塔克拉玛干沙漠腹地沙粒胶结体的粒度特征

对塔克拉玛干沙漠腹地沙粒胶结体进行溶蚀分散获取组成沙粒,采用激光粒度仪分析粒度成分,并与区域内沙丘沙、垄间平地沙和风沙流输沙的粒度特征进行对比,分析沙粒胶结体的粒度特征。结果表明：（1）沙粒胶结体中沙粒粒径呈多峰态分布,垄间平地沙呈双峰态分布,而沙丘沙和风沙流输沙呈单峰态分布;（2）沙粒胶结体内沙粒分选性较差,偏度属正偏,平均粒径（3.17 Φ）介于沙丘沙（3.10 Φ）和垄间地沙（3.28 Φ）、风沙流输沙（3.67 Φ）之间;（3）沙粒胶结体中沙物质主要组分为细沙和极细沙,与沙丘沙、垄间平沙地沙一致,而与风沙流输沙（极细沙和粉沙）不一致。与沙丘沙、垄间平地沙以及风沙流输沙相比,沙粒胶结体中粉沙、黏土和中沙相对富集,是现代地表物质的混合物;（4）与沙丘沙、垄间平地沙和风沙流输沙相比,沙粒胶结体内沙粒的蠕移-跃移、跃移-悬移截点粒径均偏细,蠕移组分所占比重很高。从组成颗粒的粒度组成来看,沙粒胶结体的形成受局地沙源和风动力的共同影响,是特殊环境条件下现代地表过程的产物。     

Temporal changes in trace elements in brown soil and soybean after long-term fertilization

In agricultural production, specific elements in soil and plants are very important for the soil quality and plant productivity. Trace elements and rare earth elements enter in agri-environment by the application of fertilizers and, through anthropogenic activities, pose important health impacts even at low concentration due to non-biodegradable nature with long half-life. The micro nutrients are essential for human body in a quantity most of less than 100 mg/day. The nutritional element uptake by plants is regulated by availability of the required elements and element accumulation ability of the plants. Therefore, this study was aimed to investigate the accumulation of trace and rare earth elements after long-term application of different fertilizers in soil and soybean uptake. The inorganic fertilizers (NKP) and pig manure were applied to maize-maize-soybean rotation in Alfisols (brown) soil since 1979. Atomic emission spectrometry along with inductively coupled plasma technique was applied to determine trace and rare earth elements. The accumulation pattern of trace elements (TEs) observed in soil was Ni > Co > Se > Mo and rare earth elements (REEs) was found as La > Nd > Tb > Y > Pr > Gd > Er > Yb > Lu. In soybean stem, the TE and REE concentrations were Se > Ni > Co > Mo and Pr > Gd > Er > Yb > Tb > Nd > Lu > La > Y, respectively. Elemental concentrations in the seed samples were Ni > Se > Mo > Co and Pr > Gd > Er > Yb > Tb > Nd > Lu > Y > La. The seed of soybean accumulated Co, Mo, Ni, Gd, Pr, Er, Lu, and Tb more than the stem. Higher concentrations of Se, Nd, Y, and Yb were found in soil. These elements were higher in soybean stem followed by the seed. However, these elements are within safe toxic level and light pollution level.     

A comparative study on the landslide susceptibility mapping using logistic regression and statistical index models

The logistic regression and statistical index models are applied and verified for landslide susceptibility mapping in Daguan County, Yunnan Province, China, by means of the geographic information system (GIS). A detailed landslide inventory map was prepared by literatures, aerial photographs, and supported by field works. Fifteen landslide-conditioning factors were considered: slope angle, slope aspect, curvature, plan curvature, profile curvature, altitude, STI, SPI, and TWI were derived from digital elevation model; NDVI was extracted from Landsat ETM7; rainfall was obtained from local rainfall data; distance to faults, distance to roads, and distance to rivers were created from a 1:25,000 scale topographic map; the lithology was extracted from geological map. Using these factors, the landslide susceptibility maps were prepared by LR and SI models. The accuracy of the results was verified by using existing landslide locations. The statistical index model had a predictive rate of 81.02%, which is more accurate prediction in comparison with logistic regression model (80.29%). The models can be used to land-use planning in the study area.     

Profile of candidate microsatellite markers in <Emphasis Type="Italic">Sebastiscus marmoratus</Emphasis> using 454 pyrosequencing

Sebastiscus marmoratus is an important sedentary ovoviparous fish distributed in near-shore coastal waters from the coast of China to Japan. Candidate S. marmoratus microsatellite markers were developed in the present study using 454 pyrosequencing, and the marker profile was analyzed. A total of 2 000 000 raw sequence reads were assembled to reduce redundancy. Among them, 1 043 dinucleotide, 925 trinucleotide, 692 tetranucleotide, and 315 pentanucleotide repeats were detected. AC repeats were the most frequent motifs among the dinucleotide repeats, and AAT was the most abundant among the trinucleotide repeats. AAAT, ATAG, and ATCC were the three most common tetranucleotide motifs, and AAGAT and AATAT were the most dominant pentanucleotide motifs. The greatest numbers of loci and potentially amplifiable loci were found in dinucleotide repeats, whereas trinucleotide repeats had the fewest. In summary, a wide range of candidate microsatellite markers were identified in the present study using a rapid and efficient 454 pyrosequencing approach.     

面向全空间的管道天然气贸易关联关系挖掘

本文基于全空间信息系统视角,运用复杂网络分析方法,从属性关联关系、时间关联关系、空间关联关系和综合关联关系角度对全球管道天然气贸易复杂网络中主要国家间关联关系进行了挖掘分析和可视化表达。结果表明：管道天然气贸易对战略通道具有路径依赖性和滞后性。贸易格局演化路径稳定,具有明显的“区域小世界”特征。区域资源禀赋差异是管道天然气贸易形成“核心-边缘”网络结构的主要原因。管道天然气贸易主要集中在欧亚大陆。2009年全球管道天然气贸易需求中心集中在欧洲各国,2015年则形成了西欧和中国的双需求核心网络关系。同时,论文基于全球管道天然气贸易复杂网络的挖掘分析和可视化表达,阐述了全空间信息系统的特征,展望了平台的应用。     

多粒度时空对象关联关系基本问题初探

多粒度时空对象关联关系描述现实世界客观实体之间存在的各种关系及其相互影响,是对实体间关联、作用关系的表达,按照其描述主体的不同主要分为时间关联关系、空间关联关系、属性关联关系和综合关联关系。本文从全空间信息系统的背景出发,对多粒度时空对象关联关系的基本概念进行了阐述,明确了其形式化表达方式和分类。在此基础上,对关联关系的构建和管理进行阐述和分析,说明了静态构建方式和动态构建方式的适用场景。关联关系通过约束作用和行为传导机制来维持数据世界的一致性和联动,本文最后对关联关系的约束类型及其定义和关系-行为传导机制进行了简要说明。     

不同电离层格网产品的精度分析

利用全球部分IGS站实测数据,精确提取测站天顶方向的总电子含量,以此作为评估基准,对国内外5家分析中心和2家综合中心（IGS,international GNSS service和iGMAS,international GNSS monitoring & assessment system）的全球电离层格网（global ionosphere maps,GIM）产品在全球范围内的符合精度进行评估。结果表明,不同机构不同类型的GIM产品精度在不同范围的符合精度略有不同。     

内蒙古白音诺尔铅锌矿床成矿时代及其地质意义——来自侵入岩地球化学及年代学的制约

内蒙古白音诺尔铅锌矿床位于大兴安岭成矿带南段,是一个典型的矽卡岩型矿床。为了精确厘定该矿床的成矿时代,对区内与成矿关系密切的花岗闪长斑岩及流纹斑岩中的锆石进行了LA-ICP-MS定年,获得花岗闪长斑岩与流纹斑岩的形成年龄分别为（253.4±0.9）Ma和（133.6±0.7）Ma。岩石地球化学研究表明,花岗闪长斑岩为准铝质岩石,流纹斑岩为过铝质岩石,两者均具有轻重稀土分异明显、富集大离子亲石元素（LILE）、相对亏损高场强元素（HFSE）的特点。结合矿床地质特征及前人在区域上的研究成果,认为白音诺尔铅锌矿床存在两期明显的矿化事件,早期矿化发生在253.4 Ma左右,晚期矿化发生在133.6 Ma左右。白音诺尔铅锌矿床早期矿化很可能与古亚洲洋闭合碰撞后伸展有关,晚期矿化受蒙古-鄂霍茨克洋俯冲的影响。     

一种快速制备不同含水饱和度岩石试样的方法

岩石的含水饱和度对其力学参数有着较大的影响,针对目前关于制备不同含水饱和度岩样普遍存在着精度低、时间长、岩样含水分布不均匀等问题,根据化学-热力学原理,提出一种快速有效制备不同含水饱和度岩样的方法。该方法通过调节放置有岩样的恒湿负压环境的湿度,从而精确控制岩样最终稳定时组分水的逸度,以致控制岩样最终的含水饱和度。由于恒湿环境中水蒸气的逸度是恒定的,当环境中水蒸气的逸度与岩样中组分水的逸度不同时,外界恒湿环境中的水蒸气与岩样中组分水形成逸度差,当环境中水蒸气逸度小于岩样中组分水的逸度时,岩样中组分水渗出;反之,则水渗入岩样,最终岩样中组分水的逸度达到与外界恒湿环境相同的状态,制得相应含水饱和度的岩样。岩样是放置在负压环境中制备的,在负压环境中岩样孔隙中的空气减少,水蒸气在岩样中的渗透加快,从而缩短了岩样达到稳定的时间。根据气液平衡原理,岩样稳定时,岩样各个部分组分水的逸度相同,因此,制得的岩样含水分布均匀。     

路面类型对多年冻土区片块石路基热状态的影响

为了研究不同路面类型对高温多年冻土区路基的热稳定性的影响,基于温度监测数据,针对沥青混凝土路面和水泥混凝土路面下片块石路基温度、热流密度、热收支变化、冻融循环过程及冻土上限变化进行了详细的分析。发现沥青混凝土路面和水泥混凝土路面都对片块石路基的温度有较大的影响,但沥青混凝土路面影响程度和深度远比水泥混凝土路面大。片块石路基中心热收支量呈上升趋势,沥青混凝土路面下其上升速率大于水泥混凝土路面,且路基阳坡热收支量大于阴坡。无论路面材料为沥青混凝土路面还是水泥混凝土路面,片块石路基阴阳坡路肩冻土仍处于不断退化阶段,而阳坡冻土上限下降速率明显大于阴坡。与普通路基相比,片块石层的存在能大幅度抬升或减缓路基冻土上限下降,且浅色水泥混凝土路面更有利于路基的热稳定性。