Contents
1 Abstract ..........................................................................................................
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2 Introduction ....................................................................................................
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2.1 Early diagenesis ...............................................................................
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2.2 Behaviour of heavy metals and nutrients during early diagenesis...
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2.3 Methods used in the study of early diagenesis .................................
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3 Methods and materials ....................................................................................
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3.1 Location of the study area ................................................................
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3.1.1 Neckar River and its tributaries .........................................
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3.1.2 Major rivers and Lake Constance in Germany ..................
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3.1.3 Lean River (China), Moscow Rwer and Oka River
(Russia) ...............................................................................
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3.2 Sampling ..........................................................................................
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3.3 Analysis ............................................................................................
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3.3.1 Solid phases ......................................................................
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3.3.2 Porewater ...........................................................................
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4 Results and discussion ....................................................................................
4. l Early diagenesis in the sediments of the Neckar River and its
tributaries ..........................................................................................
4.1. I Decomposition of organic matter by different oxidants ....
4.1.2
4.1.3
4.1.4
4.1.5
4.1.6
4.1.7
4.1.8
4.1.9
Denitrification in the sediments .........................................
Cycling of manganese in the sediments .............................
Cycling of iron in the sediments ........................................
Sulfate reduction ................................................................
Ammonium production ......................................................
Alkalinity, Ca, Mg, and conductivity in the porewater ......
Phosphorus in the sediments and porewater ......................
Effect of oxygen-depleting substances (NH~', Fe 2~) .....
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