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Informations
Publié par | universitat_bremen |
Publié le | 01 janvier 2010 |
Nombre de lectures | 29 |
Langue | Deutsch |
Poids de l'ouvrage | 9 Mo |
Extrait
ACID SULFATE SOILS
PROCESSES AND ASSESSMENT
Dissertation
zur Erlangung des Doktorgrades der Naturwissenschaften (Dr. rer. nat.)
am Fachbereich Geowissenschaften
der Universität Bremen
vorgelegt von
Jens Gröger
Bremen, November 2010
Gutachter:
Prof. Dr. Horst D. Schulz
Prof. Dr. Tobias Mörz
Promotionskolloquium: 28. Januar 2011
Contents
V
Contents
Summary ....................................................................................................................IX
Zusammenfassung................................................................................................... XII
1| Introduction.............................................................................................................1
1.1 Occurrence and genesis of acid sulfate soils............................................................................1
1.2 Acid sulfate soils and their impacts in the North German lowlands ...................................4
1.3 Processes in acid sulfate soils.....................................................................................................6
1.3.1 Formation of iron sulfides ....................................................................................................6
1.3.2 Sulfide Oxidation ...................................................................................................................8
1.3.2.1 Oxidation of pyrite by direct reaction with dissolved oxygen............................9
1.3.2.2 Pyrite oxidation by ferric iron...............................................................................10
1.3.2.3 Oxidation of iron monosulfides............................................................................12
1.3.3 Sulfur bearing oxidation products.....................................................................................13
1.3.3.1 Jarosite......................................................................................................................13
1.3.3.2 Schwertmannite ......................................................................................................14
1.4 Evolution of acid sulfate soils ..................................................................................................15
1.4.1 Soil profile evolution ...........................................................................................................15
1.4.2 Export of acidity...................................................................................................................16
2| Scope and objectives .............................................................................................18
3| Quantitative Recovery of Elemental Sulfur and Improved Selectivity in a
Chromium- Reducible Sulfur Distillation .........................................................21
4| Das Angriffspotential sulfatsaurer Böden in Norddeutschland – Der
kombinierte Säure- und Sulfatangriff auf Beton...............................................23
5| Cycling of trace metals and rare earth elements (REE) in acid sulfate soils in
the Plain of Reeds, Vietnam.................................................................................25
5.1 Introduction...............................................................................................................................27
5.2 Materials and methods .............................................................................................................28
5.2.1 Geology and hydrology of the study area .........................................................................28
5.2.2 Field work..............................................................................................................................29
5.2.3 Chemical analyses ................................................................................................................30
5.2.4 Chemical equilibrium modeling ........................................................................................30
5.2.5 Core characteristics..............................................................................................................30
5.2.5.1 Core THD32
5.2.5.2 Core TLD .................................................................................................................32
5.2.5.3 Core THT32
5.3 Results and Discussion .............................................................................................................33
5.3.1 Oxidation, acidification and leaching ...............................................................................33
5.3.2 Formation of authigenic enrichments and their controls ..............................................35
5.3.2.1 Enrichments of trace metals (at elevated pH levels) ..........................................35
5.3.2.2 Trace metal enrichments under acidic conditions in the vicinity of the
redoxcline.................................................................................................................37
5.3.2.2.1 Evidence for trace metal sulfide precipitation...........................................38
5.3.2.2.2 Modeling of a sequential precipitation.......................................................40
5.3.2.3 Authigenic enrichments of Pb and As in the oxidized soil column ................43
5.3.2.4 Reductive dissolution processes............................................................................45
5.3.3 Authigenic enrichments of REEs.......................................................................................47
5.3.3.1 Authigenic enrichments of REEs at elevated pH................................................47 Contents
VI
5.3.3.2 Authigenic enrichments of REEs under acidic conditions .............................. 49
5.4 Conclusions............................................................................................................................... 50
5.5 Acknowledgements .................................................................................................................. 51
5.6 References... 51
6| A guideline for the assessment of potential acid sulfate soils (PASS) affected
by construction works in Northern Germany..................................................57
6.1 Introduction .............................................................................................................................. 58
6.2 Assessment approach............................................................................................................... 59
6.3 Analytical methods and assessment....................................................................................... 59
6.4 Current status and outlook ..................................................................................................... 60
6.5 Acknowledgements 61
6.6 References.................................................................................................................................. 61
7| Handlungsempfehlung zur Bewertung des Versauerungspotentials von
Aushubmaterial durch reduzierte anorganische Schwefelverbindungen ......63
7.1 Abkürzungsverzeichnis ........................................................................................................... 67
7.2 Darstellung der Problematik „Sulfatsaure Böden“ .............................................................. 68
7.3 Anwendungsbereich und Zweck............................................................................................ 69
7.3.1 Anwendbarkeit .................................................................................................................... 69
7.3.2 Allgemeine Hinweise .......................................................................................................... 70
7.3.3 Art der Böden ...................................................................................................................... 70
7.3.3.1 Auftreten ................................................................................................................. 70
7.3.3.2 Typische Erscheinungsformen............................................................................. 70
7.4 Vorerkundung / Kartenauswertung ...................................................................................... 71
7.5 Probenahme und Probenbehandlung /-lagerung ................................................................ 71
7.5.1 Obligatorische Messungen/Beschreibungen ................................................................... 71
7.5.2 Optionale Messun