Plant community dynamics in agricultural and successional fields

Understanding the drivers and consequences of diversity and productivity in plant communities remains a central challenge in ecological research (Thompson et al. 2001, Mittelbach 2012). Interest in how the diversity and composition of plant communities regulate ecological processes and ecosystem services that different ecosystems provide has expanded over the past two decades (Loreau et al. 2001). This question has remained relatively unexplored in agricultural systems—particularly the annual row crops that supply much of the world’s food (Power 2010). This is likely because factors known to influence weed and crop production—such as soil fertility, precipitation, and pests (weeds, pathogens, and insects)—are primarily managed with external inputs (fertilizer, irrigation, and pesticides) rather than by relying on ecological processes (Robertson and Swinton 2005). Growing concerns about the negative environmental impacts of using external inputs to sustain crop productivity have stimulated interest in the development of an ecological framework for agricultural management (Robertson and Swinton 2005, Swinton et al. 2006, 2007, Robertson and Hamilton 2015, Chapter 1 in this volume). In addition to crop yield, an ecological framework would consider other ecosystem services that can be managed and enhanced both in the field and in surrounding landscapes (Swinton et al. 2006, 2007, Power 2010). Plant diversity and composition are likely to play an important role in the actualization and sustainability of these services, particularly from landscapes that surround crop fields (Power 2010, Egan and Mortensen 2012). Row-crop systems are designed and managed to maintain the dominance of a particular species (the crop), with the goal of maximizing productivity (crop yield). Although row-crop systems can provide an array of other ecosystem services (Swinton et al. 2006, 2007, Power 2010), promotion or enhancement of these Gross, K. L., S. Emery, A. S. Davis, R. G. Smith, and T. M. P. Robinson. 2015. Plant community dynamics in agricultural and successional fields. Pages 158-187 in S. K. Hamilton, J. E. Doll, and G. P. Robertson, editors. The Ecology of Agricultural Landscapes: Long-Term Research on the Path to Sustainability. Oxford University Press, New York, New York, USA.