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    Analyzing precipitationsheds to understand the vulnerability of rainfall dependent regions
    (München : European Geopyhsical Union, 2012) Keys, P.W.; van der Ent, R.J.; Gordon, L.J.; Hoff, H.; Nikoli, R.; Savenije, H.H.G.
    It is well known that rivers connect upstream and downstream ecosystems within watersheds. Here we describe the concept of precipitationsheds to show how upwind terrestrial evaporation source areas contribute moisture for precipitation to downwind sink regions. We illustrate the importance of upwind land cover in precipitationsheds to sustain precipitation in critically water stressed downwind areas, specifically dryland agricultural areas. We first identify seven regions where rainfed agriculture is particularly vulnerable to reductions in precipitation, and then map their precipitationsheds. We then develop a framework for qualitatively assessing the vulnerability of precipitation for these seven agricultural regions. We illustrate that the sink regions have varying degrees of vulnerability to changes in upwind evaporation rates depending on the extent of the precipitationshed, source region land use intensity and expected land cover changes in the source region.
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    Challenges and opportunities in mapping land use intensity globally
    (Amsterdam : Elsevier, 2013) Kuemmerle, Tobias; Erb, Karlheinz; Meyfroidt, Patrick; Müller, Daniel; Verburg, Peter H.; Estel, Stephan; Haberl, Helmut; Hostert, Patrick; Jepsen, Martin R.; Kastner, Thomas; Levers, Christian; Lindner, Marcus; Plutzar, Christoph; Verkerk, Pieter Johannes; van der Zanden, Emma H.; Reenberg, Anette
    Future increases in land-based production will need to focus more on sustainably intensifying existing production systems. Unfortunately, our understanding of the global patterns of land use intensity is weak, partly because land use intensity is a complex, multidimensional term, and partly because we lack appropriate datasets to assess land use intensity across broad geographic extents. Here, we review the state of the art regarding approaches for mapping land use intensity and provide a comprehensive overview of available global-scale datasets on land use intensity. We also outline major challenges and opportunities for mapping land use intensity for cropland, grazing, and forestry systems, and identify key issues for future research.