Configurational crop heterogeneity increases within‐field plant diversity
Audrey Alignier, Xavier Oriol Solé-Senan, Irene Robleño, Bárbara Baraibar, Lenore Fahrig, David Giralt, Nicolas Gross, Jean‐Louis Martin, J. Recasens, Clélia Sirami, G. Siriwardena, Aliette Bosem Baillod, Colette Bertrand, Romain Carrié, Annika L. Hass, Laura Henckel, Paul Miguet, Isabelle Badenhausser, Jacques Baudry, Gérard Bota, Vincent Bretagnolle, Lluis Brotons, Françoise Burel, François Calatayud, Yann Clough, R. Georges, Annick Gibon, Jude Girard, Kathryn E. Lindsay, Jesús Miñano, Scott Mitchell, Nathalie Patry, Brigitte Poulin, Teja Tscharntke, Aude Vialatte, Cyrille Violle, Nicole Yaverscovski, Péter Batáry
Abstract
Abstract Increasing landscape heterogeneity by restoring semi‐natural elements to reverse farmland biodiversity declines is not always economically feasible or acceptable to farmers due to competition for land. We hypothesized that increasing the heterogeneity of the crop mosaic itself, hereafter referred to as crop heterogeneity, can have beneficial effects on within‐field plant diversity. Using a unique multi‐country dataset from a cross‐continent collaborative project covering 1,451 agricultural fields within 432 landscapes in Europe and Canada, we assessed the relative effects of compositional and configurational crop heterogeneity on within‐field plant diversity components. We also examined how these relationships were modulated by the position within the field. We found strong positive effects of configurational crop heterogeneity on within‐field plant alpha and gamma diversity in field interiors. These effects were as high as the effect of semi‐natural cover. In field borders, effects of crop heterogeneity were limited to alpha diversity. We suggest that a heterogeneous crop mosaic may overcome the high negative impact of management practices on plant diversity in field interiors, whereas in field borders, where plant diversity is already high, landscape effects are more limited. Synthesis and applications. Our study shows that increasing configurational crop heterogeneity is beneficial to within‐field plant diversity. It opens up a new effective and complementary way to promote farmland biodiversity without taking land out of agricultural production. We therefore recommend adopting manipulation of crop heterogeneity as a specific, effective management option in future policy measures, perhaps adding to agri‐environment schemes, to contribute to the conservation of farmland plant diversity.