www.VadoseZoneJournal.org Willingness to Pay for Soil Informaton Derived by Digital Maps: A Choice Experiment Approach Soil surveys and the informaton they provide are commonly believed to be good invest- ment, with signifcant benefts accrued to their users. To date, the empirical evidence for this comes from studies that have shown how enhanced soil informaton can alter agricul - tural practces to yield higher returns. This study atempts to estmate the economic value of soil informaton generated by a host of new proximal and in situ geophysical methods for the assessment of the following soil proper tes: carbon content, water content, clay content, bulk density, and soil depth. The study also adopts a novel approach to the eco- nomic valuaton of soil informaton by employing for the frst tme a choice experiment to estmate the willingness-to-pay (WTP) of potental users of the digital maps and their features. The choice experiment took the form of an online survey, administered to about a thousand individuals from the wider soil community. The results reveal signifcant WTP for maps of high resoluton and accuracy that ofer map interpretaton in additon to a number of soil propertes. Abbreviatons: ASC, alternatve-specifc constant; CE, choice experiment; EMI, electromagnetc inducton; ERT, electrical resistvity tomography; GPR, ground-penetratng radar; IIA, independence of irrelevant alternatves; IID, independently and identcally distributed; MNL, multnomial logit; RPL, Random Parameter Logit; WTP, willingness-to-pay. It is a common claim within the soil community that soil surveys practically pay for themselves, an assertion that is backed up by a number of studies (Bie and Ulph, 1972; Carrick et al., 2010; Giasson et al., 2000). Tese studies have tried to quantify the economic value of soil information indirectly, by linking it with higher agricultural pro- ceeds stemming from improved land management practices that are informed by enhanced information. For instance, Carrick et al. (2010) estimated signi fcant economic returns from a targeted application of a nitrogen leaching technology to N-leaching hotspots iden- tifed by a new soil map. Similarly, Giasson et al. (2000) and Bie and Ulph (1972) present tools for optimizing agricultural land use across soil types in a context of decision-making under uncertainty. Tey both demonstrate how higher payofs can be associated with soil surveys of higher purity. Another way that the economic value of soil information has been demonstrated indirectly is through the development of such tools as Green Credits (Hunink et al., 2009). Tis is a fnancial mechanism that enables upstream farmers to practice water and management activities that beneft these farmers and downstream water users. As this mechanism draws heavily on sound information regarding land use as well as soil properties, it can be argued that the payments made reveal, at least in part, the economic value of the soil maps involved. Te object of economic valuation of this study is not the information derived from tradi- tional soil surveys but from a host of new sensing technologies for non-invasive character- ization of the soil geophysical properties. Tese sensing technologies have been developed by DIGISOIL project (Grandjean et al., 2010), the main goal of which has been to develop an advanced soil mapping tool, by testing, assessing, and integrating a range of new sens- ing tools capable of producing digital soil maps of high accuracy and fne resolution. Te specifc objectives focused on (i) adapting, testing, and validating the geophysical tech- nologies; (ii) establishing correlations between measured geophysical parameters and soil properties involved in soil functions and soil threats such as erosion, compaction, organic matter decline; and (iii) evaluating the technical feasibility and cost-efectiveness of the mapping tool. Te identifed sensing systems included the ground-penetrating radar (GPR), This study employs a novel approach to the estimation of the economic value of digital soil maps, generated by a host of new proximal geophysi- cal processes and technologies. Using a Choice Experiment, the study dem- onstrates that there is significant willingness-to-pay for the soil maps and their features. I. Diafas, Baarsjesweg 271/3, Amsterdam, Netherlands; L. Montanarella and P. Panagos, European Commission, Joint Research Centre, Insttute for Environment and Sustainability, Via E. Fermi 2749, I-21027 Ispra (VA), Italy. *Corresponding author (diafasj@gmail.com). Vadose Zone J. doi:10.2136/vzj2012.0198 Received 17 Dec. 2012. Special Section: Digital Soil Mapping Iason Diafas* Panos Panagos Luca Montanarella © Soil Science Society of America 5585 Guilford Rd., Madison, WI 53711 USA. All rights reserved. No part of this periodical may be reproduced or transmited in any form or by any means, electronic or mechanical, including pho- tocopying, recording, or any informaton storage and retrieval system, without permission in writng from the publisher. Published October 4, 2013