This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process which may lead to differences between this version and the Version of Record. Please cite this article as doi: 10.1002/esp.4360 This article is protected by copyright. All rights reserved. Gully and soil and water conservation structure densities in semi-arid northern Ethiopia over the last 80 years Etefa Guyassa 1,2 *, Amaury Frankl 1,3 , Amanuel Zenebe 2 , Jean Poesen 4 , Jan Nyssen 1 1 Department of Geography, Ghent University, Belgium. 2 Department of Land Resources Management and Environmental Protection, Mekelle University, Ethiopia. 3 Research Foundation Flanders (FWO), Brussels, Belgium. 4 Division of Geography, Department of Earth and Environmental Sciences, KU Leuven, Belgium. *corresponding author; email: etefag@gmail.com, mobile: +251914783635