全球冰川融水生物活性铁研究进展  

A review of bioactive iron in global glacier meltwater

作　　者：杨瑞 李向应 杨船洋 易童 苏茜蕊 闫玉强 YANG Rui;LI Xiangying;YANG Chuanyang;YI Tong;SU Xirui;YAN Yuqiang(College of Urban and Environmental Sciences,Northwest University,Xi’an 710127,China;Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity,Xi’an 710127,China;Anhui Urban Construction Design Institute Corp,Ltd.,Hefei 230071,China)

机构地区：[1]西北大学城市与环境学院,陕西西安710127 [2]陕西省地表系统与环境承载力重点实验室,陕西西安710127 [3]安徽省城建设计研究总院股份有限公司,安徽合肥230071

出　　处：《冰川冻土》2024年第3期795-805,共11页Journal of Glaciology and Geocryology

基　　金：国家自然科学基金项目(42171123,41671053)资助。

摘　　要：铁(Fe)是生物生命活动必需的营养元素,也是高营养盐低叶绿素海域浮游生物生长的重要限制因子。随着冰川加速消融,融水冲刷和冰岩磨蚀作用增强,化学风化速率升高,促使更多Fe元素从基岩转移到融水中。冰川向下游输送了大量生物活性Fe,影响水生生态系统初级生产力,进而影响碳循环并反馈气候系统演化。冰川融水中Fe生物地球化学循环已成为冰冻圈与全球变化领域的研究热点。尽管已经取得一些进展,但在时间和空间尺度上还存在较大不足,尚不清楚融水中Fe的空间变化和输移过程。通过回顾冰川融水Fe浓度和通量及其稳定同位素比率(δ^(56)Fe)的研究成果,分析了Fe及δ^(56)Fe的空间变化特征,量化了区域及全球冰川Fe释放速率,发现融水中Fe浓度具有季节性变化,且受基岩岩性和径流量等因素影响,而融水的Fe通量主要受流量影响。未来应加强冰川融水Fe时空演变过程研究,解析其来源和输移规律,关注可被生物利用的Fe,全面深入认识冰川环境中Fe循环过程及其生态和气候效应。Iron(Fe)is an essential nutrient element for biological activities,which can promote the formation of chlorophyll a,and is an important limiting factor for plankton growth in high nutrient salt and low chlorophyll sea area.With the accelerated ablation of glaciers,the erosion of melt water and the abrasion of ice and rock are enhanced,and the rate of chemical weathering is increased,which promotes more Fe elements to transfer from bedrock to melt water.Glaciers transport a large amount of bioactive Fe downstream,which will affect the pri-mary productivity of aquatic ecosystems,thereby affecting the carbon cycle and feedback the evolution of the cli-mate system.The biogeochemical cycle of Fe in glacial meltwater is a hot topic in cryospheric hydrochemistry.At present,some progress has been made in the study of Fe in glacial meltwater,but there are still great deficien-cies in the time and spatial scale.The spatial variation and transport process of Fe in meltwater are still unclear.By reviewing the research results of Fe concentration and flux and its stable isotope ratio(δ^(56)Fe)in glacial melt-water,the concentrations of soluble iron(sFe),colloidal/nanoparticle iron(cnFe),dissolved iron(dFe)and particulate iron(pFe)in glacial meltwater and their spatiotemporal variations ofδ^(56)Fe were analyzed at water-shed,regional and global scales.The release rates of various forms of iron from regional and global glaciers were quantified.The annual dFe flux of the glacier is about(403±737)Gg and the production is about(7151±13061)kg·km-2.Concentration of Fe in the meltwater is seasonal,and is affected by factors such as bedrock li-thology and runoff.The amount of iron output from glaciers is mainly affected by the flow rate.In the future,we should strengthen the research on the temporal and spatial evolution of glacier meltwater iron,analyze its source and transport law by usingδ^(56)Fe,pay attention to the bioavailable iron,and comprehensively understand the Fe cycle process and its ecological and climatic effects

关 键 词：铁(Fe) 铁稳定同位素比率(δ56Fe) 融水 冰川 

分 类 号：P343.6[天文地球—水文科学] O614.811[天文地球—地球物理学]