Location: Plant Science ResearchTitle: Grassland-cropping rotations: An avenue for agricultural diversification to reconcile high production with environmental quality Author
|Lemaire, Gilles - Institut National De La Recherche Agronomique (INRA)|
|Gastal, Francois - Institut National De La Recherche Agronomique (INRA)|
|Chabi, Abad - Institut National De La Recherche Agronomique (INRA)|
Submitted to: Environmental Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/6/2015
Publication Date: 6/13/2015
Citation: Lemaire, G., Gastal, F., Franzluebbers, A.J., Chabi, A. 2015. Grassland-cropping rotations: An avenue for agricultural diversification to reconcile high production with environmental quality. Environmental Management. 56:1065-1077.
Interpretive Summary: Agricultural production and environmental protection need to be balanced to meet food security and sustainability goals. An ARS scientist at the Plant Science Research Unit in Raleigh North Carolina teamed with scientists from the National Institute for Agronomic Research (INRA) in Lusignan France to provide a review and perspective on how integrated crop-livestock systems might be a viable option for sustainable intensification of agriculture by enhancing diversity of agricultural systems and not simplification. Loss of diversity within agricultural systems at field, farm and landscape scales was identified as a key issue dividing the approaches, and therefore, a solution proposed is for integrated crop-livestock systems to increase diversity at various spatial and temporal scales so that high production and environmental quality can be simultaneously achieved. To increase diversity, local and regional integration of cropping with livestock systems is suggested, which would allow (i) better regulation of biogeochemical cycles and decreased environmental fluxes to the atmosphere and hydrosphere through spatial and temporal interactions among different land-use systems; (ii) a more diversified and structured landscape mosaic that would favor diverse habitats and trophic networks; and iii) greater flexibility of the whole system to cope with potential socio-economic and climate change induced hazards and crises. Integrated crop-livestock systems could be a key form of ecological intensification needed for achieving future food security and environmental sustainability.
Technical Abstract: A need to increase agricultural production across the world to ensure continued food security appears to be at odds with the urgency to reduce the negative environmental impacts of intensive agriculture. Around the world, intensification has been associated with massive simplification and uniformity at all levels of organization, i.e. field, farm, landscape and region. Therefore, we postulate that environmental impacts of modern agriculture are due more to an excess of uniformity than to an excess of productivity. Thus by enhancing diversity within agricultural systems it should be possible to reconcile high quantity and quality of food production with environmental quality. Intensification of livestock and cropping systems separately within different specialized regions inevitably leads to unacceptable environmental impacts because of the overly uniform land use system in intensive cereal areas and excessive N loads in intensive animal areas. The capacity of grassland ecosystems to couple C and N cycles through microbial-soil-plant interactions as a way for mitigating the environmental impacts of intensive arable cropping system was analyzed in different management options: grazing, cutting, and ley duration, in order to minimize trade-offs between production and the environment. We suggest that integrated crop-livestock systems are an appropriate strategy to enhance diversity. Sod-based rotations can temporally and spatially capture the benefits of leys for minimizing environmental impacts, while still maintaining periods and areas of intensive cropping. Long-term experimental results illustrate the potential of such systems to sequester C in soil and to reduce and control N emissions to the atmosphere and hydrosphere.