Assessing social–ecological coupling: Agriculture and hypoxia in the Gulf of Mexico Stefanie Hufnagl-Eichiner a, *, Steven A. Wolf b , Laurie E. Drinkwater c a Cornell University, Department of Natural Resources, 302 Fernow Hall, Ithaca, NY 14853, United States b Cornell University, Department of Natural Resources, 124 Fernow Hall, Ithaca, NY 14853, United States c Cornell University, Department of Horticulture, 124 Plant Science, Ithaca, NY 14853, United States 1. Introduction Analysis and enhancement of ‘‘coupling’’ of human and biophysical systems has emerged as a leading theme in the study of global environmental change. We find the concept of coupled social and ecological systems promising in that it allows us to elide the rigid separation that emerges from consideration of humans as outside of nature (Cronon, 1996). But as an analytical concept that can support empirical research, the concept has not been adequately developed (Spaargaren et al., 2006). There is a need to operationalize theories of social–ecological coupling in order to advance the field (Liu et al., 2007) and base this operationalization on shared frameworks that allow for the accumulation of knowledge from different disciplines (Ostrom, 2009). A defining feature of a coupled system is the interactions that occur between social and biophysical components at multiple spatial and temporal scales (Norgaard, 1994). If feedback loops between subsystems lead to environmental or socioeconomic degradation, or if there are inadequate feedbacks, we consider this to be a case of maladaptive coupling. For example, using fossil fuels to convert atmospheric nitrogen to plant-available forms has enabled previously impossible rates of food production and corresponding growth of human population. In many settings, previous scarcity of nitrogen has given way to nitrogen pollution (Vitousek et al., 1997). Excess nitrogen in soil, water, and the atmosphere is directly linked to detrimental human health effects, as well as to socioeconomic and ecological degradation (Turner et al., 1998; Zimmerman and Nance, 2001; Townsend et al., 2003; Oguz and Gilbert, 2007). The lack of potent social and technical response to the risks of doubling of the mobile nitrogen in the global ecosystem is a prominent example of dysfunctional social– ecological feedbacks (Galloway and Cowling, 2002). In contrast, adaptive coupling occurs when linkages between the environ- mental and social subsystems support societal responses that prevent environmental degradation and maintain the integrity of the biosphere. This paper integrates the perspectives of natural and social scientists to study a specific coupled system. The goal of this study Global Environmental Change 21 (2011) 530–539 ARTICLE INFO Article history: Received 22 December 2009 Received in revised form 16 November 2010 Accepted 23 November 2010 Available online 22 December 2010 Keywords: Coupled system Social–ecological interface Targeting Public agricultural research Mississippi River Gulf of Mexico ABSTRACT Analysis and enhancement of ‘‘coupling’’ of social–ecological systems (SES) has emerged as a leading theme in sustainability studies. However, as an analytical concept that can support empirical research, coupling has not been adequately developed. This study synthesizes concepts from environmental sociology and ecological sciences to derive three criteria to assess adaptive coupling of an SES: prevention orientation, spatial targeting and temporal targeting. We apply our criteria to the case of nitrogen pollution from agriculture in the Mississippi River Basin (MRB) and resulting hypoxia in the Gulf of Mexico. We analyzed the federal agricultural research and development portfolio to assess the character of investments in knowledge creation and how patterns of investment have changed over time. While superficial assessment of the data suggests that public spending on nitrogen relevant research constitutes a substantive response to the problem of Gulf hypoxia, disaggregating the data highlights an ineffectual response. Specifically, we find that spatial and temporal targeting of investment of socioeconomic resources in the MRB is poorly aligned with the nature of ecological risks confronting the region. In addition to this policy relevant result, our study highlights the importance of geographically referenced data and attention to relevant scales of analysis. Further, the paper demonstrates opportunities to advance concepts and empirical understanding of social–ecological coupling through interdisciplinary research on interfaces that mediate interactions in SES, for example publicly funded research aimed at agricultural practice and environmental conservation in the MRB. ß 2010 Elsevier Ltd. All rights reserved. * Corresponding author. Tel.: +1 607 255 6904; fax: +1 607 255 0349. E-mail address: sh339@cornell.edu (S. Hufnagl-Eichiner). Contents lists available at ScienceDirect Global Environmental Change journal homepage: www.elsevier.com/locate/gloenvcha 0959-3780/$ – see front matter ß 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.gloenvcha.2010.11.007