青藏高原崇测冰芯在20世纪90年中气温变化记录

青藏高原崇测冰芯中稳定氧同位素（δ^180）记录表明：20世纪90年中该地区的气温在波动中呈上升趋势，可分为三个时期：1903～1940年为逐渐上升时期、1941～1970年为下降时期、1971～1992年为上升时期，第一时期波动较大，第二时期较平稳，第三时期波动最大；崇测冰芯δ^180值与塔里木盆地周围气象台站夏季气温记录存在显著的正相关关系，估计该地区20世纪90余年中夏季气温上升幅度约为1．2980℃。     

玉龙山温北川浅冰芯内气候环境信息的初步剖析

稳定同位素和离子分析结果表明,我国青藏高原东缘玉龙山温冰川的一支浅冰芯的大部分气候环境信息有良好的对应关系,可揭示近期若干年冰川净积累时期内的气候变化趋势和冰川的净积累量,且与当地实测资料相对应,该线冰芯的研究也揭示出冬夏季风和融水渗浸作用对冰芯气候记录的影响过程,表明温冰川气候环境信息的时间序列有限,温性冰川浅冰芯现代过程的分析为研究西南季风环流的动态变化提供了一个新的重要途径。     

氮氧稳定同位素技术用于水体中硝酸盐污染来源解析方面的研究进展

在总结不同硝酸盐潜在污染源的氮氧同位素特征值基础上,对可能使溯源结果产生影响的同化作用、反硝化作用以及硝化作用的判别方法进行了介绍.通过对文献中氮(δ(15N))氧(δ(18O))同位素特征值进行整理,发现随着时间以及地域的跨度增加,δ(15N)和δ(埔O)的特征值范围也不断增加,这导致特征值区间彼此重叠,从而并不利于溯源的进行.此外,通过δ(18O)与δ(15N)值可直观反映相关反应的发生,但是在某些情况下,同化作用与反硝化作用可能无法区分,而硝化作用产生的δ(18O)值也并非唯一.在总结氮氧稳定同位素技术解析硝酸盐污染来源的基础上,尝试对未来的发展方向提出建议.     

山东塔山黑松树轮稳定碳同位素与气候要素的响应

在山东塔山东坡采集黑松(Pinus thunbergii Parl)树芯样本,建立树轮稳定碳同位素年表,发现在数十年尺度上与工业革命以来大气稳定碳同位素比率降低的事实相吻合,但1976年之后树轮稳定碳同位素比率(δ13C)有逐渐上升的趋势,其原因可能是大气中CO2的积累效应导致了大气与海洋之间CO2交换的不稳定性.通过对样本δ13C序列校正提取高频序列后与气象站气象资料进行相关分析,发现树轮δ13C序列与温度呈正相关,与降水量和日照时数呈负相关,温度和降水以及日照时数对树轮δ13C的影响均存在一定的滞后效应,该地区树木生长的限制性气候因子比较复杂,可能受到多种气候因子的共同影响,在气候重建研究中应当慎重选择.     

萨拉乌苏河流域钙结核中碳氧同位素特征及古环境意义

通过对萨拉乌苏河流域酒坊台剖面中普遍发育的钙结核进行碳、氧同位素分析,结果显示各岩性组中同位素分布特征差异较大,无明显线性关系。利用钙结核中碳同位素值推算了不同岩性组中C_3和C_4植物的相对贡献量,结合孢粉数据,探讨了不同气候条件下植被演变情况,这与邻区的黄土高原研究成果基本吻合。同时,利用氧同位素和温度的经验公式,定量恢复了倒数第二次冰期-末次冰期的温度变化,其中末次间冰期表现为相对温暖的气候特征。总之,利用钙结核的碳氧同位素可作为定量恢复古温度、古植被的一种有效方式,但需要注意与其他指标进行综合对比分析。     

青藏高原过去2000年来气候环境变化研究

以现代过程研究为先导，以冰芯记录为手段，进行气候环境信息的挖掘，将影响环境的自然与人为因素进行整体研究，对环境长期演变过程中的重大自然事件和人为事件，特别是灾害事件进行剖析，从而提示青藏高原过去2000年来气候环境的变化特征与机理；阐明极低温环境下的微生物演化特征；揭示历史时期青藏高原大气温室气体含量变化的原因及其与气候变化之间的关系，并评价人类活动对环境的影响。     

京山地区方解石脉包裹体、同位素特征及古流体指示意义

通过流体包裹体,碳、氧、锶同位素资料分析及盆地模拟,对中扬子北缘京山地区古流体活动期次和流体来源进行研究。结果表明:包裹体均一温度指示京山地区存在4～5幕流体活动,确定地层裂缝中大规模流体活动时间为距今150～60 Ma;方解石脉体中捕获地层水盐度为12%～18%,具高盐度特征;奥陶系和三叠系灰岩围岩与方解石脉体的碳同位素δ13C值相当,方解石脉体沉淀时地层水的氧同位素δ18OSMOW值(5‰～12.5‰)高于海水,成岩流体为源于同层深部地层水;二叠系方解石脉体的δ13C、δ18O值较围岩偏负,锶同位素Sr87/Sr86值(0.707292～0.707735)与同期海水相当,成岩流体源于受有机质影响的本层地层水;中扬子北缘在距今150～60 Ma的构造挤压抬升作用中伴随的流体活动以同层内流动为主,穿层流动和地表水下渗影响微弱,古油气保存条件未遭受严重破坏。     

拉萨河铀同位素分布特征与环境指示意义

水体环境中铀及其同位素含量的变动对于区域生态环境的保护具有重要意义。目前,对于处于环境敏感区的拉萨河水体中铀及其同位素的研究鲜有报道。为了解拉萨河流域水体中铀及其同位素的分布特征,利用拉萨河中下游和堆龙曲支流2017年7月采集的16个采样点的水样,采用电感耦合等离子体质谱仪（ICP-MS）Element 2测量得到水样中的铀及同位素(238U、235U和234U)含量并进行分析。结果表明,拉萨河水体中铀浓度显著高于世界河流铀浓度均值,与青藏高原河水中铀浓度相当,略低于黄河干流河水中铀浓度。铀及其同位素与K+有同源性,与Mg2+及SO42-有异源性,而与其它水化学参数无显著相关关系。拉萨河水体中235U和238U具有很好的相关性,未发生显著的同位素分馏现象。拉萨河水体出现较高的(234U/238U)AR值,最主要原因是水体中234U的富集或者流失,在水-岩交换作用的影响下234U在α反冲作用下易于进入水体。羊八井附近采样点具有高铀浓度的特点,反映出其水体环境具有较好的氧化条件。     

Climatology of stable isotopes in Antarctic snow and ice: Current status and prospects

Stable isotopic composition in Antarctic snow and ice is commonly regarded as one of invaluable palaeoclimate proxies and plays a critically important role in reconstructing past climate change.In this paper we summarized the spatial distribution and the controlling factors of δD,δ18O,d-excess and 17O-excess in Antarctic snow and ice,and discussed their reliability and applicability as palaeoclimate proxies.Recent progress in the stable isotopic records from Antarctic deep ice cores was reviewed,and perspectives on bridging the current understanding gaps were suggested.     

Diversity of 16S rDNA and environmental factor influencing microorganisms in Malan ice core

The research on extrempholic microorganisms in glacial low-temperature environment receives more attention than ever before. Due to the successive chronological records in ice core, it is important to initiate microbiological studies on ice core samples. 23 samples from one ice core,drilled from central Qinghai-Tibetan Plateau, were analyzed.The number of total microorganisms and culturable microorganisms in different layers showed that it related with the content of dust in ice. It is suggested that the distribution of microorganisms in ice depends on the transportation of materials during glacier development. The bacteria diversity in Malan Glacier was analyzed by 16S rDNA sequencing methods, which showed that many sequences were similar to known psychrophilic bacteria.     

Diversity of 16S rDNA and environmental factor influncing microorganisms in Malan ice core

The research on extrempholic microorganisms in glacial low-temperature environment receives more attention than ever before. Due to the successive chronological records in ice core, it is important to initiate microbiological studies on ice core samples. 23 samples from one ice core, drilled from central Qinghai-Tibetan Plateau, were analyzed. The number of total microorganisms and culturable microorganisms in different layers showed that it related with the content of dust in ice. It is suggested that the distribution of microorganisms in ice depends on the transportation of materials during glacier development. The bacteria diversity in Malan Glacier was analyzed by 16S rDNA sequencing methods, which showed that many sequences were similar to known psychrophilic bacteria.     

Reconstructing past subsistence patterns on Zhongba Site using stable carbon and oxygen isotopes of fossil tooth enamel

The oxygen and carbon isotopic ratios in human and animal tooth enamel were measured to reconstruct the subsistence patterns on Zhongba Site between 2400 and 4200 aBP.The results indicate that human consumed chiefly C4 resources,such as millet,and the C3 plants,such as rice and wheat,constituted only a small fraction of the human diets,normally no more than 15%.There are significant differences in food sources between human and pig,and the percentages of C3 plants in pig diets were higher than those in human diets.But theδ13C values of pig partially overlap those of human,demonstrating some similarities in their food sources.The differences in water sources between human and pig are significant.There are significant differences in food and water sources between cattle and deer. This indicates that the two kinds of mammals subsisted in different niches.But theirδ13C values also partially overlap each other,suggesting some similarities in their food sources.There are both signifi- cant differences in meanδ13C andδ18O values between the omnivores,human and pig and the herbi- vores,cattle and deer,implying significant differences in food and water sources between the two categories.During the period the dietary habits of human had not changed,but the pig breeding strategies had changed,from breeding in house to breeding in confinement,and the proportion of C3 plants in pig food increased with time.The scope of human migration had been considerably large by the Warring States because of the development of productive forces.     

Climatic changes documented by stable isotopes of sedimentary carbonate in Lake Sugan, northeastern Tibetan Plateau of China, since 2 kaBP

Lake Sugan at the northern edge of the Qaidam Basin was selected as the research object. The temporal sequence of sedimentary cores retrieved from Lake Sugan since 2 kaBP was reconstructed using the ^210Pb, AMS 14C and conventional 14C dating methods. Carbon and oxygen isotopes of carbonate in the fine-grained lake sediments were analysed. Combined with the changes of 8180 values of surface water and air temperature observation data in the study area, it might be thought that the δ^18O value of the carbonate indicates effective moisture, and the changes in δ^13C values are related to annual freeze-up duration of the lake and indirectly indicate air temperature changes in winter half year. From the above, the sequence of climatic changes in the region since 2 kaBP was established. The climatic changes experienced five stages： Warm-dry climate during 0-190 AD： cold-dry climate during 190-580 AD; warm-dry climate during 580-1200 AD （MWP）; cold-wet climate during 1200-1880 AD （LIA）; cold-dry climate during 1880-1950 AD： and climate warming since 1950s. The air temperature changes in winter half year reflected by carbon isotope since 2 kaBP are in good agreement with the historical literature records and other geologic records, which shows that the climate changes recorded by the stable isotopes from Lake Sugan since 2 kaBP are of universal significance.     

溶解氧和气泡对食蚊鱼生存的影响

为了观测溶解氧对鱼生存的影响,在250mL^3次脱气水中加不同深度的金属网对食蚊鱼的生存状况进行比较,在真空脱气水和未脱气水的液面覆盖培养皿或覆盖液体石蜡时食蚊鱼的生存状况进比较,发现鱼不适于在溶解氧和气泡都很少的3次真空脱气水中生存．通过对比还发现,在相同的环境条件下,雄食蚊鱼的生命力普遍强于雌食蚊鱼;同时在微扰实验中发现,微量鱼水中含有溶解氧、气泡以及吸附了气泡的微米级颗粒,这些气体足以维持3条鱼存活4h以上．利用真空脱气方法观察鱼类的极限生存条件可能会成为一种全新的研究方法．