基于通用知识库的地理实体开放关系过滤方法

文本数据为地理知识服务提供了海量资源。面向文本数据的地理实体关系抽取是地理知识图谱构建的核心技术,直接影响地理知识推理与服务的质量。由于文本数据不可避免地含有噪声,从文本中抽取的地理实体关系需要质量评价和信息过滤。本文提出一种基于通用知识库的地理实体关系过滤方法,针对已抽取的地理实体关系从中筛选出高质量的结果：先利用“本体知识”、“事实知识”和“同义词知识”构建地理关系知识库,作为信息过滤的参照数据;再基于分布式向量表示模型度量已抽取的地理实体关系与参照数据之间的语义相似性,以提高地理知识图谱的丰度与鲜度。实验结果表明,相比业界流行的“Stanford OpenIE”工具,本文所提出的方法可将置信度区间[0, 0.2]和[0.8, 1]的MSE（Mean Square Error）从59.27%降至3.94%,AUC(Area Under the ROC Curve)从0.51提升至0.89。     

On the generation of coastline-following grids for ocean models—trade-off between orthogonality and alignment to coastlines

Regional ocean models usually utilize orthogonal curvilinear grids that are fit to the coastline of the modeled regions. While the orthogonality of the grid is required from the perspective of the numerical algorithms, the alignment to the irregular coastlines improves the characterization of the land-sea distribution and the ocean simulation. In this article, we carry out fractal analysis of two representative coastal regions and discuss the trade-offs between the orthogonality and coastline alignment during the grid generation of these regions. A new grid generation method based on Schwarz-Christoffel conformal mappings is proposed, with automatic coastal boundary retrieval algorithm that generates resolution dependent boundary for grid generation and alleviates the human efforts involved in traditional methods. We show that for the southeastern Pacific region, the coastline is smooth with low fractal dimension and there exists effective trade-off with a coastline boundary that adjusts to the desired grid resolution. On the contrary, there is no effective trade-off for southeast China seas where the coastline is of higher fractal dimension, and a coarser coastline boundary is recommended for better orthogonality with little loss in coastline alignment. Further numerical study of coastal trapped Kelvin waves for the typical regions demonstrate that the new coastline-fitting grids achieve smaller error in numerical dispersion and higher accuracy. Through analysis, we conclude that for grid generation for regional ocean modeling, modelers should bring into consideration of the multi-scale fractal characteristics of the coastline.     

造纸废水灌溉对芦苇湿地微生物的影响研究

为了解造纸废水灌溉对滨海芦苇湿地的影响,测定了几种灌溉条件下湿地基质中微生物数量、微生物量碳/总有机碳(MBC/ TOC)和土壤有效硫等指标.结果表明:造纸废水灌溉能显著提高基质中微生物数量和活性,且受季节影响较明显,一般在9月份最高;微生物数量在基质内垂直分布为上层>下层,特别是放线菌、真菌;反硝化细菌与土壤TN,纤维素分解菌与废水COD去除率,及MBC/TOC与基质呼吸强度相关性较好;硫酸盐还原细菌数量在10月份以后激增,使基质变黑,但对芦苇根系影响较小.废水灌溉能改良滨海盐碱土壤,促进退化生态系统的修复,但不同灌溉模式对微生物种群组成的影响不同,推荐采用间歇灌溉(w4)或低水深恒流灌溉(w1)模式.     

Using water isotopes and hydrogeochemical evidences to characterize groundwater age and recharge rate in the Zhangjiakou area,North China

Despite the increasing depletion of the groundwater at the Zhangjiakou aquifer system in the northwest of Beijing-Tianjin-Hebei region, little information is available on the hydrological process of groundwater in this region. In this study, we utilized water isotopes composition(δ~(18) O, δD and ~3 H) of groundwater, river and precipitation to identify the characteristics of hydrochemistry, groundwater age and recharge rates in different watersheds of the Zhangjiakou area. Results showed that the river water and groundwater could be characterized as HCO_3-Mg·Na, HCO_3·Cl-Na and HCO_3-Mg·Na, HCO_3·Cl-Na, HCO_3·Cl-Na·Mg types, respectively. The δD and δ~(18) O values in precipitation were linearly correlated, which is similar to the Global Meteorological Water Line(GMWL). Furthermore, the decreasing values of the δD and δ~(18) O from precipitation to surface water and groundwater indicate that groundwater is mainly recharged by atmospheric precipitation. In addition, the variation of 3 H concentration with depth suggests that groundwater shallower than around 100 m is generally modern water. In contrast, groundwater deeper around 100 m is a mixture of modern and old waters, which has longer residence times. Groundwater showed a relatively low tritium concentration in the confined aquifers, indicating the groundwater recharged might be relatively old groundwater of over 60 years. The flow velocity of the groundwater in the study area varied from 1.10 to 2.26 m/a, and the recharge rates ranged from 0.034 to 0.203 m/a. The obtained findings provide important insights into understanding the groundwater recharge sources and hydrochemistry in the Zhangjiakou area, in turn developing a sustainable groundwater management plan.     

松辽盆地G 12井晚白垩世青山口组沉积时期古湖泊学替代指标分析

总有机碳含量（TOC）、有机质碳稳定同位素（δ13C）、氢指数（HI）和有机质类型是进行古湖泊学研究的良好替代性指标,本研究以岩石热解分析数据和总有机碳测试数据为替代指标来综合反映松辽盆地青山口组二—三段晚期集水盆地的气候、湖泊生产力和湖泊底部水体环境等古湖泊学特征。指标显示：青山口组二—三段晚期集水盆地的古气候经历了温暖冷暖湿温暖而干燥干冷的演化过程;1933~1932m沉积时期,有机质以湖相为主,湖底为弱氧化环境,古湖泊初始生产力最高,其它阶段,有机质以陆源为主,虽然TOC含量高,但古湖泊初始生产力并不高;TOC值随深度减小而降低,δ13C值随深度变浅而偏正,而且δ13C值正向偏移量最大的时期晚于TOC值最高的时期;暖期时,TOC值较高,HI值较高,δ13C值偏负;冷期时,TOC值较低,HI值较低,δ13C值偏正。     

阿尔金断裂带康西瓦段晚第四纪以来的左旋滑移速率及其大地震复发周期的探讨

在高分辨率Ikonos卫星影像（1m分辨率）分析基础上,结合野外考察和定量测量,详细研究了阿尔金断裂带西段康西瓦段三十里营房地区晚第四纪以来的变形特征,在三十里营房东侧塔尔萨依吉勒尕河下游地区,断裂切割了一系列发育完好的冲积扇和阶地。6级不同阶地陡坎和邻近冲积扇面上冲沟的左旋位错量分别为251±4m,250±5m,198±4m,22±2m,12±1m和约6m。T2表面的放弃年龄约10.9±0.2ka（10Be）所限定的位错量22²00m,得到左旋滑移速率为2¹8mm/a;而T4阶地的最大累积位错可能达500m,暗示的左旋滑移速率约4⁵mm/a。最近一次大地震造成的最新地貌左旋水平位错量约6m,该地震同震地表破裂带沿喀拉喀什河谷延伸长达100km,估算为Mw7.4地震,约12m的位错量可能是公元975¹020年（AMS14C）以来最近两次大地震的累积同震地表位错,约6m的特征滑移量暗示该地段发生类似约Mw7.4地震的复发周期约370⁵00 a。这些结果表明,在青藏高原北缘,阿尔金断裂带西段为大型的左旋走滑断裂,它吸收了印度/欧亚大陆碰撞产生的较大部分应变,并使高原西部物质向东运移。     

长江三角洲各自然季节降水趋势

本文按不同自然季节分析长江三角洲各季降水的变化,根据降水异常年出现的规律,对公元2000年前各季的降水变化趋势作了展望。     

隐晶质石墨矿石的透射电镜观察

本文利用透射电镜观察了隐晶质石墨矿石的微观形态。结合X射线衍射和差热分析确定该石墨矿石除石墨碳外,尚含有少量的高岭石和水云母。     

Uplift of Northwest Margin of Tibetan Plateau: Indicated by Zircon LA ICP-MS U-Pb Dating of Conglomerate from Mazartagh, Tarim Basin

Radiometric age dating of detrital zircons is highly advantageous for analysis of the depositional environment and to identify source areas. Aiming at the uplift and denudation of the surrounding ranges, LA ICP-MS U-Pb analysis has been performed on zircon grains from a conglomerate collected at the Lower Pilocene of Mazartagh, which is in the center of the Tarim basin, Xinjinng (新疆), China. A wide range of ages mainly failing into three groups was yielded: 200-500, 800-1 100, and 1 800-2 000 Ma. Zircon features principally indicate magmatic origin. According to the comparison between the analyzed zircons with those from surrounding orogenic belts, the younger grains are mainly related to the west while the older ones are to the regions more eastward. The variations might imply the W-E propagation tectonic activation and uplift of the surrounding orogenic belts. The west segment uplifted and was denuded firstly, driven by the approximate W-E height difference, upon the denudation, transportation and deposition, acting as the source of young zircons analyzed. With the eastward spreading of tectonic movement, the segment more to the east rose, the meridional relief in creased rapidly and began to control the flow direction, then more zircons joined in the Pliocene in Mazartagh. It is difficult to definitely explain the source of grains with similar values to that from the Altyn Mountain region, more detailed data and chronological ages with higher precision will be helpful for making more credible conclusion.