固城湖晚全新世以来的孢粉组合及环境变迁

本文依据固城湖GD钻孔系统的孢粉分析资料,将井深6.3m岩心所做的孢粉图式,结合~(14)C测年,从下面上分为8个孢粉组合带,进而论述了4000年来该区的植被发展和气候的4次冷暖交替的变化。4次冷期约为3.0—2.5KaB.P.2.0—1.5KaB.P.、1.0—0.8KaB.P.和0.4Ka以来。此外,还根据沉积物中的硅藻分析、有机质δ~(13)C值、有机碳含量及历史记载等资料,侧重讨论了气候及人类活动对湖泊环境演变的影响。     

近三十年天津市地热大规模开发热储动态特征研究

天津是我国较早大规模开发深层地热的地区之一,经过30多年的持续开采回灌,对深部热储特征有无影响,是否引起了资源枯竭、水质恶化以及热储温度下降等环境问题,一直是社会关注的焦点。本文系统收集了1992年以来天津市地热开发过程中的不同热储层热水开发利用量、回灌量、水位、水质、水温等近30年的时间序列监测资料,通过垂向及横向对比,对地热持续开发30年来天津市不同地区不同热储层的热水动态特征进行了分析。结果表明,天津市各热储层地热流体的主要化学组分基本稳定,多年来无明显变化,地热采灌系统尾水回灌不会从根本上改变地热流体的原始化学特征,但深大断裂作为热流通道引起的顶托补给,会对上层热储水质造成一定的影响;随着近年来天津市回灌工作力度不断加大,大部分热储水位下降幅度减缓或出现回升,热储的温度没有明显的升高或降低的趋势,但回灌井热储段经过非供暖期的恢复无法达到最初的温度,呈逐年下降趋势。未来持续采灌条件下,回灌井筒的“冷堆积”及采灌井的优化调配应是重点关注的问题。     

用监控机房雷击情况及架空线路雷击参数分析SPD多级防护的重要性

通过对阳泉市道路商品开发公司西收费站机房雷击事故的调查分析，以及对阳泉地区架空明线雷击参数的简要分析，强调机房安装SPD多级防护的重要性，以尽可能最大限度减少雷电灾害。     

中国气候与环境演变评估（Ⅰ）：中国气候与环境变化及未来趋势

近百年来,全球气候正经历着一次以变暖为主要特征的显著变化,全球气候与环境的重大变化对中国的气候与环境演变也产生了重大影响。来自气候、环境、海洋和经济社会科学等领域的百余位专家和学者对中国气候与环境的演变及其对自然生态系统和社会经济部门的影响进行了评估,在此基础上,提出了适应和减缓气候变化的对策。本文主要阐述在全球气候变化背景下中国气候与环境的演变,并对未来气候变化的趋势做出了预测。     

T213数值预报释用技术的研究

通常情况下副高控制下的稳定层能抑制对流的发展,天气晴好。但有极少数的局地强降水,是发生在大尺度高压脊附近。本文通过对2004年8月10日阳泉地区在副高控制下的暴雨天气从环流背景、物理量特征等方面,进行了综合分析和探讨,结果表明,当低层水汽充足,局地大气具有潜在不稳定能量和适当的触发条件时,在500hPa副热带高压内部也会出现中尺度暴雨云团,产生强降水。     

MM5中尺度模式及其微物理过程

非静力平衡模式MM5，除掉了静力平衡假定，可以将模式格距减小到10km以下。由于在物理过程参数化、网格嵌套、资料四维同化等方面也有许多改进，大大改善了模式性能，扩展了其应用范围。应用MM5对我国中尺度天气系统的大量个例模拟研究及业务预报试验表明，MM5可以较好地模拟预报我国的中小尺度天气系统，适合制作乡镇短期天气要素预报。     

太湖14000年来古环境演化的湖泊记录

Two sediment cores, one 396 cm long from west Taihu Lake, another 246 cm long from east Taihu Lake, are interpreted from the analysis of their magnetic susceptibility, total organic carbon, total nitrogen, total pigments, organic carbon isotope, hydrogen index, saturated hydrocarbons, ¹⁴C dating and surficial sediment conditions. The west Taihu Lake core is the longest one studied in this lake so far, and has provided us the most complete environmental and climatic information for this lake. The results from the west Taihu lake core indicate that Taihu Lake has undergone the following stages:from ca.14 300 to 13 300 aB.P. Taihu Lake was in low lake-level, and there existed exposed features from the proxies reflecting arid paleoclimate. From ca.13 300 to 12 400 aB.P. an arid transitional stages occurred with a slightly warmer and wetter climate. From ca. 12 400 to 10 900 aB.P. a period of large climatic fluctuation occurred and from 10900-10 000 aB.P. a warm period developed with deep water and strongly reducing sediments. During ca.10 000-7 200aB.P., a cool transitional period alternating with a warm climate occurred. It was warm and wet during 7 200-5 700aB.P.; some proxies changed violently in 5 050aB.P., reflecting obvious changes in material source and a probable interruption of sedimentation. The east Taihu Lake history from ca. 6 550 to 6 450 aBP, the climate was cold and dry, and gradually turned warm and wet in ca. 6 450-6 050 aBP. It was warm and wet in ca. 6 050-5 800 aBP and had a cold tendency in 5 800-ca. 5 000 aBP. An abrupt change occurred at ca. 5 000 aBP, and the lake sediment in the uppmost part was disturbed by wave action indicating shallow water conditions.     

若尔盖盆地兴措湖沉积记录揭示的近代气候与环境

依据湖泊沉积记录进行古气候环境要素定量的是过去全球变化研究的重要内容,本文通过若尔盖盆地兴措湖近代湖泊沉积特征、沉积物总有机碳及其同位素指标分析,并与器测气象资料进行比较,对兴措湖泊近代湖泊沉积物中有机碳及其同位素指标所代表的气候环境信息进行了定量研究,在此基础上,建立了兴措湖沉积物总有机碳及其同位素记录与对应的降水和气温间的函数关系,为定量恢复该区长尺度历史时期古气候环境特征提供了基础。     

不同有机酸对矿物溶解的动力学实验研究

用石英、微斜长石和方解石混合颗粒模拟碎屑组分分别与不同有机酸水溶液进行溶蚀实验,以比较储集层内不同矿物在含低分子量有机酸地层水中溶解的速率,并试图探讨矿物溶蚀的微观机理。结果表明：①所有矿物颗粒都发生了不同程度的溶解,表现为颗粒失重,溶液中SiO2和金属阳离子含量增加,pH值上升。②优先溶解的是方解石,其次是硅酸盐矿物。③温度增加,硅酸盐矿物在水中的溶解度明显增加,而方解石的溶解度基本不变。④由于不同有机酸与二氧化硅和金属阳离子生成的络合物稳定性不同,因此,在不同有机酸水溶液中,矿物的溶蚀速率有较大差别。多官能团有机酸的水溶液中,不同矿物有更大的溶解;但在含有丰富Ca2＋的草酸水溶液中,由于矿物颗粒表面难溶草酸钙的沉淀,方解石的溶解变得更加困难。⑤多官能团有机酸与SiO2形成的多环螯合物由于完全取代了硅氧四面体的氧原子,在水中具有高度稳定性,可能有助于(铝)硅酸盐的溶蚀和硅元素的迁移     

Constraints on water chemistry by chemical weathering in the Lake Qinghai catchment, northeastern Tibetan Plateau (China): clues from Sr and its isotopic geochemistry

Lake water, river water, and groundwater from the Lake Qinghai catchment in the northeastern Tibetan Plateau, China have been analyzed and the results demonstrate that the chemical components and ⁸⁷Sr/⁸⁶Sr ratios of the waters are strictly constrained by the age and rock types of the tributaries, especially for groundwater. Dissolved ions in the Lake Qinghai catchment are derived from carbonate weathering and part from silicate sources. The chemistry of Buha River water, the largest tributary within the catchment, underlain by the late Paleozoic marine limestone and sandstones, constrains carbonate-dominated compositions of the lake water, being buffered by the waters from the other tributaries and probably by groundwater. The variation of ⁸⁷Sr/⁸⁶Sr ratios with cation concentrations places constraint on the Sr-isotopic compositions of the main subcatchments surrounding Lake Qinghai. The relative significance of river-water sources from different tributaries (possibly groundwater as well) in controlling the Sr distribution in Lake Qinghai provides the potential to link the influence of hydrological processes to past biological and physical parameters in the lake. The potential role of groundwater input in the water budget and chemistry of the lake emphasizes the need to further understand hydrogeological processes within the Lake Qinghai system.