InSAR可检测的最大最小变形梯度的函数模型研究

InSAR干涉图中的相位噪声是相干性和视数的函数.InSAR能检测的地表最大最小形变梯度,除了受到InSAR硬件的限制外,还直接受到InSAR干涉图中噪声强弱的影响.此外,由于多视处理会改变像元的大小,也会引起可检测的最大最小形变梯度显著变化.本文研究了InSAR可检测的地表最大最小形变梯度与相干性和视数的关系,并建立了视数为1、5和20时（ERS和ENVISAT常采用的多视数）InSAR可检测的最大最小形变梯度的经验函数模型.最后,本文用伊朗Bam地区的Enivsat ASAR数据进行了试验,结果表明该模型能够准确地判别不同视数和相干性情况下地表变形能否被InSAR技术所检测.与Baran只考虑了相干性的模型相比,本文的模型适用范围更广.     

Discrimination of abiogenic and biogenic alkane gases

We have combined the analytical data of the carbon isotope distribution pattern, R/Ra and CH4/3He values of abiogenic and biogenic (referring to the thermogenic and bacterial or microbial) alkane gases in China with those of alkane gases from USA, Russia, Germany, Australia and other countries. Four discrimination criteria are derived from this comparative study: 1) Carbon isotopic composition is generally greater than -30‰ for abiogenic methane and less than -30‰ for biogenic methane; 2) Abiogenic alkane gases have a carbon isotopic reversal trend (δ 13C1> δ 13C2> δ 13C3> δ 13C4) with δ 13C1>-30‰ in general; 3) Gases with R/Ra >0.5 and δ 13C11 δ 13C2>0 are of abiogenic origin; 4) Gases (meth- ane) with CH4/3He≤106 are of abiogenic origin, whereas gases with CH4/3He≥1011 are of biogenic origin.     

摘除眼柄对中华绒螯蟹精巢发育及其氨基酸含量的影响

本文报道了摘除眼柄对中华绒螯蟹精巢发育及其氨基酸含量的影响,实验分成两组,即摘除眼柄实验组和对照组。结果表明：对照组粗巢内生殖细胞种类多,各期的生殖细胞都有,与之比较,实验组的种类少,只有精子期细胞,说明摘除眼柄可促进精巢发育,加快精子的形成,并使精巢发育同步化,摘除眼柄对精巢氨基酸含量有一定的影响,本文探讨了中华绒螯蟹性早熟可能的机制。     

Comparison between reconstructions of global anthropogenic land cover change over past two millennia

Three global datasets, the History Database of the Global Environment (HYDE), Kaplan and Krumhardt (KK) and Pongratz of reconstructed anthropogenic land cover change (ALCC) were introduced and compared in this paper. The HYDE dataset was reconstructed by Goldewijk and his colleagues at the National Institute of Public Health and the Environment in Netherland, covering the past 12 000 years. The KK dataset was reconstructed by Kaplan and his colleagues, the Soil-Vegetation-Atmosphere Research Group at the Institute of Environmental Engineering in Switzerland, covering the past 8000 years. The Pongratz dataset was reconstructed by Pon-gratz and her colleagues at the Max Planck Institute for Meteorology in Germany, covering AD 800-1992. The results show that the reconstructed datasets are quite different from each other due to the different methods used. The three datasets all allocated the historical ALCC according to human population density. The main reason causing the differences among the three datasets lies on the different relationships between population density and land use used in each reconstructed dataset. The KK dataset is better than the other two datasets for two important reasons. First, it used the nonlinear relationship between population density and land use, while the other two used the linear relationship. Second, Kaplan and his colleagues adopted the technological development and intensification parameters and considered the wood harvesting and the long-term fallow area resulted from shifting cultivation, which were neglected in the reconstructions of the other two datasets. Therefore, the KK dataset is more suitable as one of the anthropogenic forcing fields for climate simulation over the past two millennia that is recently concerned by two projects, the National Basic Research Program and the Strategic and Special Frontier Project of Science and Technology of the Chinese Academy of Sciences.     

Characteristics of clustering debris flows in Wenchuan earthquake zone

Clustering debris-flow events, namely many debris flows simultaneously triggered by a regional rainstorm in a large-scale mountainous area, occurred in four regions of Wenchuan earthquake stricken areas in 2008 and 2010. The characteristics of the clustering debris flows are examined with regard to triggering rainfall, formation process, and relationship with the earthquake by field survey and remote sensing interpretation. It is found that the clustering events occurred nearly at the same time with the local peak rainstorms, and the rainfall intensity-duration bottom limit line for clustering debris flows is higher than the worldwide line. It means that more rainfall is needed for the occurrence of the clustering debris flows. Four kinds of major formation processes for these debris flows are summarized： tributary-dominated, mainstream- dominated, transformation from slope failures, and mobilization or liquefaction of landslide. The four regions has a spatial correlation with the strong- quake-influenced zone with the peak ground acceleration = 0.2 g and the seismic intensity 〉 X.     

塔东北库鲁克塔格地区中上寒武统白云岩类型与孔隙演化*

对塔东北库鲁克塔格隆起的乌孜里塔格剖面中上寒武统白云岩的岩石学、成岩作用、裂隙—孔隙发育与充填等特征研究认为：可划分为有序度逐渐增加的粉晶白云岩、粉细晶白云岩、中细晶白云岩和中粗晶白云岩及晶洞中的中粗晶、巨晶和鞍形白云石等4种类型;分别对应于早期准同生—浅埋、中浅埋藏、中等埋藏和构造断裂—热液（热卤水）作用4期的成岩阶段;其中,沿走滑断裂—裂隙带、呈不规则的“侵入体” 具有斑点状、条纹—条带、雁行状—斑马、角砾状和不规则状结构的中粗晶、粗晶、巨晶（部分为鞍形）白云岩（石）,一般不发光或呈昏暗的暗红色,具有与加拿大西部盆地典型的热液白云岩相似的特征;中上寒武统白云岩存在4～5期构造裂隙和3期以上的充填作用;热液白云岩中以晶间孔、晶间溶孔（洞）、裂隙及沿裂隙的扩溶孔洞为主,主要有二世代的白云石和方解石和少量沥青、石英、微量硬石膏和重晶石等多期充填作用。与西加盆地寒武系部分或全部交代充填缝洞及角砾构造、受来自落基山造山带的晚白垩世至古近系拉腊米（Laramide）构造的被排驱的热液流体交代形成的典型热液白云岩稍有不同,海西晚期（晚二叠世）及燕山—喜马拉雅期（晚白垩世—第四纪）沿挤压—走滑断裂排驱的地层热卤水循环—扩散与交代作用可能是本区热液白云岩的主要成因,储集空间主要由中、晚期构造断裂—裂隙（溶蚀）所致,但不排除成岩早期埋藏或晚期大气水作用对其影响。     

Bohaisea-9145海洋耶氏酵母碱性脂肪酶基因的克隆、异源表达和重组酶酶学性质

采用基因重组和分子生物学相关技术,对Yarrowia lipolytica Bohaisea-9145海洋低温碱性脂肪酶(Y.lipolytica Bohaisea-9145,LipYp)基因lipYp(1116bp)克隆并在Pichia pastoris中进行了异源真核表达研究。通过MD和MM平板及PCR扩增,筛选和鉴定了重组子。结果表明,阳性重组子经摇瓶发酵54h后上清液酶活力达到1956U/ml。发酵液经两步纯化得到在SDS-PAGE上显示为单一条带的重组脂肪酶。实验同时研究了不同反应温度、pH值对重组LipYp活力和稳定性的影响,结果显示重组LipYp最适反应温度和pH分别为35℃和8.5,在pH7.0-10.5之间以及45℃以下有较好稳定性。另外,重组脂肪酶对中长链对硝基苯基酯类和甘油三酯类(C10-C12)有较强的水解能力。     

天津市滨海新区风暴潮灾害风险评估

根据经地面沉降订正后的1959～2005年海河闸站年极值最高潮位数据,运用Gumbel型和P～型计算方法求得不同频率年极值高潮位;根据历史上典型风暴潮淹没情景,在现有防潮堤的情况下,运用圣维南和薄壁堰自由出流等公式推求不同频率风暴潮进潮量;利用开发的无源和有源淹没程序计算不同频率风暴潮淹没范围。结果如下:天津市滨海新区出现频率为5%、1%和0.5%的年最高潮位分别达4.54m、4.92m和5.08m(大沽零点基面);现状条件下,3种频率风暴潮可能淹没的土地面积分别达km2、km2和118.50km2;淹没损失分别达1.79×108元、3.93×108元和5.06×108元。     

北京典型区地面沉降演化特征与成因分析

北京从20世纪50、60年代发现地面沉降以来,其一直呈快速发展的态势。在过去的几十年里,北京市地面沉降的范围和速度逐年增加。本文以北京市典型地面沉降区为研究区,选择永久散射体合成孔径雷达干涉测量技术所获取的2004-2010年间北京地面沉降信息作为主要数据源,补充水准测量数据（1955-2010年）,从空间分布和时序变化2个角度,分析北京市平原典型区地面沉降演化特征。结合地下水动态监测网数据、土地利用数据,采用GIS空间分析,研究各因素和地面沉降之间的时空响应关系。结果表明,北京地区地面沉降严重区域面积不断扩大,且局部不均匀程度逐渐增加。在研究期内,地下水水位变化在时间和空间上与地面沉降有较高的一致性,地下水超量开采是影响北京地区地面沉降的最主要因素,而城市发展过程中的工程活动也是影响地面沉降时空分布特征的因素之一。研究结果可为北京市地面沉降防控提供一定的科学依据。     

栅格地理计算并行算子对区域计算算法并行化的可用性分析——以多流向算法为例

栅格地理计算并行编程库的研发有助于实现对栅格地理计算算法的并行化。在现有的研究中,Qin 等(2014)设计并初步研发的栅格地理计算并行算子(PaRGO),在设计思路上能较好地隐藏与并行编程软硬件环境相关的复杂细节,实现栅格地理计算通用步骤的并行化,且较其他类似思路的编程库而言,PaRGO能兼容多种常用的并行计算平台,具有明显优势。但PaRGO目前在设计上仅直接支持本地、邻域及全局计算特点的栅格地理计算算法并行化,对于更为复杂的区域计算特点算法并行化的支持能力尚未探究。对此,本文选取栅格数字地形分析中具有区域计算特点、递归设计的多流向算法为算例,利用PaRGO进行并行化设计、实现及测试,以计算时间、相对加速比和相对并行效率为定量指标。通过可运行性和并行性能进行评价,结果表明:PaRGO虽然不能直接支持对递归的多流向算法进行并行化,但在根据多流向计算的原理将该递归算法转变为非递归的设计之后,可将算法由原区域计算改造为邻域迭代计算,就能利用PaRGO 实现并行化,并得到较好的并行效果。在集群环境下,MPI版本并行程序的并行效果优于MPI/OpenMP混合版本。