Lift up of Lowlands : beneficial use of dredged sediments to reverse land subsidence
Figueiredo Oliveira, Bruna Raquel - \ 2017
Wageningen University. Promotor(en): Huub Rijnaarts, co-promotor(en): Tim Grotenhuis. - Wageningen : Wageningen University - ISBN 9789462578838 - 229
dredgings - dredging - sedimentation - soil - sediment - subsidence - recycling - environmental engineering - bagger - baggeren - sedimentatie - bodem - sediment - bodemdaling - recycling - milieutechniek
In this thesis, the beneficial use of dredged sediments to reverse land subsidence in lowlands and delta areas is explored. The major constraints for beneficial use of sediments are the contaminant concentrations, and the proper managing of supply and demand of sediments (Chapter 1).
When sediments are transferred from waterways to upland conditions, a series of processes take place that transform the waterlogged sediments into aerated soils, a process known as ripening. To understand the relation between the sediments and the soils formed, physical/chemical and biological processes were studied at three scales: laboratory scale, mesoscale, and field scale. The knowledge obtained with these experiments can provide guidelines to effectively use dredged sediments to reverse land subsidence.
In the laboratory experiments, the environmental conditions were controlled, leading to constant water content and optimal oxygen concentration for biological processes. In the mesoscale experiment, the environmental parameters such as wind, precipitation and temperature, were not controlled as the 1 m3 containers used for these experiments were placed outside, in open air conditions. Still, the water level could be monitored and controlled, and the subsidence of the dredged sediment could be monitored. In the field experiment, the environmental and filling conditions could not be controlled but the changes occurring in the deposit were monitored.
In the first laboratory experiment (Chapter 2) the behaviour of dredged sediments with varying particle size distribution and organic matter content was studied. The dredged sediments were dewatered using suction chambers and then submitted to biochemical ripening during 141 days. The five types of dredged sediments had similar overall behaviour. The most significant observation was that most volume lost during dewatering and biochemical ripening was due to shrinkage and not to organic matter mineralization. Furthermore, the type of organic matter changed in the direction of humification, i.e., more stable compounds were formed. The soils formed from biochemical ripening of dredged sediments had very stable aggregates and the load-bearing capacity was enough to sustain cattle and tractors.
The second laboratory experiment (Chapter 3) was designed to investigate the influence of mixing compost and the solid fraction of swine manure (low in nutrients) with dredged sediments on dewatering and biochemical ripening. When the supply of dredged sediments is too low to compensate for land subsidence, bio-wastes, such as compost and manure, can be mixed with the sediments to reverse land subsidence. The results of this experiment confirm that most volume lost during ripening was due to shrinkage and not due to organic matter mineralization. Adding compost or the solid fraction of manure to the dredged sediments enhances the changes in the type of organic matter and CO2 production, i.e., the addition results in increased rates of organic matter mineralization which is described in the literature as the priming effect. In addition, the undrained shear strength of the mixtures of sediments with compost or manure was three times higher than the measured values for the sediments alone, meaning that organic amendments will improve the characteristics of the soil formed from ripening of sediments.
The mesoscale experiment (Chapter 4) was performed during 400 days in 1m3 containers which allowed to control the water level. Two scenarios were tested: upland deposits in which the sediments are allowed to dry; and underwater deposits in which the water level is always 2 cm above the sediments. It was expected that the upland deposit conditions would lead to a higher subsidence than the underwater conditions. However, subsidence of the sediments was very similar for the two scenarios. Also in these experiments it was observed that most subsidence could be attributed to shrinkage and not organic matter mineralization, and the type of organic matter changed in the direction of humification. Furthermore, the water balance indicated that evapotranspiration results in higher loss of water than drainage. Still, in this case the undrained shear strength after 400 days of experiment was not enough to sustain cattle or tractors even though it increased with time.
The monitored field scale upland deposit of dredged sediments (Chapter 5) is located in the Wormer- en Jisperveld area – North Holland, the Netherlands. The deposit was filled in two stages reaching a maximum height of sediments of 195 cm. After 17 months of monitoring, the subsidence of the sediments was 119 cm to which an extra subsidence of 19.5 cm of the underlying soil due to the overburden pressure was added. The results observed in the upland deposit are in line with the laboratory and mesoscale results since subsidence could also be attributed to shrinkage and no significant changes in the organic matter content were observed. However, in the case of the upland deposit, the type of organic matter changed in the direction of humification during the first 8 months (March to November), then stabilized during 7 months (November to June), and changed in the direction of mineralization afterwards.
The outcomes of this research indicate that dredged sediments have the potential to reverse land subsidence. This statement is supported by the consistent results showing that the decrease in volume of dredged sediments is caused by shrinkage and not to organic matter mineralization as traditionally reported (Chapters 2, 3, 4, and 5).
In addition, in places where composted and stable bio-wastes are available, these can be added to dredged sediments to further reverse land subsidence. Still, in this case special attention should be given to the potential priming effect (Chapter 3).
Finally it is recommended to adapt the current practices of disposal of dredged sediments in upland deposits, since 19.5 cm of subsidence observed for the underlying soil in the upland deposit (Chapter 5), was caused by the overburden pressure of the dredged sediment. From the point of view of avoiding/reversing land subsidence it is recommended to spread thin layers (in the order of cm) of sediments over the land, although this might lead to an increase in the time and costs for the stakeholders involved in dredging and in managing the water boards.
Adapting to an Uncertain Climate: Lessons From Practice
Capela Lourenco, T. ; Rovisco, A. ; Groot, A.M.E. ; Nilsson, C. ; Füssel, H.M. ; Bree, L. van - \ 2014
Switzerland : Springer International Publishing - ISBN 9783319048765 - 182
klimaatadaptatie - milieuwetenschappen - milieutechniek - aardsysteemkunde - klimaatverandering - milieu - klimaat - climate adaptation - environmental sciences - environmental engineering - earth system science - climatic change - environment - climate
Climate change highlights the challenges for long-term policy making in the face of persistent and irreducible levels of uncertainties. It calls for the development of flexible approaches, innovative governance and other elements that contribute to effective and adaptive decision-making. Exploring these new approaches is also a challenge for those involved in climate research and development of adaptation policy. Targeted specifically at policy developers and advisors, practitioners, climate knowledge brokers, researchers and interested adaptation decision-makers, this book differs from other titles addressing climate change adaptation and uncertainty by using real life cases to address distinct and pertinent uncertainties in actual adaptation situations. The authors introduce the role of uncertainties in informing adaptation decisions, showing why and how this is important, and why decisions do not have to wait until uncertainties are resolved. They explore uncertainty assessments supporting decision-making on climate change adaptation, with sections on variability, uncertainty typology, climate change, and projection of risks. A discussion of national adaptation planning follows with sections on sources and levels of uncertainty, communication of uncertainty, and guidance for adaptation planning under uncertainty. The book provides a dozen real-life examples of adaptation decision making in the form of case studies: · Water supply management in Portugal, England and Wales and Hungary · Flooding, including flood risk in Ireland, coastal flooding and erosion in Southwest France, and flood management in Australia’s Hutt River region · Transport and utilities, including the Austrian Federal railway system, public transit in Dresden, and Québec hydro-electric power · Report examining communication of large numbers of climate scenarios in Dutch climate adaptation workshops The concluding section outlines a new support framework for adaptation decisions under uncertainty, as well as guidance, recommendations and decision support for readers to apply in their own work. In the spirit of the newly adopted EU Strategy on Adaptation to Climate Change, the book aims - as does the CIRCLE-2 project from which it emanates - to assist informed decision-making and to provide added value through increased knowledge sharing.
Onderzoek naar schuimproblemen in slibvergisters
Grolle, K.C.F. ; Wierenga, P.A. ; Zeeman, G. - \ 2011
H2O : tijdschrift voor watervoorziening en afvalwaterbehandeling 44 (2011)5. - ISSN 0166-8439 - p. 53 - 54.
afvalwaterbehandeling - milieutechniek - slibzuivering - co-vergisting - schuimen - waste water treatment - environmental engineering - sludge treatment - co-fermentation - foaming
Milieutechnisch onderzoek naar schuimproblemen heeft vaak als doel de schuimbepalende parameter te vinden om de ingrediënten te identifi ceren die de schuimproblemen veroorzaken. In de levensmiddelensector is uitgebreid fundamenteel onderzoek gedaan naar schuim en daar is die schuimbepalende parameter (nog) niet gevonden. In dit artikel worden suggesties gedaan voor milieutechisch onderzoek naar schuimproblemen in slibvergisters op basis van de kennis die opgedaan is in de levensmiddelentechnologie.
MEBOT voor boomkwekerij en fruitteelt, Thema: Doorontwikkelen duurzame gewasbescherming BO-12.03-003.01-001.05
Dijk, W. van; Roelofs, P.F.M.M. ; Sluis, B.J. van der - \ 2011
boomkwekerijen - fruitteelt - gewasbescherming - duurzaamheid (sustainability) - geïntegreerde bestrijding - bedrijfsapplicaties - bedrijfseconomie - milieutechniek - forest nurseries - fruit growing - plant protection - sustainability - integrated control - business software - business economics - environmental engineering
Informatieposter over MEBOT (Milieutechnisch en Economisch Bedrijfsmodel Open Teelten) voor boomkwekerij en fruitteelt
Schoon spoelwater met lamellenseparator : i.s.m. Van Antwerpen Milieutechniek
Dam, M.F.N. van; Duyvestein, R. ; Antwerpen, E. - \ 2010
milieutechniek - waterzuivering - zelfbeheer - systemen - watersystemen - bollen - environmental engineering - water treatment - self management - systems - water systems - bulbs
Informatieposter over schoon spoelwater met behulp van een lamellenseparator, milieutechniek. Met de lamellenseparator wordt het aantal micro-organismen in het spoelwater sterk gereduceerd
Nieuwe (emissievrije) TeeltSystemen (NTS)
Beerling, E.A.M. ; Blok, C. ; Driever, S.M. ; Ruijs, M.N.A. ; Vermeulen, T. ; Weel, P.A. van; Wurff, A.W.G. van der - \ 2010
emissie - beperking - kastechniek - milieutechniek - glastuinbouw - kassen - teeltsystemen - emission - restraint - greenhouse technology - environmental engineering - greenhouse horticulture - greenhouses - cropping systems
Informatieposter over Nieuwe (emissievrije) TeeltSystemen (NTS) naar aanleiding van het Europees beleid Kaderrichtlijn Water (KRW) en afspraak Glami: nagenoeg geen emissies uit glastuinbouw in 2027
Groen bouwen met hernieuwbare grondstoffen
Kasper, G.J. - \ 2009
bouwmaterialen - vervangbare hulpbronnen - toepassingen - industriële toepassingen - milieu - milieutechniek - biobased economy - building materials - renewable resources - applications - industrial applications - environment - environmental engineering - biobased economy
Deze info sheet geeft informatie over hernieuwbare grondstoffen toegepast in bouwmaterialen. Besproken wordt welke hernieuwbare grondstoffen geschikt zijn, waar ze toegepast kunnen worden en welke milieuvoordelen ze hebben.