From the grave to the cradle – soil formation from urban waste materials
Dr Thomas Nehls from Technische Universitaet Berlin will give this seminar "From the grave to the cradle – soil formation from urban waste materials" at the James Hutton Institute in Aberdeen. This seminar will also be broadcast live to the Dundee site.
Abstract
Through continuous development and expansion of urban areas, living soils have been sealed and their ability to perform vital ecosystem functions, such as regulating water quality and hosting flora and fauna has been limited or lost completely. This trend is projected to continue as the world’s population becomes increasingly urbanised. The European Commission, for example, now recognises that vast areas of the EU member states continue to the sealed annually, with according loses of productive and fertile land.
Along with a loss of soils, urban waste materials continue to accrue, yet have hardly or only incompletely been re-used locally, instead being preferentially transported to be incinerated, dumped in landfill, or lie bare elsewhere. When natural soils are no longer available, constructing soils from locally available wastes or planting engineered substrates made from combinations of waste materials may at once re-introduce soils to the built environment and dispose of wastes. Previously organic wastes such as food residues, green wastes or sewage sludge have been composted and commonly re-used for soil amendment but other urban waste materials such as concrete, bricks, railway track ballasts, charcoal, ash, paper mill residues or coffee grounds have stockpiled awaiting re-use or removal.
In this seminar, the usability of a variety of urban wastes and their mixtures will be discussed in terms of the construction of new urban soils with special attention to soil physical and chemical properties and their contents and availability of key nutrients, such as phosphorus. Case studies will illustrate the benefits and problems arising from constructing new urban soils from wastes and assess the long term viability of this practice.
Biography
Dr Thomas Nehls is a researcher and lecturer in urban soils, urban resources and urban hydrology at Technische Universitaet Berlin, Germany. His specialization is paved soils, surface water run-off and functional remediation of paved soils by facade greening with the use of waste materials for the construction of planting substrates. He studied in Bayreuth, Germany, receiving a Diploma in 2002 (charcoal in soils) and from the graduate school on urban ecology in Berlin he received his PhD in 2007 on paved urban soils. Since then he has taken on the role of head of laboratory at chair for soil conservation.
Thomas has recently joined the EU COST ‘urban agriculture Europe’ working group 5, on soils, waters and wastes in relation to urban food growing, to highlight the importance of managing natural resources in urban areas to close nutrient loss loops and maintain functionality in urban soils.
This Seminar will be hosted by Dr Luke Beesley.
