Conceptual and Empirical Approaches to Mapping and Quantifying Land-Use Intensity

Abstract

Land use is a pervasive driver of change in the earth system (Steffen et al., Ambio 36:614–621, 2007; Turner et al., Proceedings of the National Academy of Sciences of the United States of America 104:20666–20671, 2007). Today, the majority of the ice-free terrestrial surface has been affected in one way or another by human land use (McCloskey and Spalding, Ambio 18:221–227, 1989; Sanderson et al., BioScience 52:891–904, 2002), and since the beginning of agriculture, more than one third of all pristine terrestrial ecosystems have been converted to human-controlled, permanently managed ecosystems with fundamentally altered ecological characteristics (Erb et al., Journal of Land Use Science 2:191–224, 2007). By using the land, human societies alter structures and processes in ecosystems and thereby substantially affect global land cover, biodiversity, biogeochemical cycles of carbon, water, nitrogen, and many other patterns and processes, with far-reaching consequences for ecosystems and human well-being (Millennium Ecosystem Assessment, Ecosystems and human well-being: Current state and trends, 2005). Land use, on the one hand, provides the basis of nutrition, an array of resources and many essential ecosystem services to society. On the other hand, land use is increasingly jeopardising ecosystem functioning and thus threatens the biophysical basis of humanity. This fundamental trade-off related to land use leads to the emergence of an interdisciplinary research agenda, land-system science (Global Land Project, Science plan and implementation strategy. IGBP Report No. 53/ IHDP Report No. 19, 2005), which seeks to improve the observation of land changes as well as the understanding of these changes in a systemic context, including the interactions and feedback loops among social and natural systems (Turner et al., Annals of the Association of American Geographers, 67, 384–396, 2007).