硼溶液蒸发过程中硼的挥发及硼同位素分馏

用蒸发实验研究了浓度为10-6级的硼在水和稀HCl溶液蒸发时的挥发度、同位素分馏和甘露醇的影响。结果表明，在溶液中有等摩尔的甘露醇和Cs都存在的条件下，硼才能在蒸发时和蒸干后保持定量回收；硼在不加入甘露醇或Cs的稀HCl溶液中蒸发时也能定量回收，但是不能蒸干；若要蒸干．必须加入等摩尔的甘露醇，才能保持硼的定量回收。蒸发液和残留液的同位素测定表明，11B仇先从近中性和酸性溶液的蒸发中贫化。此结果对于硼需要预富集的过程是非常重要的。     

新西兰韦斯特兰省南阿尔卑斯山铜金热液体系

新西兰的南阿尔卑斯山是一个现在还在上升的山脉,在阿尔比尼断层附近显示出地热异常,阿尔比尼断层是澳大利亚板块和太平洋板块的分界线。在这个上升带中出现了强烈的热液运动,这种热液运动导致了石英脉中的金属矿化。金的矿化限于绿片岩相的岩石中,而阿尔比尼断层附近的角闪岩相岩石中年轻的石英脉中则富含铜。地下上升的热液和下渗的大气降水溶液之间的相互作用控制着这个复杂的热液体系中金属的搬运活动和沉淀过程。变质热液已与石墨片岩围岩相平衡,并且相对被还原,大气水的渗入和混合增加了氧的活动性而降低了硫的活动性。大气水在下渗过程中被氧化,但温度上升,溶解了一些铜。当这种液体变成还原状态时,溶解的铜便沉淀出来。因此,这个热液体系的中间部分,铜的含量是逐渐增加的,特别是在阿尔比尼断层附近的强烈破碎渗透性较好的岩石中。     

地球系统科学、全球变化与可持续发展

针对当今全球性环境危机问题,阐述了地球系统科学、全球变化与可持续发展的关系,提出只有积极地进行全球变化研究,才能很好地协调自然与社会的持续稳定发展。     

Dynamics of phosphorus and nitrogen through litter fall and decomposition in a tropical mangrove forest

Distribution, dynamics and mass budget of phosphorus and nitrogen in a red mangrove forest were studied in the Potengi mangrove forest in northern Brazil (lat. 5 degrees 42' and 5 degrees 53'S, long. 35 degrees 5' and 35 degrees 25'W). Tidal hydrology, net primary productivity, leaf litter decomposition rate and standing stock of leaf litter in a red mangrove forest were measured. The results showed that the main reservoir for total P and total N was the sediment with 309 kg ha(-1) and 4619 kg ha(-1) (77% and 95% of the total P and N content in the mangrove forest), respectively, for the two elements. Total P and total N in Rhizophora mangle trees accounted for 145+/-14 kg ha(-1) and 216+/-23 kg ha(-1) (23% and 5% of the total P and N in the mangrove forest). The estimated average export rates for P and N through leaf litter are 0.5 kg ha(-1)yr(-1) and 1.6 kg ha(-1)yr(-1) respectively. Our measurements support previous results in concluding that mangrove forests efficiently retain P and N.     

Heterogeneities in glaciofluvial deposits using an example from new hampshire

The strong influence of subsurface heterogeneity on contaminant migration and in situ remediation calls for an improved understanding of its origins and more efficient methods of characterization. Accordingly, an outcrop study of physical and chemical heterogeneity was conducted in a glaciofluvial deposit in Deerfield, New Hampshire, in order to uncover processes controlling the spatial variation of sediment properties and evaluate the extent to which geologic information can be used to characterize the observed variation. The results indicate that physical and chemical properties at the Deerfield site have distinctly different spatial correlation structures. Lithologic facies explain 31% to 60% of the variation in permeability, dithionite citrate (DC)-extractable manganese, and DC-extractable aluminum. Lithofacies bounding surfaces do not separate regions of significantly different DC-extractable iron; instead, 49% of its variation is explained by sediment color. Color also accounts for 34% of the variation in DC-extractable aluminum and 60% of the variation in DC-extractable manganese. Strong relationships with sediment facies and/or color enable detailed mapping of permeability, extractable iron, and extractable manganese. Differences in the geometries of iron and manganese enrichment, petrographic observations, and scanning electron microscope analyses indicate that (hydr)oxide grain coatings originated from the postdepositional weathering of biotite and garnet, coupled with local, redox-driven redistribution of the liberated iron and manganese. The findings suggest that lithofacies and color information can aid the characterization and modeling of heterogeneity at similar carbon-poor glaciofluvial sites.     

参加气候变化国际科学大会总结

“气候变化：全球风险、挑战与决策”国际科学大会于2009年3月10～12日在丹麦首都哥本哈根召开,该会南国际大学研究联盟（IARU）主办,该联盟包括了目际上10所研究型大学,北京大学也列其中,旨在通过研讨交流,对目前气候变化领域国际最新科学进展进行梳理,