We lose ground: Global assessment of land subsidence extent
A. Dinar and Y. Li
University of California, Riverside, USA
E. Esteban, E. Calvo
University of Zaragoza and AgriFood Institute of Aragon, Spain
G. Herrera-Garcia, P. Ezquerro
Geological Survey of Spain, Madrid, Spain
P. Teatini
University of Padova, Padova, Italy
R. Tomas
University of Alicante, Alicante, Spain
J. Albiac
Universidad Politécnica de Madrid, Madrid, Spain
Depletion of groundwater aquifers along with all of the associated quality and quantity problems which affect
profitability of direct agricultural and urban users and linked groundwater-ecosystems have been recognized
globally. During recent years, attention has been devoted to land subsidence - the loss of land elevation that occurs
in areas with certain geological characteristics associated with aquifer exploitation. Despite the large socioeconomic
impacts of land subsidencemost of these effects are still not well analyzed and not properly recognized
and quantified globally. In this paper we developed a land subsidence impact extent (LSIE) index that is based on
10 land subsidence attributes, and applied it to 113 sites located around the worldwith reported land subsidence
effects. We used statistical means to map physical, human, and policy variables to the regions affected by land
subsidence and quantified their impact on the index. Our main findings suggest that LSIE increases between
0.1 and 6.5% by changes in natural processes, regulatory policy interventions, and groundwater usage, while
holding all other variables unchanged. Effectiveness of regulatory policy interventions varies depending on the
lithology of the aquifer system, in particular its stiffness. Our findings suggest also that developing countries
are more prone to land subsidence due to lower performance of their existingwater governance and institutions.
