Heavy metals status,transport mechanisms,sources, and factors affecting their mobility in Chinese agricultural soils

Heavy metals are the focus of much interest because of their environmental persistence, toxicity, and mobility in soils. Some of the Chinese soils have been contaminated with heavy metals due to expansion of mining industries, pesticides usage, and other anthropological activities, which made the agro-ecosystem to become contaminated. The objective of this review is to illuminate the current pollution status, sources of heavy metals, transport mechanisms, and the factors affecting their mobility in Chinese soils. The additional studies in the future will present on source identification and the heavy metal transport characteristics in soil.     

地震预报确定率、报准率和成功率的计算

本文提出一种评价地震预报意见的定量化方法。对于任一种预报意见的确定率、报准率和成功率均以数学公式表示。最后以1975～1984年我国年度地震趋势预报意见为例,进行了计算和分析。结果表明我国的地震中期预报水平还很低。     

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国土综合整治三维模型碎片加载优化与调度

国土整治作为一项国家战略,是解决社会经济发展过程中土地利用问题的重要手段,能有效促进国土空间优化和治理土地退化,对于实施乡村振兴战略和推进生态文明建设具有重大意义。随着我国工业化、城镇化的推进,生产、生活、生态之间矛盾日益凸显,国土整治在全国各地广泛开展,尤其是三维可视化技术的应用发展迅速。但对于国土整治业务而言,三维模型存在数据量大、数据复杂且碎片化程度高等特点,使得三维数据的存储管理和加载调度难度大,制约了其在国土整治中的应用。本文针对国土整治三维数据,提出了存储结构优化方法、三维模型碎片加载优化方法和三维模型调度优化方法,并开展了试验验证和应用示范,验证了本文提出的方法能够有效支撑国土整治中的三维可视化相关业务。     

Spatial heterogeneous response of land use and landscape functions to ecological restoration: the case of the Chinese loess hilly region

Ecological restorations over time may have profound effects on ecological and socio-economic systems. However, land-use changes and landscape functions that accompany ecological restorations can have spatial differentiations due to varied biophysical and socio-economic contexts. Therefore, these spatial differentiations caused by ecological restoration must be understood for better planning and management of restoration activities. The Baota District, with 576 villages in the center of the Chinese Loess Plateau, was selected as the study area because of its dramatic transition from cropland to grassland and shrubland from 1990 to 2010. Using the ArcGIS software and a k-means clustering analysis, an approach to identify types of land-use change patterns (TLCPs) at the village level was developed, and four TLCPs were delineated. The analysis indicated a general pattern of cropland decline by 21.6 %, but revealed significant spatial variations between villages in different TLCPs. Vegetation cover and soil retention, which are key proxies for landscape functions, increased by 22.70 and 108 %, respectively, from 2000 to 2010 with significant spatial heterogeneity. The Universal Soil Loss Equation was employed for the assessment of soil retention. The analysis of landscape metrics revealed a major trend of fragmentation and regularity on the county and village scale; however, spatial variations remained. Physical attributes were used to characterize different TLCPs, and notable differences were found. The spatial heterogeneous change in land use and landscape functions on the village scale may be useful for land use and ecological restoration management policy makers.     

精密水准与GNSS垂向形变关系研究——以天山构造带为例

以天山构造带区域为例,分别用精密水准和GNSS给出地壳形变垂直运动速率矢量图,对其差异及差异形成的原因进行深入分析和探讨,并基于优势互补原则,给出二者融合的形变图像。根据多年研究经验认为,该方法得到的垂直形变图在强震中长期预测中具有较为重要的应用价值。     

《中国大陆现代垂直形变图集的编制与资料整编》项目数据集

2015—2019年,由中国地震局第一监测中心牵头,自然资源部大地测量数据处理中心和武汉大学等单位共同完成科技部科技基础性工作重点专项,系统拯救、整编和共享20世纪50年代以来全国垂直形变测量数据,编制不同时空尺度的地壳垂直形变图,为强震中长期预测、地壳动力学研究、地形变灾害研究与防控及相关的国民经济建设服务。本文介绍中国大陆20世纪60年代—21世纪10年代不同时段1:400万和1:2 400万垂直形变图,其活动构造相关的地理要素、形变信息的清晰度更好,分辨率更高。还有典型沉降区垂直形变图、典型构造活动区（带）垂直形变图和强震同震形变图将在后续文章详细介绍。     

晋冀蒙地区的垂直形变特征

基于1998、2006和2013年3期水准复测资料,平差计算得到1998~2006年和2006~2013年的垂直形变速率及其垂直形变速率梯度。根据计算结果研究晋冀蒙地区的地壳垂直形变运动趋势以及主要断裂带的活动性,分析区域垂直形变速率和垂直形变速率梯度的演变。结果揭示出吕梁山地块后一时段上升速率增加、太行山地块由前一时段上升变为后一时段下降、盆地地带变化复杂的垂直形变态势。     

浙江临安4.2级地震特征及烈度调查

2017年4月12日,浙江省杭州市临安市发生4.2级地震,地震震中附近的潜川镇、河桥镇震感强烈,於潜镇、太阳镇、湍口镇等震感较为明显。在对震区地质构造、震源机制解资料分析的基础上,开展了烈度调查,并绘制了地震烈度图。本次地震震中烈度为Ⅴ度,面积22.6km2,烈度圈长轴方向北东向,与马金-乌镇断层走向一致。     

Mapping groundwater renewability using age data in the Baiyang alluvial fan,NW China

Hydrogeology Journal - Groundwater age has been used to map renewability of water resources within four groups: strong, partial, and rare renewability, and non-renewable. The Baiyang alluvial fan...