Heathland Restoration on Former Agricultural Land: Effects of Artificial Acidification on the Availability and Uptake of Toxic Metal Cations I. Green & J. Stockdale & M. Tibbett & A. Diaz Received: 12 January 2006 / Accepted: 4 June 2006 / Published online: 27 July 2006 # Springer Science + Business Media B.V. 2006 Abstract Lowland heath is an internationally impor- tant habitat type that has greatly declined in abun- dance throughout Western Europe. In recent years this has led to a growing interest in the restoration of heathland on agricultural land. This generally requires the use of chemical treatments to return soil chemical conditions to those appropriate for the support of heathland ecosystems. However, the potential for negative impacts on the environment due to the potential of these treatments to increase the availabil- ity of trace metals via raised soil acidity requires investigation. A large-scale field study investigated the effect of two chemical treatments used in heathland restoration, elemental sulphur and ferrous sulphate, on soil acidity and whether it is possible to predict the effect of the treatments on availability of two potentially toxic cations (Al and Cd) in the soil along with their subsequent accumulation in the shoots of the grass Agrostis capillaris. Results showed that both treatments decreased soil pH, but that only elemental sulphur produced a pH similar to heathland soil. The availability of Al, measured by extraction with 1 M ammonium nitrate, could not be predicted by soil pH, depth in the soil and total Al concentration in the soil. By contrast, availability of Cd could be predicted from these three variables. Concentrations of both Al and Cd in the shoots of A. capillaris showed no significant relationship with the extractable concentration in the soil. Results are discussed in light of the possible environmental impacts of the chemical restoration techniques. Keywords aluminium . cadmium . heathland restoration . elemental sulphur . ferrous sulphate . environmental impact 1 Introduction Lowland heath is an internationally important habitat type that has greatly declined in abundance through- out Western Europe (Moore, 1962; Webb, 1990). The principal reasons for the loss of heathland have been its conversion to agricultural land, urban development and, to a lesser extent, the building of golf courses (Moore, 1962; Webb, 1986, 1990; Farrell, 1993). In recent years there has been a growing interest in the restoration of heathland on agricultural land as changes in the Common Agricultural Policy have led to an increase in extensive farming and agri- Water Air Soil Pollut (2007) 178:287–295 DOI 10.1007/s11270-006-9197-8 I. Green (*) : J. Stockdale : A. Diaz The Centre for Ecology and Conservation Biology, The School of Conservation Sciences, Bournemouth University, Talbot Campus, Poole, Dorset BH12 5BB, UK e-mail: igreen@bmth.ac.uk M. Tibbett Centre for Land Rehabilitation, School of Earth and Geographical Sciences, Faculty of Natural and Agricultural Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia