Increasing crop heterogeneity enhances multitrophic diversity across agricultural regions

Summary, in English

Agricultural landscape homogenization has detrimental effects on biodiversity and key ecosystem services. Increasing agricultural landscape heterogeneity by increasing seminatural cover can help to mitigate biodiversity loss. However, the amount of seminatural cover is generally low and difficult to increase in many intensively managed agricultural landscapes. We hypothesized that increasing the heterogeneity of the crop mosaic itself (hereafter “crop heterogeneity”) can also have positive effects on biodiversity. In 8 contrasting regions of Europe and North America, we selected 435 landscapes along independent gradients of crop diversity and mean field size. Within each landscape, we selected 3 sampling sites in 1, 2, or 3 crop types. We sampled 7 taxa (plants, bees, butterflies, hoverflies, carabids, spiders, and birds) and calculated a synthetic index of multitrophic diversity at the landscape level. Increasing crop heterogeneity was more beneficial for multitrophic diversity than increasing seminatural cover. For instance, the effect of decreasing mean field size from 5 to 2.8 ha was as strong as the effect of increasing seminatural cover from 0.5 to 11%. Decreasing mean field size benefited multitrophic diversity even in the absence of seminatural vegetation between fields. Increasing the number of crop types sampled had a positive effect on landscape-level multitrophic diversity. However, the effect of increasing crop diversity in the landscape surrounding fields sampled depended on the amount of seminatural cover. Our study provides large-scale, multitrophic, cross-regional evidence that increasing crop heterogeneity can be an effective way to increase biodiversity in agricultural landscapes without taking land out of agricultural production.

• Författare: Clélia Sirami; Nicolas Gross; Aliette Bosem Baillod; Colette Bertrand; Romain Carrié; Annika Hass; Laura Henckel; Paul Miguet; Carole Vuillot; Audrey Alignier; Jude Girard; Péter Batáry; Yann Clough; Cyrille Violle; David Giralt; Gerard Bota; Isabelle Badenhausser; Gaëtan Lefebvre; Bertrand Gauffre; Aude Vialatte; François Calatayud; Assu Gil-Tena; Lutz Tischendorf; Scott Mitchell; Kathryn Lindsay; Romain Georges; Samuel Hilaire; Jordi Recasens; Xavier Oriol Solé-Senan; Irene Robleño; Jordi Bosch; Jose Antonio Barrientos; Antonio Ricarte; Maria Ángeles Marcos-Garcia; Jesús Miñano; Raphaël Mathevet; Annick Gibon; Jacques Baudry; Gérard Balent; Brigitte Poulin; Françoise Burel; Teja Tscharntke; Vincent Bretagnolle; Gavin Siriwardena; Annie Ouin; Lluis Brotons; Jean Louis Martin; Lenore Fahrig
• Avdelning/ar: Centrum för miljö- och klimatvetenskap (CEC); BECC: Biodiversity and Ecosystem services in a Changing Climate
• Publiceringsår: 2019-08-13
• Språk: Engelska
• Sidor: 16442-16447
• Publikation/Tidskrift/Serie: Proceedings of the National Academy of Sciences of the United States of America
• Volym: 116
• Issue: 33
• Länkar: http://dx.doi.org/10.1073/pnas.1906419116
• Dokumenttyp: Artikel i tidskrift
• Förlag: National Academy of Sciences
• Ämne: Agricultural Science
• Nyckelord: Biodiversity; Complementation; Crop mosaic; Farmland; Landscape; Multitaxa
• Status: Published
• ISBN/ISSN/Övrigt: ISSN: 0027-8424