极地冰雪环境地球化学指标及其指示意义

极地冰雪中可以反映气候环境的环境地球化学指标主要是可溶性杂质和不可溶性微粒。可溶性杂质主要包括H+、Na+、Mg2 +、Ca2 +、NH4+、Cl- 、NO3- 、SO42 - 、CH3SO3- 等。本文在概述冰雪中的这些化学杂质的来源影响因素和时空分布特征的基础上 ,概述了冰雪中NO3- 沉积的主要来源 (即闪电作用和高层大气光化学作用产生的含氮化合物等 )及其影响因素 (包括太阳活动、火山活动、超新星活动、核爆炸试验和沉积后的蒸发及迁移作用等 ) ,SO42 - 的主要来源 (即海洋生物释放和火山喷发等 )、影响因素 (包括源区温度、ENSO事件及海冰面积等 )和它们的时空变化特点 ;讨论了南、北极地区冰雪中微粒沉积的主要源区和变化特征。。     

北极Svalbard群岛Longyearbyen地区雪坑主要阴、阳离子特征研究

北极Ｓｖａｌｂａｒｄ群岛Ｌｏｎｇｙｅａｒｂｙｅｎ地区３条冰川８个雪坑样品的分析结果表明,该地区冰川表层雪中海盐离子Ｃｌ－和Ｎａ＋占主导地位,其浓度远高于其它离子,而陆源Ｃａ２＋在雪坑秋季污化层中浓度远远高于其它层位,可作为雪坑定年中秋季层位的标志。在季节变化上,海盐离子和ＳＯ２－４、ＮＯ－３在春季和夏季表现为高值,这与冬春季节北大西洋风暴和中纬度人类污染物远距离传输到北极有关,也与夏季局地海洋性气团、大气中氧化作用、光电作用和清除速率有关。同全球的边远地区格陵兰、南极和青藏高原比较,Ｌｏｎｇｙｅａｒｂｙｅｎ地区雪中离子浓度水平较高,特别是海盐离子浓度远高于其它地区。     

Characteristics of ion concentrations in snowpits in Longyearbyen, Svalbard, Arctic

１ＩｎｔｒｏｄｕｃｔｉｏｎＳｔｕｄｉｅｓｏｎｃｈｅｍｉｃａｌｃｈａｒａｃｔｅｒｉｓｔｉｃｓｉｎｓｎｏｗｐｉｔａｒｅｖｅｒｙｉｍｐｏｒｔａｎｔｉｎｒｅｓｅａｒｃｈｏｆｍｏｄｅｒｎｐｒｏｃｅｓｅｓｉｎｓｎｏｗａｎｄｉｃｅ,ｗｈｉｃｈｉｓｂａｓｉｃｃｏｎｔ...     

Spatial variations of Pb,As, and Cu in surface snow along the transect from the Zhongshan Station to Dome A,East Antarctica

The spatial distributions of lead, arsenic, and copper(Pb, As, and Cu, respectively) in surface snow along the transect from the Zhongshan Station to Dome A, East Antarctica, are presented. The mean concentrations of Pb, As, and Cu are1.04±1.56 pg/g, 0.39±0.08 pg/g, and 11.2±14.4 pg/g, respectively. It is estimated that anthropogenic contributions are dominant for Pb, As, and Cu. Spatially, Pb concentrations show an exponentially decreasing trend from the coast inland, while a moderate decreasing trend is observed for Cu concentrations in the coastal area(below 2,000 m above sea level(a.s.l.)).In the intermediate area(2,000–3,000 m a.s.l.), the concentrations and enrichment factors of all these elements show high variability due to the complicated characteristics of climate and environment. On the inland plateau(above 3,000 m a.s.l.),the high concentrations of As and Pb are induced by high deposition efficiency, the existence of polar stratospheric precipitation, and the different fraction deposition to East Antarctica. The extremely high concentrations with maximum values of9.59 pg/g and 69.9 pg/g for Pb and Cu, respectively, are suggested to result mainly from local human activities at the station. Our results suggest that source, transport pathway, and deposition pattern, rather than distance from the coast or altitude, lead to the spatial distributions of Pb, As, and Cu; and it is further confirmed by spatial variations of the three metals deposited over the whole continent of Antarctica.     

CONCENTRATION CHARACTERISTICS OF SOLUBLE IMPURITIES IN THE SURFACE SNOW OF COLLINS ICE CAP, KING GEORGE ISLAND, ANTARCTICA

Measurements carried out for the upper 10m firn/ice obtained at the main dome of Collins Ice Cap, King George Island, Antarctica revealed the direct relation of soluble impurities of snow mass to the composition of atmosphere aerosols. It was indicated that sea salt source dominates the atmosphere aerosol around Collins Ice Cap. The simultaneous variation shown by the concentration profiles of Na~+, K~+, Mg~(2+), Ca~(2+), SO_4~(2-), CI~-, Br~- and very close EF values (≈1) suggested their common marine source and similar deposition process. Besides the possible surface contamination,NH_4~+varied uniformly along deeper part of the core in concentration, which could be considered as background value of ammonium. A satisfactory explanation for NO_3~- concentration profile has not reached at present.     

南极拉斯曼丘陵湖泊水化学特征

本文介绍南极拉斯曼丘陵湖泊水化学特征。对１３个湖泊的调查和统计分析表明，湖水以Ｎａ＋和Ｃｌ－为主要优势离子，不含有ＣＯ３２－离子，营养物质（Ｎ、Ｐ、ＳｉＯ２）在湖水中普遍偏低，而且湖水和雪样无机氮组分均以ＮＨ４＋为主，水化学类型比较单一，都属氯化物Ｎａ＋型贫营养水体。Ｎａ＋、Ｃｌ－、ＳＯ４２－的高浓度，特别是Ｂｉｇ湖、莫愁湖和Ｈｅａｒｔ湖水中离子含量明显的高，指示拉斯曼丘陵地区的降水来源以海洋气团为主，并受海洋环境影响强烈。微量元素分布在０．０１～２．０μｇ／ｌ之间，接近于水圈这些元素的浓度值。     

中国第26次南极科学考察航线上空水溶性气溶胶化学成分特征研究

利用我国第26次南极考察航线上所采集到的气溶胶样品,分析了各水溶性离子组分的浓度、组成及存在形式.采用多种数理统计方法对各离子成分特征及其来源进行了分析.结果显示:阴阳离子总和接近于1,表明航线上空主要阴阳离子具有海洋气溶胶的代表性;CI-、Na<'+>、SO<'2-><,4>、NO<'-><,3>、Mg<'2+>是航...     

The concentration variation features of sea salt ions and non sea salt ions in a firn core recovered from Princess Elizabeth Land, East Antarctica

A 51.85 m firn core drilled in Princess Elizabeth Land, Antarctica, during the 1996-1997 Chinese First Antarctic Inland Expedition, has been measured for δ 18 O and major ions. Based on the high quality data of the seasonal variations of major ions, the firn core was dated with errors within ±3 years. The 51.85 m firn core record extends for 251 years (A. D. 1745-1996). The results of the glaciochemistry data of the firn core show that the mean concentrations of Cl -, Na + and Mg 2+ are similar to those reported from other coastal areas in East Antarctica. However, mean concentrations of Ca 2+ are much higher than those reported from other regions, this anomaly phenomenon may be related to the strong local terrestrial sources. It is found that the variations of three kinds of sea salt ions (Cl -, Na + and Mg 2+ ) in the past 150 years show very similarly rising trends, which may be the results the Southern Hemisphere warming in the past century.     

南极洲纳尔逊冰帽雪层剖面和冰川化学特征

Nelson冰帽位于南极洲边缘地区,周围海洋环绕。雪层剖面受融水干扰,但综合分析后仍能观察到季节变化的轮廓。结合雪层剖面和杂质成分及浓度分析,推知这里以局地海洋气团降水为主,冬季降水中杂质含量高于夏季,平均杂质含量远远高于内陆,人类活动等对环境的影响已在雪层中留下痕迹。但NO_3~-的沉积速率在整个西南极洲相差不显著,大气圈作用是控制NO_3~-沉积的主要因素。     

The difference of atmospheric chemical loadings shown by electrical conductivity of snow and ice between Antarctica, Arctic and Qinghai Tibetan Plateau

１ＩｎｔｒｏｄｕｃｔｉｏｎＥｌｅｃｔｒｉｃａｌｃｏｎｄｕｃｔｉｖｉｔｙｉｎｐｒｅｃｉｐｉｔａｔｉｏｎｒｅｆｌｅｃｔｓｔｈｅｌｏａｄｉｎｇｏｆｉｏｎｓｉｎｐｒｅｃｉｐｉｔａｔｉｏｎ,ｔｈｕｓｄｉｓｐｌａｙｓｔｈｅｃｈｅｍｉｃａｌｏｕｔｌｉｎｅｏｆｔｈｅ...     

松嫩平原西部盐沼湿地水环境化学特征

松嫩平原西部盐沼湿地水环境碱化程度高,水中的pH值普遍高于8.0,多数为苏打钠型水。在对本区盐沼基本水环境化学特征阐述的基础上,通过对水化学的基本变量CO₃^2-、HCO₃^2-、Cl^-、Ca²⁺、Mg²⁺、SO₄^2-、Na⁺和派生变量(Cl^-+SO₄^2-)/HCO₃^2-及Na⁺/(Ca²⁺ Mg²⁺)等的相关分析,得出各水化学变量之间的相关关系,并以pH值为分类基础得到了判别函数和判别区域图,对区域盐沼湿地水环境化学特征的研究方法作出了有意义的尝试。     

中亚天山托木尔峰地区青冰滩72号冰川雪坑化学特征及其环境指示意义

基于2008年7月天山托木尔峰地区青冰滩72号冰川雪坑实测资料,探讨其冰川雪坑离子化学特征及环境指示意义。研究发现,Ca2+、Mg2+是青冰滩72号冰川雪坑中主要阳离子;雪坑中阳离子浓度顺序为:Ca2+>Mg2+>Na+>K+>NH4+,其中,Mg2+、K+和Ca2+主要反映长距离沙尘源物质传输情况;Cl-和Na+则一半以上来源于海盐;青冰滩72号冰川NO3-浓度高于天山地区含量平均值。     

Physical properties and stratigraphy of surface snow in western Dronning Maud Land, Antarctica

Information about the spatial variations of snow properties and of annual accumulation on ice sheets is important if we are to understand the results obtained from ice cores, satellite remote sensing data and changes in climate patterns. The layer structure and spatial variations of physical properties of surface snow in western Dronning Maud Land were analysed during the austral summers 1999/2000, 2000/01 and 2003/04 in five different snow zones. The measurements were performed in shallow (1–2 m) snow pits along a transect extending 350 km from the seaward edge of the ice shelf to the polar plateau. These pits covered at least the last annual accumulation and ranged in elevation from near sea level to 2500 m a.s.l. The ع⁸O values and accumulation rates had a good linear correlation with the distance from the coast. The mean accumulation on the ice shelf was 312±28 mm water equivalent (w.e.); in the coastal region it was 215±43 mm w.e. and on the polar plateau it was 92±25 mm w.e. The mean annual conductivity and grain size values decreased exponentially with increasing distance from the ice edge, by 48%/100 km and 18%/100 km respectively. The mean grain size varied between 1.5 and 1.8 mm. Depth hoar layers were a common phenomenon, especially under thin ice crusts, and were associated with low dielectric constant values.     

下辽河平原和辽东半岛海岸带晚更新世以来的海侵

本文根据钻孔资料、¹⁴C测年数据、微体古生物及孢粉组合特征,讨论了研究区晚更新世以来海侵的次数、规模、时间以及岸线变化。     

东南极普里兹湾海冰面地磁考察

中国第九次南极考察期间在中山站北部普里兹湾中面积约１３２ｋｍ２的测区内进行了地磁测量，为日后的南极内陆考察作前期准备。磁测资料表明，这里有一个宽约５－８ｋｍ、走向ＮＷ的磁异常，其幅度达５００ｎＴ。磁异常可能是由深成岩浆的侵入体或富含磁铁矿的地质体引起的，磁源物体的埋深在海冰面以下０．３－２．０ｋｍ。考察实践证明：只要经过充分准备，利用普里兹湾冬季冰封的有利条件，开展大范围的海冰面地球物理考察，在技术上是可行的。     

天山乌鲁木齐河源1号冰川大气气溶胶和新雪中可溶性离子关系研究

在2007年4月、8月和10月三个时段内,分昼夜采集了23个气溶胶样品和7个新降雪样品,对样品中的可溶性离子进行了分析。结果表明,乌鲁木齐河源1号冰川(以下简称1号冰川)春、夏、秋三个季节气溶胶平均载量为86.22 neq/m³,分析显示1号冰川存在NH₄HSO₄和(NH₄)₂SO₄气溶胶,并有少量NH₄NO₃气溶胶存在。气溶胶和新雪样品中可溶性离子成分变化趋势相似,气溶胶浓度升高,新雪样品的浓度也会有所升高,反之亦然。气溶胶和新雪中Ca²⁺、Mg²⁺、Na⁺、Cl^-、K⁺的相关性很好,说明雪中这些离子的浓度基本能反映大气中的状况;对气相和颗粒相并存的NH₄⁺和NO₃^-来说,雪中的离子浓度和大气中的离子浓度不相关。     

The spatial and seasonal distributions of air-transport origins to the Antarctic based on 5-day backward trajectory analysis

Transport of moisture-bearing air to the Antarctic is one of the important factors that control the mass balance of the ice sheet. Here, we investigate the distribution of air-parcel transport using a backward trajectory analysis over the entire Antarctic ice sheet, based on whether the air parcel was located inside or outside of Antarctica at 5 days before arrival. At this time, we considered the air from outside Antarctica to be moisture rich. Oceanic air was found to dominate in West Antarctica throughout the year, whereas air from inland was more prominently distributed around East Antarctica, especially in summer. In East Antarctica, there was a significant seasonal variation: air from inland dominated in summer, while air of oceanic origin dominated in winter. The distribution of air parcels that came from oceanic/inland sources was similar to the accumulation map (based on satellite data), which indicates that oceanic air parcels could be a substitute for moisture transport to the Antarctic. To determine the future impacts of climate change (e.g., sea level rise), more precise predictions of the variations in the surface mass balance will be required. Our results contribute towards the improved understanding of the spatial distributions of accumulation and aerosols found in Antarctic snow and ice cores.     

表生作用条件下硼酸盐矿床的形成问题

沉积硼酸盐矿床在自然界分布相当广泛 ,主要见于南、北美和我国青藏高原的盐湖中、美国和土耳其某些第三纪沉积盆地中 ,以及欧洲某些古代海相盐矿床中。为了研究其形成问题 ,从 70年代开始 ,我们利用青藏高原盐湖卤水和泉水进行了许多模拟实验工作。从 40～ 5 0个样品中获得了大量钠硼酸盐、纳钙硼酸盐、镁硼酸盐和含氯化镁的镁硼酸盐复盐。这对于阐明表生作用条件下硼酸盐矿床的形成是非常重要的。实验和研究结果证明 :1)与地热和火山活动有关的水体是硼酸盐矿床形成的物质来源 ;2 )硼酸盐矿床可形成于Ｎａ、Ｋ、Ｍｇ//Ｃｌ、ＳＯ4 ·Ｈ2 Ｏ和Ｎａ、Ｋ//Ｃｌ、ＳＯ4 、ＨＣＯ3、ＣＯ3·Ｈ2 Ｏ不同水盐平衡体系的不同富硼水体中 (盐度 :1 2 7～ 41 4% ,Ｂ2 Ｏ3含量 :0 0 5～ 2 97% ) ;3 )硼酸盐矿床通常形成于稳定平衡条件下 ,而不是介稳平衡条件下 (蒸发过程中 ) ;4)低温条件有利于硼酸盐自水体中析出 ;5 )硼酸盐矿床的形成与水体的化学类型、ｐＨ值和硼含量有密切关系 ;6)我们实验中所获的硼酸盐反映了天然硼酸盐矿床形成的原始条件。不仅揭示了大陆盐湖硼酸盐矿床的形成 ,也揭示了古代海相盐矿床硼酸盐的成因。     

腾格里沙漠区盐湖物质成分研究

腾格里沙漠面积广阔 ,区内分布着数十个盐湖 ,盐湖面积大的为十余平方千米 ,小的仅为 0 .0 18km2 。盐湖卤水主要为湖表卤水 ,其矿化度较高 ,大部分盐湖卤水含盐量已达饱和 ,因而进入了自析盐阶段。盐湖卤水化学成分以 Na+ 、K+ 、Cl-、SO4 2 -、HCO3 -、CO3 2 -为主 ,占卤水总含盐量的 99% ,卤水中还有 B2 O3 、L i、I、Br等微量元素。盐湖盐类沉积有碳酸盐类、硫酸盐类和氯化物型盐类、主要盐类矿物为芒硝、钾芒硝、天然碱、泡碱、碳钾钠矾、石盐等。盐湖粘土矿物组合以蒙脱石的普遍存在为特征 ,含有少量的伊利石和水云母。     

A confirmed earthquake in continental Antarctica

Summary. An earthquake of magnitude ( M _b) 4.5 has been located by the International Seismological Centre, near 81°S, 37°E in the continental platform of east Antarctica, about 1200 km from the coast of Dronning Maud Land, and 500 km from the Pole of Inaccessibility. The event was found by the Centre's 'search' procedure, which is undertaken with a deliberate delay of about two years. It occurred on 1982 November 4, and its position is well determined from five stations in Antarctica, and four farther afield. This is the first earthquake definitely located in the interior of the Antarctic continent, although there have been some earlier less well established claims, and other earthquakes have occurred near the coast, or associated with areas of volcanism or ice movement.