陆表自然和人文要素相互作用——“全球变化及应对”重点专项研究进展

在国家重点研发计划支持下,项目提出了陆表不均一性检测和订正的新方法,解决了渐变型不均一性检测和订正的难题,构建了中国地表太阳辐射、气温、地温、风速和降水等参数均一化站点和格点数据集,修订了关于中国地表风速变化趋势、增温格局及其形成机制的结论。融合多源数据,构建并验证了千米级、流域级或县域级的电厂、人口、生物质能、取水量、氮排放、二氧化碳排放等影响自然系统的关键人文要素历史和未来预估数据集。构建了未来关键人文要素情景,研制了碳中和目标下甲烷和氧化亚氮排放情景和用于驱动全球模式的未来情景,预估了中国碳中和战略的实施对全球变暖的减缓作用,发现中国碳中和对远期和中期全球变暖的减缓作用显著。给出了中国各省份水体氮排放安全阈值及超越时间,阐明了中国粮食产量与氮施肥的关系,提出了在保障粮食安全的前提下减少水体氮排放的有效途径,指出重构城乡养分循环体系是同时保障粮食安全和恢复水质的必要途径。发现全球饱和水汽压差的年际变化与大气二氧化碳浓度上升速率的年际变化显著相关,阐明了饱和水汽压差变化在调控生态系统生产力中的重要角色以及多因素耦合作用在生态系统生产力变化中的复杂影响。建议更全面细致地评估中国各种碳中...     

Migration and speciation transformation mechanisms of mercury in undercurrent zones of the Tongguan gold mining area,Shaanxi Loess Plateau and impact on the environment

In order to study the migration and transformation mechanism of Hg content and occurrence form in subsurface flow zone of gold mining area in Loess Plateau and its influence on water environment, the field in-situ infiltration test and laboratory test were carried out in three typical sections of river-side loess, alluvial and proluvial strata in Tongguan gold mining area of Shaanxi Province, and the following results were obtained: (1) The source of Hg in subsurface flow zone is mainly caused by mineral processing activities; (2) the subsurface flow zone in the study area is in alkaline environment, and the residual state, iron and manganese oxidation state, strong organic state and humic acid state of mercury in loess are equally divided in dry and oxidizing environment; mercury in river alluvial or diluvial strata is mainly concentrated in silt, tailings and clayey silt soil layer, and mercury has certain stability, and the form of mercury in loess is easier to transform than the other two media; (3) under the flooding condition, most of mercury is trapped in the silt layer in the undercurrent zone where the sand and silt layers alternate with each other and the river water and groundwater are disjointed, and the migration capacity of mercury is far less than that of loess layer and alluvial layer with close hydraulic connection; (4) infiltration at the flood level accelerates the migration of pollutants to the ground; (5) the soil in the undercurrent zone is overloaded and has seriously exceeded the standard. Although the groundwater monitoring results are safe this time, relevant enterprises or departments should continue to pay attention to improving the gold extraction process, especially vigorously rectify the small workshops for illegal gold extraction and the substandard discharge of the three wastes, and intensify efforts to solve the geological environmental problems of mines left over from history. At present, the occurrence form of mercury in the undercurrent zone is relatively stable, but the water and soil layers have been polluted. The risk of disjointed groundwater pollution can not be ignored while giving priority to the treatment of loess and river alluvial landform areas with close hydraulic links. The research results will provide a scientific basis for water conservancy departments to groundwater prevention and control in water-deficient areas of the Loess Plateau.     

蜀南地区下三叠统飞仙关组沉积相

蜀南地区飞仙关组的沉积相类型主要有浑水陆棚相与清水陆棚相,东部两者交替发育,中西部则主要为浑水陆棚相。浑水陆棚相以半局限海亚相为主,包括三个微相;清水陆棚相可分为颗粒滩、滩间、潮坪和内缘斜坡等四个亚相,包括若干微相。飞一段全区为清水陆棚相;飞二段全区均为浑水陆棚亚相的泥质半局限海微相;飞三段,西部为浑水陆棚相,东部为清水陆棚相,其间发育灰泥质半局限海微相;飞四段基本为泥质半局限海微相。飞一时,区内中部有一近南北向的台内凹槽,沿凹槽边缘鲕粒滩较发育。研究区以西的康滇古陆和龙门山岛链与华蓥山断裂带控制着区内沉积相展布,当康滇古陆和龙门山岛链构造活跃时全区发育浑水陆棚,华蓥山断裂带活动时东部发育清水陆棚;当康滇古陆、龙门山岛链与华蓥山断裂带构造的活动性都较低时,全区以清水陆棚为主。     

基于仿射变换的数字影像内定向的误差控制分析

数字化摄影测量生产中的误差来源众多,尤其是系统误差常常很突出。针对这个问题,首先深入分析了附有未知数的仿射变换控制模型参数的误差估计,然后利用误差传播定律和误差综合原理,推导出了任意非检控点经仿射变换后输出数据精度的计算公式,并通过数值分析从理论上验证了用四个角框标进行数字影像内定向是最佳误差控制方案。     

Impacts of TRMM SRR assimilation on the numerical prediction of tropical cyclone

1 IntroductionObservation of the tropical rainfall is crucial forthe research on tropical weather and climate. Nu-merous studies have shown that the ingestion of rain-fall data into a numerical model can have considera-ble impacts on simulation results(Kr…     

中哈俄阿尔泰稀有金属矿床时空分布、成因及成矿规律

中哈俄阿尔泰发育许多大型—超大型稀有金属矿床,是世界著名的稀有金属成矿省.该成矿省可分为3个稀有金属成矿带,自西南向东北依次为哈萨克斯坦Kalba-Narym、中国阿尔泰和俄罗斯山区阿尔泰等.这3个成矿带稀有金属矿床以伟晶岩型为主,但伟晶岩与花岗岩关系及其伟晶岩成因不一致:在哈萨克斯坦Kalba-Narym成矿带和俄罗...     

拟建胶莱运河可能产生的地质灾害与环境问题

概述了拟建胶莱运河工程附近主要发育的海水入侵、风暴潮、水灾和旱灾、地震砂土液化、水资源缺乏、地表水污染等地质灾害与环境问题,探讨了拟建工程可能引发或加剧风暴潮、海水入侵、地下水环境变化、土地盐渍化和岸坡稳定性等地质灾害或环境问题。对工程建设前的预研究内容提出了建议,以探讨问题的解决方法或措施。     

大深度载人潜水器低速大漂角模糊滑模航向控制研究

通过模型试验测量大深度载人潜水器低速大漂角运动时所受到的非线性水动力。基于一种新的模糊滑模控制策略,为潜水器设计了鲁棒航向控制器。在不同的漂角子区间内分别设计局部镇定的滑模控制器,然后通过Takagi-Sugeno模糊推理系统将它们光滑连接,得到模糊滑模控制。仿真计算结果充分显示了该控制策略的有效性。     

中国沿海常见蓝子鱼形态比较研究

对中国沿海常见蓝子鱼科鱼类的外部形态、呼吸器官、感觉器官、消化器官、骨骼系统等形态特征进行了比较研究。发现不同种蓝子鱼在体形、鳃耙、耳石、肝脏、牙齿、头骨等特征上存在一定差异,但是种间差异较小,从而推断本科鱼类分化较缓慢。     

流场散度的误差估计

按照误差传递原理,推导出流场散度的误差估计式,并将其应用于赤道中东太平洋上升流区域水平散度误差的估计。应用结果表明:赤道中东太平洋上升流区多年平均流场的散度稳定,平均散度约为3.0×10-7s-1;和通常采用的误差估计公式相比,该估计公式降低了散度误差,从而提高了散度的可信度。