,其振荡的重现距离约为波长一半。而淹没三圆柱下游的高阶谐波随第一个间距呈周期性振荡变化,随第二个间距的增大而减小。     

Female ornaments signal own and offspring quality in a sex‐role‐reversed fish with extreme male parental care

Although female ornaments have been described in many taxa, the full spectrum of information conveyed by such traits together with the potential male fitness benefits are far from fully understood. Here, we used a sex‐role‐reversed species, the black‐striped pipefish, Syngnathus abaster, where females are the ornamented sex and intensively compete for mates who present an extreme form of paternal care (male pregnancy). We investigated what information is conveyed by female traits and if males are using it during mate choice. We further assessed which traits would reflect offspring quality at birth. We found that although body length generally portrays information on female reproductive potential (gonadosomatic index and oocyte diameter), it does so indirectly. Different aspects of the female traits, such as stripe width and trunk broadness, were found to be better direct indicators. When size is kept constant, males prefer females with wider stripes. Moreover, stripe coloration was found to reflect offspring quality as darker‐striped females produced larger newborns. Our observations suggest that in a species with exclusive paternal care, independently from the male's direct investment in reproduction, female contribution decisively impacts male fitness. Thus, at least in sex‐role‐reversed species such as the black striped pipefish, female ornaments can be selected in an analogous way to those of males in species with conventional sex roles (i.e. by mate choice).     

New Relationship for Estimation of Wave Overtopping on Vertical Walls

Soft computing tools in the form of combination of multiple nonlinear regression and M5'' model tree were used for estimation of overtopping rate at the vertical coastal structures. For reliable and precise estimation of overtopping rate, the experimental data available in the database CLASH were used. The dimensionless overtopping rate was estimated in terms of conventional dimensionless parameters including the relative crest freeboard R_c/H_s, seabed slope tanθ, deep water wave steepness S_om, surf similarity ξ_om and local relative water depth h_t/H_s. The accuracy of the new model was compared with other existing models and also evaluated with some field measurements. The results indicated that the model presented in this paper is more accurate than other existing models. With statistical parameters, it is shown that the accuracy of predictions in the new model is better than that of other models.     

Interannual Variation of Multiple Tropical Cyclone Events in the Western North Pacific

The interannual variability of occurrence of multiple tropical cyclone(MTC) events during June-October in the western North Pacific(WNP) was examined for the period 1979-2006.The number of the MTC events ranged from 2 to 9 per year,exhibiting a remarkable year-to-year variation.Seven active and seven inactive MTC years were identified.Compared to the inactive years,tropical cyclone genesis locations extended farther to the east and in the meridional direction during the active MTC years.A composite analysis shows that inactive MTC years were often associated with the El Nin o decaying phase,as warm SST anomalies in the equatorial eastern-central Pacific in the preceding winter transitioned into cold sea surface temperature(SST) anomalies in the concurrent summer.Associated with the SST evolution were suppressed low-level cyclonic vorticity and weakened convection in the WNP monsoon region.In addition to the mean flow difference,significant differences between active and inactive MTC years were also found in the strength of the atmospheric intraseasonal oscillation(ISO).Compared with inactive MTC years,ISO activity was much stronger along the equator and in the WNP region during active MTC years.Both westward-and northward-propagating ISO spectrums strengthened during active MTC years compared to inactive years.The combined mean state and ISO activity changes may set up a favorable environment for the generation of MTC events.     

A Comparison of Three Kinds of Multimodel Ensemble Forecast Techniques Based on the TIGGE Data

Based on the ensemble mean outputs of the ensemble forecasts from the ECMWF (European Centre for Medium-Range Weather Forecasts),JMA (Japan Meteorological Agency),NCEP (National Centers for Environment...     

密集井点小泵量基坑降水技术的应用

介绍了在水源补给充分、水位降深较大的基坑施工中,采用密集井点小泵量连续抽水控制地下水位,使降水漏斗曲面平缓,减小基坑周围地面沉降的风险的方法,以及取得的良好的降水效果。     

Alteration and Reformation of Hydrocarbon Reservoirs and Prediction of Remaining Potential Resources in Superimposed Basins

<正>Complex hydrocarbon reservoirs developed widely in the superimposed basins of China formed from multiple structural alterations,reformation and destruction of hydrocarbon reservoirs formed at early stages.They are characterized currently by trap adjustment,component variation, phase conversion,and scale reformation.This is significant for guiding current hydrocarbon exploration by revealing evolution mechanisms after hydrocarbon reservoir formation and for predicting remaining potential resources.Based on the analysis of a number of complex hydrocarbon reservoirs,there are four geologic features controlling the degree of destruction of hydrocarbon reservoirs formed at early stages:tectonic event intensity,frequency,time and caprock sealing for oil and gas during tectonic evolution.Research shows that the larger the tectonic event intensity,the more frequent the tectonic event,the later the last tectonic event,the weaker the caprock sealing for oil and gas,and the greater the volume of destroyed hydrocarbons in the early stages.Based on research on the main controlling factors of hydrocarbon reservoir destruction mechanisms,a geological model of tectonic superimposition and a mathematical model evaluating potential remaining complex hydrocarbon reservoirs have been established.The predication method and technical procedures were applied in the Tazhong area of Tarim Basin,where four stages of hydrocarbon accumulation and three stages of hydrocarbon alteration occurred.Geohistorical hydrocarbon accumulation reached 3.184 billion tons,of which 1.271 billion tons were destroyed.The total volume of remaining resources available for exploration is～1.9 billion tons.