The effect of forest vegetation on the formation of mercury accumulation signals in lake sediments

森林植被对湖泊沉积物汞积累信号形成的影响

基本信息

批准号：
286806412
负责人：
Professor Dr. Harald Biester, Ph.D.
金额：
--
依托单位：
Institut für Ur- und Frühgeschichte und Vorderasiatische Archäologie
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2015
资助国家：
德国
起止时间：
2014-12-31 至 2019-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/286806412?language=en
关键词：
effect forest vegetation formation mercury

项目摘要

The aim of the proposed project is to study how changes in forest vegetation will affect the accumulation of mercury in lake sediments. This approach builds on the hypothesis that different forest vegetation in lake catchments causes different Hg accumulation rates to forest soils. Moreover, forest type affects production, degradation and release of organic matter (OM) from forest soils, and thus also the transport of mercury to lakes. The proposed project will combine the investigation of long (several millennia) sediment records with known vegetation histories (from pollen analyses) taken from four catchment-lake systems, one with deciduous and three with coniferous vegetation. In addition we will investigate the contemporary relation between OM quality and quantity and Hg sedimentation in the study lakes through POM and DOM analyses. As chemical characteristics of organic matter in soils and assumingly also in sediments are strongly influenced by forest vegetation, we will use a qualitative approach where the OM quality (as defined by Fourier-transform infrared spectroscopy and Pyrolysis-GC-MS) will be related to changes in forest vegetation as derived from the tree pollen distribution in the sediments. Moreover, we will use multivariate statistical approaches to disentangle to which extent the influence of changes in forest vegetation on Hg accumulation in the lake sediments can be distinguished from other processes affecting the Hg load. A deeper understanding of this relationship is seen as the basis to predict the release auf Hg from the widely contaminated surface soils in the Northern Hemisphere to aquatic systems under changing land use or climatic conditions.

该项目的目的是研究森林植被的变化将如何影响湖泊沉积物中汞的积累。该方法基于这样的假设：湖泊流域的不同森林植被导致森林土壤的汞积累率不同。此外，森林类型影响森林土壤中有机物（OM）的产生、降解和释放，从而影响汞向湖泊的迁移。拟议的项目将把对长期（几千年）沉积物记录的调查与取自四个集水湖系统的已知植被历史（来自花粉分析）结合起来，其中一个是落叶植被，三个是针叶植被。此外，我们将通过 POM 和 DOM 分析来研究研究湖泊中 OM 质量和数量与汞沉积之间的当代关系。由于土壤中以及沉积物中有机物的化学特性受到森林植被的强烈影响，我们将使用定性方法，其中 OM 质量（由傅里叶变换红外光谱和热解-GC-MS 定义）将与森林植被的变化源于沉积物中树木花粉的分布。此外，我们将使用多元统计方法来阐明森林植被变化对湖泊沉积物中汞积累的影响在多大程度上可以与影响汞负荷的其他过程区分开来。对这种关系的更深入了解被视为预测在土地利用或气候条件变化下从北半球广泛污染的表层土壤到水生系统的汞释放量的基础。