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Schwefelisotopenfraktionierung in abwasserbelasteten Sedimenten - biogeochemische Umsetzungen und deren Auswirkung auf den Schwermetallhaushalt

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Book Series: Karlsruher Mineralogische und Geochemische Hefte ISSN: 16182677 ISBN: 3937300503 Year: Volume: 25 Pages: XVIII, 218 p. DOI: 10.5445/KSP/1000002977 Language: GERMAN
Publisher: KIT Scientific Publishing
Subject: Astronomy (General)
Added to DOAB on : 2019-07-30 20:02:00

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Aus undichten Abwasserkanälen versickerndes Abwasser unterliegt einer Reihe chemischer und biologischer Umsetzungen bzw. Wechselwirkungen während der Passage durch den ungesättigten Untergrund. Diese Prozesse bestimmen das Schicksal im Abwasser enthaltener, potentiell gefährlicher Substanzen.Die im Rahmen dieser Arbeit durchgeführten Untersuchungen haben zum Ziel, mikrobielle und geochemische Umsetzungsprozesse unterhalb defekter Abwasserkanäle zu charakterisieren und ihre Auswirkungen auf den Schwermetallhaushalt zu erfassen. Der Schwerpunkt liegt hierbei auf der Schwefelisotopenzusammensetzung des versickernden Abwassers und der abwasserbelasteten Sedimente. Veränderungen in der Schwefelisotopenzusammensetzung sollen auf ihre Eignung als Indikator für das Redoxmilieu in den abwasserbelasteten Sedimenten überprüft bzw. zu dessen Charakterisierung und damit auch zu derjenigen möglicher Umsetzungsprozesse herangezogen werden.In Laborversuchen mit Bakterienkulturen konnte ein abwasserspezifischer Einfluss auf das Ausmaß der Isotopenfraktionierung bei der bakteriellen Sulfatreduktion nicht nachgewiesen werden, so dass davon auszugehen war, dass sich die Fraktionierung in abwasserbelasteten Sedimenten nicht wesentlich von der in anderen anaeroben Milieus unterscheidet.Die Versuche zeigten jedoch Zusammenhänge auf, die von eher grundlegender Bedeutung sind, auch außerhalb des Bereichs abwasserbelasteter Sedimente. Es konnte gezeigt werden, dass die Zugabe des Hemmstoffs Molybdat in hohen Konzentrationen zur Verringerung des Fraktionierungsfaktors führt. Experimente, die bei verschiedenen Inkubationstemperaturen durchgeführt wurden, verdeutlichten, dass der inverse Zusammenhang zwischen spezifischer Sulfatreduktionsrate und Fraktionierungsfaktor unter gestressten Wachstumsbedingungen nicht uneingeschränkt gilt. Daneben konnte ein Einfluss des Zellwachstums auf die Entwicklung des Fraktionierungsfaktors festgestellt werden.In Säulenversuchen wurden die Veränderungen des Abwassers bei der Untergrundpassage sowie seine Auswirkungen auf den Untergrund und das Grundwasser verfolgt bzw. ermittelt. Durch variierende Betriebsweisen und die Verwendung unterschiedlicher Abwasserarten wurden verschiedene Leckagearten simuliert. Dabei zeigten sich jeweils in Abhängigkeit von der Betriebsweise der Säulen verschiedene Entwicklungswege und Stabilitätszustände in Bezug auf die biogeochemischen Umsetzungsprozesse und die Redoxverhältnisse.Langzeitbeobachtungen der Veränderungen des Sulfatgehalts und des d34S-Werts im Ablaufwasser der Säulen ermöglichten es hiernach, die Stabilität der Redoxbedingungen im ungesättigten Untergrund abzuschätzen. Die Untersuchung der Säulensande nach der Abwasserversickerung zeigte, dass die verschiedenen Betriebsweisen der Säulen zur Ausbildung charakteristischer Tiefenprofile des d34S-Werts des Gesamtschwefels bzw. des d34S-Werts einzelner Schwefelfraktionen führten, welche Lage bzw. Verteilung unterschiedlicher Redoxbereiche nachzeichneten. Bezüglich der Auswirkungen auf den Schwermetallhaushalt konnte ein Einfluss des Abwassers bzw. der durch dieses bewirkten Prozesse über das gesamte Tiefenprofil (1,20 m) beobachtet werden. Eine Anreicherung von Schwermetallen wurde v.a. in einer Kolmationsschicht am Säulenbeginn sowie im Bereich von ca. 40 cm unterhalb der Abwasseraufgabestelle festgestellt. Die durch die Abwasserversickerung bewirkte Absenkung des Redoxpotentials im Untergrund führte jedoch auch zu einer Mobilisierung im Ausgangsfüllmaterial vorhandener Schadstoffe, und zwar über das gesamte Profil hinweg.

Metallmatrixverbunde mit Verstärkungselementen aus metallischem Glas Ni??Nb??Ta?? – Herstellung und Charakterisierung

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Book Series: Schriftenreihe des Instituts für Angewandte Materialien, Karlsruher Institut für Technologie ISSN: 21929963 ISBN: 9783731507826 Year: Volume: 75 Pages: XVI, 402 p. DOI: 10.5445/KSP/1000081432 Language: GERMAN
Publisher: KIT Scientific Publishing
Subject: Technology (General)
Added to DOAB on : 2019-07-28 18:37:01
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AlSi12-based metal matrix composites using metallic glass Ni??Nb??Ta?? as reinforcement were produced via gas pressure melt infiltration technique. Comprehensive investigations were performed to determine the composite´s microstructural, mechanical and thermal properties as well as damage mechanisms. The results contribute to a better understanding on the material´s processing-structure-property relations.

Sustainable Drainage Systems

ISBN: 9783038420927 9783038420910 Year: Pages: XII, 236 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Added to DOAB on : 2016-07-12 11:05:05
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Soil Water Conservation. Dynamics and Impact

Authors: --- --- ---
ISBN: 9783038978527 9783038978534 Year: Pages: 258 DOI: 10.3390/books978-3-03897-853-4 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- Environmental Technology
Added to DOAB on : 2019-04-25 16:37:17
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Human needs like food and clean water are directly related to good maintenance of healthy and productive soils. A good understanding of human impact on the natural environment is therefore necessary to preserve and manage soil and water resources. This knowledge is particularly important in semi-arid and arid regions, where the increasing demands on limited water supplies require urgent efforts to improve water quality and water use efficiency. It is important to keep in mind that both soil and water are limited resources. Thus, wise use of these natural resources is a fundamental prerequisite for the sustainability of human societies. This book collects 15 original scientific contributions addressing the state of the art of soil and water conservation research. Contributions cover a wide range of topics, including (1) recovery of soil hydraulic properties; (2) erosion risk; (3) novel modeling, monitoring and experimental approaches for soil hydraulic characterization; (4) improvement of crop yields; (5) water availability; and (6) soil salinity. This collection provides more insights into conservation strategies for effective and sustainable soil and water management.

Keywords

soil moisture storage --- van Genuchten model --- distributed model --- Xin’anjiang model --- TOPMODEL --- bimsoils --- critical hydraulic gradient (CHG) --- response surface methodology --- multi-parameter evaluation --- laboratory experiment --- soil block --- subsurface flow --- macropore network --- spatial scale --- polyurethane foam --- hillslope --- soil water content --- field observation --- three-dimensional model --- numerical model --- delta plain --- shallow groundwater --- unsaturated soil --- Richards equation --- the Trefftz method --- transient --- the meshless method --- vineyards --- infiltration rate --- age of planting --- saturated hydraulic conductivity --- Malawi --- conservation agriculture --- peer effects --- decision tree modeling --- olive grove --- sap flow --- relative transpiration --- FDR sensor --- EM38 --- fraction transpiration soil water --- transdisciplinary research --- Follow-the-Innovation --- innovation development --- electromagnetic induction meter (EM) --- The Agricultural Production Systems sIMulator (APSIM) software --- AquaCrop --- cereals --- DSSAT --- field scattering --- food security --- microdose fertilization --- rainfall variability --- tied ridges --- upgrading strategies --- soil properties --- saturated soil hydraulic conductivity --- soil infiltration --- Beerkan method --- post-fire soil hydraulic characterization --- infiltration --- bottomless bucket method --- single-ring infiltrometer --- field-saturated soil hydraulic conductivity --- data analysis procedures --- environmental change --- local perception --- food security --- adaptation --- soil tillage --- tillage erosion --- seedbed preparation --- water infiltration --- nitrogen use efficiency --- specific leaf water content --- vegetable production --- soil --- yield --- water and soil conservation --- sustainable land management --- soil erosion --- soil water storage --- water infiltration --- water availability --- crop yields

Advances in Groundwater Flow and Solute Transport: Pushing the Hidden Boundary

Authors: --- ---
ISBN: 9783039210749 / 9783039210756 Year: Pages: 196 DOI: 10.3390/books978-3-03921-075-6 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- Environmental Technology
Added to DOAB on : 2019-12-09 11:49:15
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In recent decades, the study of groundwater flow and solute transport has advanced into new territories that are beyond conventional theories, such as Darcy’s law and Fick’s law. The studied media have changed from permeable porous and fractured ones to much less permeable ones, such as clay and shale. The studied pore sizes have also changed from millimetres to micro-meters or even nano-meters. The objective of this Special Issue is to report recent advances in groundwater flow and solute transport that push the knowledge boundary into new territories which include, but are not limited to, flow and transport in sloping aquifer/hillslopes, coupled unsaturated and saturated flow, coupled aquifer-vertical/horizontal/slant well flow, interaction of aquifer with connected and disconnected rivers, non-Darcian flow, anomalous transport beyond the Fickian scheme, and flow and transport in extremely small pore spaces such as shale and tight sandstones. Contributions focusing on innovative experimental, numerical, and analytical methods for understanding unconventional problems, such as the above-listed ones, are encouraged, and contributions addressing flow and transport at interfaces of different media and crossing multiple temporal and spatial scales are of great value

Protein Crystallization under the Presence of an Electric Field

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ISBN: 9783038975199 / 9783038975205 Year: Pages: 90 DOI: 10.3390/books978-3-03897-520-5 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- General and Civil Engineering --- Electrical and Nuclear Engineering
Added to DOAB on : 2019-08-28 11:21:27
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This book entitled “Protein Crystallization under the Presence of an Electric Field” covers recent trends and original contributions on the use of electric fields (internal and external) for applications for nucleation control and the effect on the kinetics of crystallization processes. This book also includes basic strategies for growing crystals of biological macromolecules for characterization via X-ray and neutron diffraction as well as using modern X-ray-free electron-lasers. There are six main topics covered on this book, including recent insights into the crystallization process from nucleation and growth peculiarities, when using different kinds of electric fields; the effect of external electric fields on the kinetics of the dislocation-free growth of model proteins; the use of very strong external electric fields for the crystallization of a model protein glucose isomerase; and the use of alternant electric fields using different kinds of pulses and their combination with strong magnetic fields. There are also contributions related to applications in developing electron-transfer devices as well as graphene-based platforms for electrocrystallization and in situ X-ray diffraction characterization.

Agricultural Irrigation

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ISBN: 9783039219223 / 9783039219230 Year: Pages: 172 DOI: 10.3390/books978-3-03921-923-0 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Biology --- Agriculture (General)
Added to DOAB on : 2019-12-09 11:49:16
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Agriculture is certainly the most important food supplier while it globally accounts for more than 70% of water used and contributes significantly to water pollution. Irrigated agriculture is facing rising competition worldwide for access to reliable, low cost, and high-quality water resources. However, irrigation as the major tool and determinant of affecting agricultural productivity and environmental resources plays a critical role in food security and environment sustainability. Innovative irrigation technologies and practices may enhance agricultural water efficiency and production, in the meantime decrease the water demand and quality issues. I am very pleased to invite you to submit manuscripts in agricultural irrigation which assess current challenges and offer improvement approaches and opportunities for future irrigation.

Assessment and Governance of Sustainable Soil Management

Authors: --- --- ---
ISBN: 9783039214792 / 9783039214808 Year: Pages: 310 DOI: 10.3390/books978-3-03921-480-8 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Biology --- Agriculture (General)
Added to DOAB on : 2020-01-30 16:39:46
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The role of soils for achieving the Sustainable Development Goals is multifarious. Soils are the essential basis for food and biomass provision in support of food security (SDG 2) and energy security (SDG 7). Soil carbon sequestration is paramount for climate action (SDG 13). Soil-mediated water purification and retention, nutrient and matter cycling, and soils habitat functions are essential for maintaining ecosystem services and biodiversity (SDG 15). Healthy soils perform well in all these functions simultaneously. However, the globally increasing demand for food, fiber, and bio-based products poses massive challenges to soil health. Minimizing trade-offs between biomass production and soil health requires systemic approaches to assessment and governance of sustainable soil management in agriculture and food systems. It provides interdisciplinary insights into key questions: What are the impacts of agricultural management practices on sustainability targets in specific geophysical and socio-economic contexts? What are the opportunities and risks of future trends such as climate change, digitalization, and emerging technologies for soil management and soil health? How can institutions and governance instruments be improved to enable decision makers to take action on sustainable soil management? The book was initiated in the frame of the National German research program ‘BonaRes—Soil as a sustainable resource for the bioeconomy’, and it is meant to trigger interdisciplinary thinking.

Keywords

conservation agriculture --- crop–livestock interactions --- Syria --- soil health --- agricultural innovation --- arid oasis --- combination of modern and indigenous knowledge --- Driver-Pressure-State-Impact-Response sustainability framework --- bayesian network --- soil functions --- conservation agriculture --- conventional farming --- zero tillage --- environmental zones --- phosphorus --- legal comparison --- governance --- sustainable agriculture --- fertilization --- soil protection --- Germany --- Costa Rica --- Nicaragua --- crop rotation modelling --- spatially explicit --- dynamic programming --- gross income --- carob --- yield --- soils --- desertification --- coffee by-products --- nutrient composition --- N leaching --- production --- so-called organic fertilizer --- ecosystem services --- governance --- institutions --- land --- property rights --- soils --- sustainability --- landowner --- tenant --- rent price --- rent proportion --- yield potential --- sustainable soil management --- soil degradation --- soil functions --- soil framework directive --- soil policy --- soil threats --- contamination --- sealing --- soil compaction --- risk assessment --- soil functions --- soil management --- subsoil --- compaction --- agricultural yields --- soil functions --- societal acceptance --- farmer motivations --- subsoil loosening --- alfalfa --- sustainable soil management --- resource scarcity --- Germany --- ecosystem services --- soil food web --- earthworms --- monitoring --- water infiltration --- agricultural policy --- behavioural studies --- literature review --- soil functions --- soil pressures --- justifying soil protection --- sustainable soil management --- creation ethics --- Laudato si’ --- property rights --- German Constitutional Law --- soil --- ecosystem services --- land management --- soil remediation --- Europe --- soil functions --- agricultural practices --- sustainability assessment --- ecosystem services --- resource use efficiency --- soil policy --- soil governance

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