DILUTION OF PB-210 BY ORGANIC SEDIMENTATION IN LAKES OF DIFFERENT TROPHIC STATES, AND APPLICATION TO STUDIES OF SEDIMENT-WATER INTERACTIONS
DILUTION OF PB-210 BY ORGANIC SEDIMENTATION IN LAKES OF DIFFERENT TROPHIC STATES, AND APPLICATION TO STUDIES OF SEDIMENT-WATER INTERACTIONS
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DOI：
10.4319/lo.1986.31.3.0584
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发表时间：
1986-05-01
影响因子：
4.5
通讯作者：
BRENNER, M
中科院分区：
文献类型：
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作者：
BINFORD, MW;BRENNER, M
湖泊沉积物反映了水体的状况，可用于快速、综合测量湖沼学变量。从营养状态差异很大的12个佛罗里达[美国]湖泊（用卡尔森营养状态指数表示：TSI）中提取的210 Pb测年岩心的检验表明，有机物的净积累率与水体中的初级生产力有关。在其他26个湖泊的活性无支持的210 Pb g-1有机质在表层沉积物中的营养状态呈负相关，因此，有机积累率。从这一观察，我们开发了一种新的方法，使用沉降210铅作为稀释示踪剂，计算净沉积积累率的任何材料在表层泥。我们证明了生物重要材料（C，N，P和色素）的净损失率与其各自的水浓度（表示为TSI）之间的密切关系。将净沉积物累积率的所有四个变量的多元回归模型解释了高达70%的湖到湖的TSI变化。210 Pb稀释法可用于物质循环、古湖泊学和沉积物堆积过程的研究。
Lake sediments reflect conditions in the water column and can be used for rapid, integrative measurements of limnological variables. Examination of 210Pb-dated cores from 12 Florida [USA] lakes of widely differing trophic state (expressed as Carlson''s trophic state index: TSI) shows that net accumulation rate of organic matter is related to primary productivity in the water column. In 26 other lakes the activity of unsupported 210Pb g-1 organic matter in surficial sediments is inversely related to trophic state and, therefore, to organic accumulation rate. From this observation we develop a new method that uses fallout 210Pb as a dilution tracer to calculate net sedimentary accumulation rates of any material in surface mud. We demonstrate strong relationships between net loss rates of biologically important materials, (C, N, P, and pigments) and their respective water concentrations (expressed as TSI). Multiple regression models incorporating net sediment accumulation rates of all four variables explain up to 70% of the lake-to-lake variation of TSI. The 210Pb-dilution method has applications for studies of material cycling, paleolimnology, and sedimnet accumulation processes.