Co-utilization of Rockdust, Mineral Fines and Compost
Working towards integrated resource recycling and use
Robin A.K. Szmidt & John Ferguson
Abstract
For those who have seen the regeneration of poor soils into highly productive systems through the practice of soil remineralization the empirical evidence has been sufficient to convince many that there is something of great interest happening in soils treated with rock dusts and other mineral sources. The early history of soil remineralization in Scotland was the result of the vision and commitment of Cameron and Moira Thomson of the Sustainable Ecological Earth Regeneration (SEER) Centre just outside Pitlochry in Highland Perthshire. These remarkable people championed the issue to the point where it is gradually gaining main stream interest. This reflects growing interest in the protection of soils as a fundamental resource of any sustainable society, the clear relationship between soils and the wider environment and the relationship between soils, the foods they grow and human health; of fundamental importance as Scotland increasingly focuses on the challenges of sustainable development.
Today, the major attention in policy areas as diverse as climate change, resource management and the many links between human diet and health are focusing attention on new ways of protecting our environment and human welfare. Soil remineralization may have the potential to contribute to reducing carbon in our atmosphere by increasing the potential to lock more carbon into soils and biomass. By co-utilising rock dusts with composted organic wastes to create alternative soil fertility systems we could maximise the value-added market potential for these composts in areas of large scale usage such as agriculture, thus avoiding the environmental and social impacts of landfilling these wastes. Their use could potentially reduce diffuse pollution from agricultural systems, particularly in sensitive areas and they may also create a valuable edge to the growing organics production sector as the connection between the health of our soils and the nutritional value of the foods they produce becomes better understood.
What is clear is that the interactions within soils between plant root systems, the microbial microflora, organic matter and minerals are complex. In order to better evaluate and validate the various claims made on behalf of soil remineralization a focused programme of research is necessary. This report pulls together our current knowledge on soil remineralization from a growing body of work across the globe and sets out a number of areas where research would assist in validating the benefits of soil remineralization and guiding future environmental, agricultural and health policy. We hope it will be of use to practitioners of various disciplines in contributing to a safer and healthier world.
SEPA Waste and Resource Strategy Unit