Chronological constraints on the tectonic evolution of the Chinese Tianshan Orogen through detrital zircons from modern and palaeo-river sands

The Chinese Tianshan Orogen marks prolonged and complicated interactions between the southwestern Palaeo-Asian Ocean and surrounding blocks. New and previously published detrital zircon chronological data from modern and palaeo-river sands were compiled to reveal its tectonic evolution. It is characterized by predominant Palaeozoic as well as minor Mesozoic and Precambrian detrital zircon ages with a multimodal characteristic. The oldest Phanerozoic zircon population (peaking at 475 Ma) is a result of subduction and closure of the early Palaeozoic Terskey Ocean. However, the absence of this peak in the Chinese North and southern South Tianshan suggests that subductions of the North and South Tianshan oceans may not have initiated until the Late Ordovician with subsequent 460–390 and 360–320 Ma arc magmatism. Similar to the magmatic suite in classic collisional orogens, the youngest massive 320–270 Ma magmatism is suggested to be post-collisional. The North and South Tianshan oceans therefore probably had their closure to form the Chinese Tianshan Orogen during the late Carboniferous. The weak Mesozoic intra-plate magmatism further rejects a late Permian–Triassic Tianshan Orogen due to a lack of extensive syn- and post-collisional magmatism. Moreover, diverse Precambrian detrital zircon age patterns indicate that the surrounding blocks have distinct evolutionary processes with short-term amalgamation during the Meso- to Neoproterozoic.     

A Review of Study on Fe-C Interaction and Their Adsorption Properties to Soil Heavy Metal

Nowadays, the Fe-C coprecipitate mechanism is recognized by more and more scholars and becomes the hot topic in the environmental science. On the basis of discussing the interaction between iron oxide and organic matter, and the adsorption research progress of Fe-C complexes on heavy metals, the immobilization potential of Fe-C complexes on heavy metals in polluted soil were illustrated. The surface properties and physical characterizations of iron oxide are changed regularly with the interaction of organic matter, which lead to the higher adsorption capacity of Fe-C complexes in contrast to single iron oxide. Besides, the influences of pH values, organic matter types and surface properties of iron oxides on the adsorption capacity of Fe-C complexes on heavy metals were discussed. The excellent adsorption performance of Fe-C complexes in certain conditions will provide important theoretical basis for contaminated soil remediation.     

Multi-scale variation characteristics of polar vortex at 10 hPa in the Southern Hemisphere

By use of 1948-2007 NCEP/NCAR reanalysis monthly geopotential data, a set of circulation indices are defined to characterize the polar vortex at 10 hPa in the Southern Hemisphere, including area-(S), intensity-(P) and centre position-(λc , φc) indices. Sea-sonal variation, interannual anomalies and their possible causes of 10 hPa polar vortex in the Southern Hemisphere are analyzed by using these indices, the relationship between 10 hPa polar vortex strength and the Antarctic Oscillation are analyzed as well. The results show that: (1) the polar region at 10 hPa in the Southern Hemisphere is controlled by anticyclone (cyclone) from Dec. to Jan. (from Mar. to Oct.), Feb. and Nov. are circulation transition seasons. (2) Intensity index (P) and area index (S) of anticy-clone (cyclone) in Jan. (Jul.) show a significant spike in the late 1970s, the anticyclone (cyclone) enhances (weakens) from ex-tremely weak (strong) oscillation to near the climatic mean before a spike, anticyclone tends to the mean state from very strong oscillation and cyclone oscillates in the weaker state after the spike. (3) There is significant interdecadal change for the anticyclone center in Jan., while markedly interannual variation for cyclone center in July. (4) The ozone anomalies can cause the interannual anomaly of the polar anticyclone at 10 hPa in the Southern Hemisphere in Jan. (positive correlation between them), but it is not related to the polar cyclone anomalies. (5) There is notable negative correlation between the polar vortex intensity index P and the Antarctic Oscillation index (AAOI), thus AAOI can be represented by P.     

大地电场观测各类干扰源的调研与分析

收集整理大地电场观测的各类干扰及变化原因,通过详尽的调研和相关分析研究,提出其常规干扰变化的识别方法,以及为提高大地电场观测资料的质量而采取的干扰抑制技术,并针对各类干扰源的机理,改进和完善现有的大地电场观测技术,提高资料的稳定性和可靠性。     

Study of a comprehensive assessment method of the environmental quality of soil in industrial and mining gathering areas

Industrial and mining activities have been recognized as major sources of heavy metal contamination in soil. Here, we developed a comprehensive assessment method for the soil environment in industrial and mining gathering areas based on the pressure–state–response model. Using this method, we assessed the environmental quality of soil in a typical industrial and mining gathering area in Tianjin City, China. The results are as follows: (1) The comprehensive environmental quality index of the soil in the study area was 0.532, which corresponds to an alert state and shows that the soil environment is generally poor. (2) The pressure, state, and response indexes were 0.609, 0.634, and 0.163, respectively, which suggests that the pressure in the soil environment of the study area is barely acceptable, and the state is merely passable. Furthermore, the response measures are not ideal. (3) The low response index scores indicate poor production processes, low pollutant treatment level, and unsatisfactory level of management by the enterprises in the study area. (4) The distribution of soil risks was found to be inseparably related to that of contamination sources and land use types. Furthermore, the distribution was uneven to a certain degree. Finally, we propose recommendations for the optimization, adjustment, and management of typical industrial and mining gathering areas with petrochemical, metallurgy, and other heavily polluting enterprises.     

Diet breadth and mortality patterns from Laoya Cave: A primary profile of MIS 3/2 hunting strategies in the Yunnan-Guizhou Plateau,southwest China

Laoya Cave is a long-term occupation site of Late Paleolithic humans in the Yunnan-Guizhou Plateau, southwest China, where abundant lithic, bone materials were recovered. Dating by the AMS technique showed a significant depositional process during marine isotope stage (MIS) 3/2. In this study, the species spectrum was presented from the perspective of zooarchaeology and the mortality profile of large Cervidae was examined to help increase our understanding of the subsistence strategy of local people dealing with climate and environmental changes. The main part of the diet was focused on large Cervidae, and the dominance of Ungulates indicates effective management of the cave and local fauna. On the other hand, the mortality profiles of large Cervidae varied correspondingly with climate change. The evidence indicates a specialized hunting strategy that was also flexible, depending on the prevailing climate and environment.     

库布齐沙漠南缘沙丘固定与活化过程中的形态演变

以1998-2014年5期库布齐沙漠南缘的遥感影像为主要数据源,结合野外调查分析了沙丘固定与活化过程中的形态演变,探讨了区域风况和降水等气象要素对沙丘固定与活化及形态演变的影响。结果表明：研究区沙丘随降水量的年际波动经历了固定-活化-再固定3个阶段。监测初期的片状流动沙丘演变为大型抛物线形沙丘并得以固定,固定的抛物线形沙丘以发育风蚀坑形式活化,进而形成多个抛物线形沙丘,最后这些沙丘又被植被固定,沙丘形态趋于更加复杂。但在此过程中,风的作用并不显著.研究区抛物线形沙丘既可起源于新月形沙丘或片状流沙,也可由风蚀坑发育而成,其中植被作为沙丘的重要组成部分,起着重要作用。同时发现在抛物线形沙丘移动过程中,当背风坡发育滑落面时,沙丘的移动最快。     

土壤样品中稀土元素的高分辨电感耦合等离子质谱分析及其不确定度的评定探讨

在敞开体系中,用HF、HNO_3和HClO_4溶解电感耦合等离子体质谱法同时测定土壤样品中的15种稀土元素.在高分辨等离子体质谱仪(Element2)上建立了土壤样品中稀土元素含量的ICP-MS分析方法,经土壤国家一级标准物质分析验证,结果与标准值相符,测定的15种稀土元素的相对标准偏差均小于10%,加标回收率为96.5%~114.7%.实验表明,该方法不但操作简便快速,而且具有灵敏度高、检出限低,重现性好等优点,举例说明了测量不确定度的评定程序.     

A general-purpose parallel raster processing programming library test application using a geographic cellular automata model

A general-purpose parallel raster processing programming library (pRPL) was developed and applied to speed up a commonly used cellular automaton model with known tractability limitations. The library is suitable for use by geographic information scientists with basic programming skills, but who lack knowledge and experience of parallel computing and programming. pRPL is a general-purpose programming library that provides generic support for raster processing, including local-scope, neighborhood-scope, regional-scope, and global-scope algorithms as long as they are parallelizable. The library also supports multilayer algorithms. Besides the standard data domain decomposition methods, pRPL provides a spatially adaptive quad-tree-based decomposition to produce more evenly distributed workloads among processors. Data parallelism and task parallelism are supported, with both static and dynamic load-balancing. By grouping processors, pRPL also supports data–task hybrid parallelism, i.e., data parallelism within a processor group and task parallelism among processor groups. pSLEUTH, a parallel version of a well-known cellular automata model for simulating urban land-use change (SLEUTH), was developed to demonstrate full utilization of the advanced features of pRPL. Experiments with real-world data sets were conducted and the performance of pSLEUTH measured. We conclude not only that pRPL greatly reduces the development complexity of implementing a parallel raster-processing algorithm, it also greatly reduces the computing time of computationally intensive raster-processing algorithms, as demonstrated with pSLEUTH.     

不动产登记证书"一证一码"应用研究与实现

分析了不动产交易、租赁过程中,不动产权证书查验存在无法实时查验等问题,将安全可靠的二维码技术引入到不动产权证书的制作中.通过移动互联网终端方便快捷地查验不动产权证书的登记信息,打破了时间和空间的限制,节约了办事成本,方便了办事群众,提高了政府效能.