黄河凌汛检测系统分析

根据清洁水体、浑浊水体和冰体在不同波段的反射率不同,运用C语言编写黄河凌汛检测系统程序,将清洁水体、浑浊水体和冰体检测出来,运用GIS的地图控件计算出清洁水体、浑浊水体和冰体面积以及它们的中心经纬度,以实现对黄河凌汛的动态检测。     

黄河梁山段近46年凌情变化特征分析

梁山地处黄河下游河道,冬、春两季因上下游河水结冰时间不同,常形成冰水齐下、冰凌壅塞和水位上涨,造成凌汛洪水灾害。选取黄河梁山孙口水文站和县气象局1964~2009年黄河梁山段的冰情和气温资料,分析了近46年来该河段凌汛、封冻和岸冰厚度的变化趋势与气温变化的关系。分析表明：该河段的凌汛期为11月下旬到翌年3月中旬,凌汛、河道封冻和岸冰厚度都呈减弱趋势;凌汛与近期冬季平均气温呈变暖趋势呈十分明显的反相关;在一定程度上,可以根据气温变化预测凌汛的强弱,以避免灾害的发生。     

挥发性有机物监控系统与黄河水质自动监测系统的集成

为了进一步扩展黄河水质自动监测站的自动监测项目,提升水质自动监测能力,引进、开发了适用于黄河水体的挥发性有机污染物在线监测系统,并对挥发性有机物在线监测设备CMS5000与自动站现有监测设备的集成和应用改造进行了研究。     

挥发性有机物监控系统与黄河水质自动监测系统的集成

为了进一步扩展黄河水质自动监测站的自动监测项目,提升水质自动监测能力,引进、开发了适用于黄河水体的挥发性有机污染物在线监测系统,并对挥发性有机物在线监测设备CMS5000与自动站现有监测设备的集成和应用改造进行了研究.     

乌梁素海冰封期水体富营养化特征分析

以内蒙古乌梁素海为研究对象,对其在冰封过程中富营养化指标在冰体和水体中的浓度及分布特征及其在乌梁素海的空间变异性进行分析,得出冰封期乌梁素海富营养化状况。其中,乌梁素海水体中的富营养化指标含量均大于对应的冰体中的含量,主要指标COD、总氮、总磷在水体中的含量均值分别是冰体中含量均值的1.65、1.61和1.78倍;水体中的营养盐变异性明显小于冰体中的。说明低温冷冻过程对水体中污染物有一定浓缩效应,并对此进行了解释,以期为乌梁素海富营养化治理提出研究方向。     

养殖水体在线自动监测系统的总体构架及特点

养殖水体在线自动监测系统是以分析设备为核心,以互联网为基础的水质在线监测系统,通过监测终端采集数据,基于遥感器和GPS进行数据传输,监控中心通过处理收集的有效数据信息分析水质参数变化规律,为人工、半自动化和自动化养殖提供基础数据,进而完善管理,提高水产品的产量和品质。为养殖水体在线自动监测系统在水产养殖中的推广运用提供参考,介绍了养殖水体在线自动监测系统的监测目标、总体构架及特点。     

准格尔旗2022年生态变化及黄河凌汛分析

分析了准格尔旗2022年和2021年年度气候条件、生态变化、重点工矿区遥感和黄河鄂尔多斯段开河进度,得出以下结论：(1)准格尔旗2022年1—10月气温略高,地下水位前期受到降水量偏少影响,水位偏低,汛期开始至今,水位明显上涨,地下水位数值缩小;(2)2022年8月初至9月初准格尔旗植被覆盖度达到全年峰值,受降水影响,全旗植被覆盖度在汛期结束后,总体优于历年及去年同期;(3)准格尔旗境内水镜湖水体面积为25.7万m²,较2021年同期缩小0.9万m²;准格尔旗境内库布齐沙漠面积为53.07 km²,约占全旗0.69%,较2021年同期沙漠面积相比偏大8.46 km²;(4)黄河凌汛遥感监测方面,开河期间黄河准格尔旗段共发现清沟25条,总面积约为6.65 km²,清沟范围在逐步扩大。     

气温对黄河阿拉善盟段凌汛的影响分析

利用阿拉善盟2008~2017年10 a凌汛期水文和气温序列资料,研究了阿拉善盟凌汛期特征、凌汛灾害发生主要时段,黄河封河、开河集中期与日平均气温之间的关系。结果表明:阿拉善盟凌汛特征为封开河时序相反,受强冷空气影响较大;凌汛灾害主要发生在封河和开河期间;日平均气温正负转化日期与封、开河期有对应关系,首次流凌平均日期在12月6日,最早11月20日,最晚12月15日;进入首封河期平均日期12月25日,最早12月17日,最晚1月12日;全线封冻平均日期1月2日,最早12月24日,最晚1月24日,黄河段首次开河集中在2月28日至3月14日,全线开河集中在2月27日至3月8日,每年封(开)河集中时段,72 h日平均气温变化幅度可作为凌汛灾害预警防御重要指标。     

水体铜对黄河鲤肝胰脏中铜蓝蛋白表达量的影响

同时用0、0.21、0.30、0.43、0.60、0.81 mg/L Cu2+刺激黄河鲤,于作用2、4、6、8、10 d后采集肝胰脏取样,应用半定量RT-PCR法监测肝胰脏中铜蓝蛋白mRNA表达量的变化,来探究水体铜对黄河鲤肝胰脏铜蓝蛋白表达量的影响。结果表明:黄河鲤在不同的水体铜浓度刺激下,肝胰脏中CP mRNA的表达量对Cu2+的刺激呈现时间依赖性以及剂量依存性,随着时间变化CP mRNA表达量存在先升后降的趋势;并且CP mRNA表达量可达到一个最高峰,但达到峰值的时间不尽相同。     

基于GF-1号遥感影像的微小水体信息提取研究——以岔口流域为例

针对不同因素影响,山区微小水体提取效果不佳的问题,选用2016年9月1日GF-1号卫星遥感影像,运用NDWI、SWI决策树、SVM分类3种不同方法对位于黄土高原沟壑区的山西省岔口流域的微小水体进行了提取,并对提取效果进行视觉对比与精度验证。结果表明,相比中低分辨率遥感影像,高分辨率遥感影像对于山区微小水体的提取结果更好,精度更高,可运用GF-1号影像进行流域水体的监测、提取;影响流域水体提取的主要因素是亮色地物(主要为建筑物)和阴影;NDWI、SWI决策树、SVM分类3种方法中,NDWI方式提取的水体信息较弱,SWI决策树与SVM分类法精度较高,但SWI决策树法消除了建筑物、亮色地物的影响,并较明显地区分了阴影与水体,因此更适用于流域微小水体的提取。     

额尔古纳河河道冰下水位自动监测系统

根据对额尔古纳河流域冰下水位监测的需求,本文利用基于空气、冰与水电阻特性差异的冰水情检测原理,设计了一种全新的适合额尔古纳河河道的冰下水位自动测报系统,整个系统由现场冰下水位数据采集和数据处理中心两部分组成,通过对冰水情信号的采集和传输实现了对河道冰下水位、冰厚值的定点连续自动测报。经过试验证明该系统具有工作状态良好、自动化程度高、信息传送准确和监测连续等优点。试验数据为相关部门提供了第一手的界河冰下水位的数据情况。     

An active subglacial water system in West Antarctica mapped from space

Satellite laser altimeter elevation profiles from 2003 to 2006 collected over the lower parts of Whillans and Mercer ice streams, West Antarctica, reveal 14 regions of temporally varying elevation, which we interpret as the surface expression of subglacial water movement. Vertical motion and spatial extent of two of the largest regions are confirmed by satellite image differencing. A major, previously unknown subglacial lake near the grounding line of Whillans Ice Stream is observed to drain 2.0 cubic kilometers of water into the ocean over approximately 3 years, while elsewhere a similar volume of water is being stored subglacially. These observations reveal a wide spread, dynamic subglacial water system that may exert an important control on ice flow and mass balance.     

More than 200 meters of lake ice above subglacial Lake Vostok, Antarctica

Isotope studies show that the Vostok ice core consists of ice refrozen from Lake Vostok water, from 3539 meters below the surface of the Antarctic ice sheet to its bottom at about 3750 meters. Additional evidence comes from the total gas content, crystal size, and electrical conductivity of the ice. The Vostok site is a likely place for water freezing at the lake-ice interface, because this interface occurs at a higher level here than anywhere else above the lake. Isotopic data suggest that subglacial Lake Vostok is an open system with an efficient circulation of water that was formed during periods that were slightly warmer than those of the past 420,000 years. Lake ice recovered by deep drilling is of interest for preliminary investigations of lake chemistry and bedrock properties and for the search for indigenous lake microorganisms. This latter aspect is of potential importance for the exploration of icy planets and moons.     

Grain size-sensitive creep in ice II

Rheological experiments on fine-grained water ice II at low strain rates reveal a creep mechanism that dominates at conditions of low stress. Using cryogenic scanning electron microscopy, we observed that a change in stress exponent from 5 to 2.5 correlates strongly with a decrease in grain size from about 40 to 6 micrometers. The grain size-sensitive creep of ice II demonstrated here plausibly dominates plastic strain at the low-stress conditions in the interior of medium- to large-sized icy moons of the outer solar system.     

冷冻浓缩过程冰晶生长的相场法模拟

以水为原料,利用相场模型从微观上对冰晶生长机制进行模拟,结果表明:随着过冷时间的延长,冰晶的分枝逐渐发达;随着过冷度的增高,冰晶的分枝也逐渐发达.表明控制过冷时间和过冷度是冷冻浓缩过程中降低冰晶夹带率的重要措施.     

Antarctic krill under sea ice: elevated abundance in a narrow band just south of ice edge

We surveyed Antarctic krill (Euphausia superba) under sea ice using the autonomous underwater vehicle Autosub-2. Krill were concentrated within a band under ice between 1 and 13 kilometers south of the ice edge. Within this band, krill densities were fivefold greater than that of open water. The under-ice environment has long been considered an important habitat for krill, but sampling difficulties have previously prevented direct observations under ice over the scale necessary for robust krill density estimation. Autosub-2 enabled us to make continuous high-resolution measurements of krill density under ice reaching 27 kilometers beyond the ice edge.     

Rutherford backscattering to study the near-surface region of volatile liquids and solids

Here we describe the use of Rutherford backscattering spectrometry (RBS) to measure quantitative in situ elemental profiles with high depth resolution, online and nondestructively, in volatile substances (liquid and frozen acids, ice). Samples for analysis are held in a chamber with controlled temperature and partial pressures designed to match conditions for aerosols in Earth's atmosphere. This technique is demonstrated in studies of water solubility in sulfuric acid, hydrochloric acid (HCl) on ice surfaces, the formation of a HCl-hexahydrate surface layer on evaporating HCl-doped ice, and the diffusion of water through this layer.     

乌梁素海冰封期浮游植物群落特征与环境因子CCA分析

冰封期湖泊水体及冰体内水质发生变化,直接影响水产健康养殖发展。基于2016年1月15日乌梁素海冰封期浮游植物及水质监测结果,分析冰封期湖泊浮游植物物种组成、密度及多样性指数空间动态,利用典范对应分析法(CCA)揭示浮游植物物种与环境因子关系。结果表明,冰下水体共鉴定出浮游植物7门32属37种,浮游植物群落组成呈硅藻—绿藻型;冰体中共检出7门34属60种,浮游植物群落组成以硅藻为主。冰体中Margalef丰富度指数(D)、Shannon-Wiener多样性指数(H)、Pielou均匀度指数(J)变化趋势一致。3种指数综合显示乌梁素海冰封期浮游植物群落结构相对稳定。水体共发现优势种10种,冰体中优势种共14种。CCA排序显示,TP为影响乌梁素海冰下水体浮游植物群落分布最重要环境因子。冰层中NH4+、TP、TN等环境因子复杂分布对浮游植物群落在冰层中分布影响较大。研究结果为开展寒旱区冰封期水体及冰体中水质与浮游植物群落特征关系方面研究奠定基础。     

Ultrafast electron crystallography of interfacial water

We report direct determination of the structures and dynamics of interfacial water on a hydrophilic surface with atomic-scale resolution using ultrafast electron crystallography. On the nanometer scale, we observed the coexistence of ordered surface water and crystallite-like ice structures, evident in the superposition of Bragg spots and Debye-Scherrer rings. The structures were determined to be dominantly cubic, but each undergoes different dynamics after the ultrafast substrate temperature jump. From changes in local bond distances (OH.O and O.O) with time, we elucidated the structural changes in the far-from-equilibrium regime at short times and near-equilibration at long times.