准噶尔盆地东部双井子地区上石炭统泥岩地球化学特征及其地质意义

准噶尔盆地东部石钱滩凹陷石炭系巴塔玛依内山组火山岩之后发育一套连续稳定的碎屑岩沉积。笔者等通过XRD、主微量元素分析等手段针对其中的细粒沉积岩开展元素地球化学研究,其结果对恢复准东地区晚石炭世源区风化特征、古气候、判断其源岩性质及源区构造背景具有重要意义。研究表明,巴山组—石钱滩组泥岩具有低石英含量特点,其中巴山组泥岩黏土含量稍高,而石钱滩组泥岩中长石含量高,两者黏土成份均为蒙脱石（>99%）,反映了干燥、寒冷的气候特征且沉积介质长期为碱性;CIA结果显示巴山组—石钱滩组时期经历了中等—弱化学风化作用,并具有干湿交替气候变化特征;主微量元素及相关判别图解显示巴山组—石钱滩组泥岩的源岩多以偏中性的长英质火山岩为主,少量中基性及少量偏酸性的火山岩物源,并且多数为未分异的弧;泥岩的地球化学特征反映了沉积物源区构造背景主要为大陆岛弧背景,结合石钱滩组碎屑锆石峰值年龄及主要物源区分析认为,野马泉地体与其南部的准噶尔地体东北缘于335 Ma左右开始由俯冲转变为碰撞造山。     

琼北玄武岩建造区域岩石—土壤体系化学元素垂向分布规律

土壤由岩石风化而来,岩石—土壤是一个密切联系的体系,是地球系统科学中与人类关系最为密切的一部分。为调查研究地质建造单元岩石—土壤体系（简称：岩土体系）中的物质组成演化特征,我们必须选择原地风化的残积物出露区域来完成土壤垂向剖面采样。本文以海南岛区域生态地质背景调查项目的资料数据为基础,科学阐述了残积物剖面的确定方法,并依据琼北玄武岩垂向剖面地球化学数据,总结出如下结论：垂向剖面SiO2含量呈现出土壤表层A层和岩石的高,土壤B、C层含量低的“凹”字型特征,与Al2O3含量变化趋势相反（“凸”字型）,两个代表性组分存在明显的负相关性,其他组分根据其亲和性,与该两种组分协同变化,部分受表层活动影响较大的元素,例如有机质、I等部分微量元素,则不具有该规律,土壤表层（A、B层）与深层（C层）、岩石中差别通常较大。     

Eco-environmental problems and effective utilization of water resources in the Kashi Plain, western Terim Basin, China

Since ancient times, water resources, mainly from melting snow in the high mountains, have nourished a large area of an oasis in the Kashi Plain in the western Terim Basin, China. In the last half-century, however, the rapid growth of population and the overexploitation of water, soil, and biological resources have led to drought, salinization, and desertification in the area, and consequently have hindered the development of sustainable agriculture. In this study, groundwater reservoirs with sustainable water supplies equivalent to 44.65×10⁸ m³/year were identified, which has made it possible to implement several projects in the area to improve the ecological and agricultural environment. Three strategies are proposed for the integrated development and management of both surface-water and groundwater resources in the area. Electronic Publication     

Climatology of the meteorological factors associated with haze events over northern China and their potential response to the Quasi-Biannual Oscillation

An upswing in haze weather during autumn and winter has been observed over North and Northeast China in recent years, imposing adverse impacts upon local socioeconomic development and human health. However, such an increase in the occurrence of haze events and its association with natural climate variability and climate change are not well understood. To investigate the climatology of the meteorological factors associated with haze events and their natural variability, this study uses a meteorological pollution index called PLAM (Parameter Linking Air-quality to Meteorological conditions) and ERA-Interim reanalysis data. The results suggest that high PLAM values tend to occur over southern parts of northern China, implying the weather conditions over this area are favorable for the occurrence of haze weather. For the period 1979–2014, the regional mean PLAM shows an overall increase across Beijing, Tianjin, and Hebei Province, and parts of Shanxi Province. Also, a periodicity of 28–34 months is found in the temporal variation of PLAM, which implies a potential association of PLAM with the stratospheric Quasi-Biannual Oscillation (QBO). By using the QBO index during the autumn and winter seasons in the preceding year, an increase in PLAM is found for the westerly phases of the QBO, relative to the easterly phases. An upper-tropospheric warming is also found in the westerly phases, which can induce a stable stratification that favors the increase in PLAM across the midlatitudes. The modulations of large-scale environmental factors, including moist static stability, vertical velocity, and temperature advection, also act to enhance PLAM in the westerly phases. However, the baroclinic term of moist potential vorticity at 700 hPa tends to decrease over the south, and an increase in low-level ascent is found over the north. These factors can reduce PLAM and possibly limit the statistical significance of the increased PLAM in the westerly phases of the QBO.     

亚热带河口区对虾养殖池塘浮游植物初级生产力变化

浮游植物初级生产力是评估水产养殖系统结构与功能的基础环节,对渔业资源的开发与管理具有重要意义.于2018年5-10月,采用黑白瓶法对闽江河口区的3个南美白对虾养殖塘(Pond Ⅰ、Pond Ⅱ和Pond Ⅲ)水体浮游植物初级生产力进行了原位监测,初步研究了初级生产力在池塘间的差异性及其时间变化特征.结果显示,养殖期间养...     

活动造山带地区河流阶地与下切速率及其时空分布样式

河流下切带动区域地貌的演化,因此河流下切速率及其时空分布样式是解析构造、地表过程和气候变化之间广泛相互作用的关键切入点之一。根据阶地的保存状况,利用河流阶地的累积下切量和下切时间可以直接测得千年到百万年时间尺度的下切速率。鉴于此河流下切速率是链接不同时间和空间尺度上地貌侵蚀速率的关键所在,并具有较精细的时空分辨率。计算河流下切速率时,累积下切量上限是阶地基座的拔河高度,下界最优选择是低级阶地基座,而累积下切时间的最佳约束是尽量靠近阶地基座的冲洪积物的沉积时间;运用河流下切速率获得岩石抬升速率和区域构造变形量时,通常假定区域地貌处于均衡状态,河流下切速率代表着岩石抬升速率。但是由于气候变化,河流下切过程具有较强的时空不稳定性,导致这些假设经常失效。此外,河流加积和下切的转换与第四纪冰期-间冰期的变化并不一定存在时间上的一一对应关系,这可能是由于河流裂点的溯源迁移以及河流对气候变化的响应方式与强度存在差异。因此,实际工作中需要多方面获得不同时空尺度和分辨率的构造变形、气候变化以及地表过程的基本信息,借助地貌数值模拟程序,定量解析构造、气候和地表过程之间的广泛而复杂的相互作用。

     

2005年11月26日九江—瑞昌5.7级地震浅析

对赣北及邻区2014年以来的地震条带及视应力进行了分析。结果表明：江西丰城—安徽蒙城2014年10月—2015年6月快速形成M_L≥3.0地震条带,地震条带及周边地区的视应力均值为0.49 MPa,条带上的地震视应力高于条带以西地区,低于条带以东的江苏北部地区。2009年4月以来江西瑞昌—南黄海出现M_L≥4.0地震条带,条带及周边地区的视应力均值为1.72 MPa,条带上的视应力水平高于条带外。视应力总体呈现随震级增大而增大的特点。     

基于栖息地指数的西北太平洋日本鲭渔情预报模型构建

根据2014−2017年5−11月西北太平洋公海灯光围网日本鲭(Scomber japonicus)生产数据,结合同期的环境遥感数据,分别基于捕捞量和作业次数,构建日本鲭栖息地适宜性指数(Habitat Suitability Index,HSI)模型。选取海表水温、海面高度异常和叶绿素a浓度,采用一元指数回归拟合,建立各个环境变量的适应性指数模型,并利用线性规划方法确定各环境因子的权重,从而提高日本鲭HSI模型对渔场的预报精度。利用2018年5−11月的实际捕捞数据对模型进行预报准确率验证,在基于渔获量和作业次数构建的HSI模型中,HSI大于0.7的海域,渔获量平均占比分别为77.29%、76.79%,这表明基于不同权重环境因子的HSI模型能够较好地预测西北太平洋公海日本鲭中心渔场。