Emergence patterns and microhabitat preference of aquatic dance flies (Empididae; Clinocerinae and Hemerodromiinae) on a longitudinal gradient of barrage lake system

Aquatic dance flies (Empididae; Clinocerinae and Hemerodromiinae) are important components of freshwater assemblages, especially in running waters. They are predators as larvae and adults and thus essential for understanding aquatic food webs. This study was conducted in Plitvice lakes National Park (Croatia) representing a wide variety of freshwater habitats (springs, streams, lakes and tufa barriers). Adults were collected monthly from March 2007 until March 2009 using pyramid-type emergence traps at 13 locations. A total of 3865 specimens comprising 18 species were collected. The dominant genus was Chelifera, while the most abundant species was Hemerodromia unilineata. All species were univoltine except Chelifera precabunda, Chelifera pyrenaica and Chelifera stigmatica that were bivoltine. Considerable differences in composition and structure of aquatic dance flies assemblages were recorded along a longitudinal gradient of studied sites, primarily related to differences in physical and chemical parameters of water. Water temperature was the main factor influencing the timing of emergence. Hemerodromia species preferred variable water temperature throughout the year while the majority of the Chelifera species preferred stable water temperature characteristic of spring sites. Furthermore, discharge affected assemblage composition of aquatic dance flies. The highest abundance of aquatic dance flies was recorded in lotic habitats with fast water current over substrates of moss, gravel and particulate tufa with detritus. These results give a new insight on microhabitat preference and their distribution on unique karstic habitats.     

建筑物加载过程中高精度变形监测研究

采用TM30测量机器人对图书加载过程中笔者所在院校图书馆进行变形监测,对变形观测数据进行严密平差,获取监测结果;进而根据监测结果绘制变形等值线,表达出各个方向的变形量,直观表达危险变形区域;最后获取建筑物加载过程中的变形监测规律。在图书加载初期,南北方向变形呈不稳定S型,而东西方向变形从初期开始变形趋于围绕图书加载位置。建筑物长、宽对建筑物稳定有影响,在建筑物加载位置需要增加承重及在外围采取防护措施。该研究对建筑设计有实际意义。     

短波红外光谱技术在矽卡岩型矿床中的应用——以鄂东南铜绿山铜铁金矿床为例

铜绿山铜铁金矿床是长江中下游铜铁多金属成矿带最重要的矽卡岩型矿床之一,矿床的形成与铜绿山石英闪长岩株体密切相关,矿体主要沿北北东向断裂产于石英闪长岩与大理岩/白云质大理岩的接触带,形成钙-镁复合型矽卡岩铜多金属矿化。围岩蚀变由致矿岩体到接触-蚀变矿化中心为:绢云母-绿泥石-钾化带、高岭石-绿泥石-弱矽卡岩化带、皂石-绿泥石-强矽卡岩化带。蚀变矿化期次可分为岩浆-热液期和表生期,其中,岩浆-热液期可分为矽卡岩阶段、退化蚀变阶段、氧化物阶段、硫化物阶段和碳酸盐阶段。绿泥石是钻孔岩芯中出现最多且分布最为广泛的蚀变矿物之一。经短波红外光谱(SWIR)研究发现,从蚀变矿化中心到外围,绿泥石出现由铁绿泥石/铁镁绿泥石逐渐转变为镁绿泥石,且绿泥石Fe-OH特征吸收峰位值(Pos2250)显示出从高值变为低值的趋势。结合其他蚀变矿物的空间分布特征,文章提出绿泥石的高Fe-OH特征吸收峰位值(Pos22502253 nm)与金云母、蛇纹石、绿帘石、皂石和高岭石的大量出现,对指示铜绿山矽卡岩型矿床的矿化中心具有一定的作用。     

高频电磁法在鄂尔多斯盆地伊盟隆起区砂岩型铀矿勘探中的应用

砂岩型铀矿已经成为中国非常重要的铀矿类型,不少资料表明,在含油气盆地中,砂岩型铀矿与油气藏的关系密切,大型沉积盆地不但是油气田勘探的重要靶区,也是寻找砂岩型铀矿的重要方向。在地球物理勘探中,每种地球物理方法都有其应用条件和优缺点,寻找一种快速经济有效的适合铀矿勘查手段显得非常重要。高频电磁法是一种野外数据采集设备轻便、观测时间短、可快速密点连续测量的方法。本文针对砂岩型铀矿的特点,在应用该项技术进行铀矿勘查方面进行了一系列研究,自行开发了针对性的二维反演软件,有效提高了测量分辨率和地质解释的精度。本文介绍了高频电磁法在寻找砂岩型铀矿勘探方面的应用实例与效果,提出了以后开展类似工作的建议。     

综合指数法在石城崮铁矿采空区稳定性评价中的应用

据初步统计,临沂市现有非煤矿山采空区101个,面积787万m2。在目前的资金和技术条件下,难以对所有采空区都进行工程治理,必须分类处理。为正确决策采空区的治理措施,需要全面评估采空区的稳定性。本文在充分调研各种采空区稳定性评价方法的基础上,应用综合指数法对石城崮铁矿采空区的稳定性进行了评价分析。通过计算地质因素和开采技术条件的综合评价指数,最终得到了该采空区的综合评价结果。评价结果显示该采空区目前处于较稳定状态,该评价结果与实际情况吻合较好。     

用优势应力分量逼近方法反演分析某水电站地下厂房区地应力状态

本文叙述了应用有限元优势应力分量逼近反演分析地应力场的方法。该方法通过少数点实测应力结果,结合工程地质资料,采用有限元数值模拟分析的方法反演工程区初始应力场。利用该方法并结合某水电站工程的实际情况进行了电站主厂房的地应力场分析,得到了在优势应力分量上与实测值相拟合的工程区剖面最大、最小主应力量值及其方向的分布图,并对工程区整体应力分布状况做了分析与探讨。     

Evaluation of equivalence between different methods for enumeration of fecal indicator bacteria before and after adoption of the new Bathing Water Directive and risk assessment of pollution

The quality of bathing water is of considerable public importance due to the possibility of fecal contamination. In 2009, Croatia implemented the new European Bathing Water Directive (BWD, 2006/7/EC) establishing stricter microbiological standards for new parameters with new reference methods. This study aims to evaluate the equivalence of different methods according to the old and revised BWD and to provide the possibility of data comparison. Furthermore, the directive requires the establishment of the bathing water profile (BWP) for pollution risk assessment. The estimation of consistency of pollution risk assessment with obtained microbiological results was also performed.     

基于时间序列的InSAR相干性量级估计

本文提出了一种适用于InSAR数据处理的自适应相干性量级估计方法,该方法能够满足复信号随机平稳的假设前提,并兼顾运算效率与估计精度.此方法生成的相干图具有很好的分布特征,避免了影像空间分辨率的损失.提出的算法分为两个步骤:(1)根据地物后向散射特性,对时间序列SAR影像进行聚类分析,选择具有同分布的样本,保证SAR影像质地平稳条件;(2)对干涉图进行条纹频率估计,采用极大似然(ML)条纹频率估计方法去除系统相位引起的复信号非平稳性,并根据Cramer-Rao边界条件改善条纹频率的估计精度.以美国南加州洛杉矶地区的ENVISAT ASAR数据集为例,本文将新方法与现有方法进行了量化分析.结果表明,较传统方法而言,基于时间序列的相干性估计方法能够得到更可靠、精度更高、空间特征更鲜明的干涉相干图.     

基于CPU和GPU协同处理的光学卫星遥感影像正射校正方法

本文系统地探讨了基于CPU和GPU协同处理的光学卫星遥感影像正射校正方法。首先使用“层次性分块”策略设计了基于CPU和GPU协同处理的正射校正方法,然后通过配置选择优化和存储层次性访问等手段进一步提高了方法执行效率。在Tesla M2050 GPU上对资源三号卫星下视全色影像进行正射校正的实验结果表明,本文方法大幅提高了光学卫星遥感影像正射校正效率,与传统串行正射校正算法相比,加速比最高达到110倍以上,相应的处理时间压缩至5s以内,可满足对大数据量光学卫星遥感影像进行快速正射校正的要求。     

Multi-resolution seamless image database

This paper presents the basic concepts and principles, data structure and high efficient spatial index for multi-resolution image database. The database is characterized by arrangement of multi-resource image data and seamless mosaic, distribution-based storage and management, integration with other spatial database software such as GeoStar and GeoGrid developed by Wuhan Technical University of Surveying and Mapping.