SYMP 14-3
Integrating knowledge of microbial ecology toward resilient and sustainable food systems
Soil biological communities, and plant-microbial symbioses, are behind much that we take for granted in the functioning of agricultural and natural ecosystems: the availability of plant nutrients, creation of soil structure, accumulation of soil organic matter, plant disease suppression, decomposition of pesticides. Continually evolving technologies are making it more and more possible to link the diversity and activities of the rich and diverse communities living below ground. In longterm field trials at the Russell Ranch Sustainable Agriculture Facility at UC Davis, soil communities have diverged under organic versus conventional management, in farmed versus unmanaged or grassland plots, and under different crops. As managers of agricultural systems, we have barely scratched the surface in understanding and promoting microbial processes that support plant health and productivity, reduce environmental degradation and increase sustainability. Soil organisms have considerable, untapped, potential to compensate for external inputs of fossil fuel-based fertilizers and pesticides that are substantially reducing the sustainability of agricultural ecosystems and degrading the environment. In most cases, the solutions are not (or even) as simple as just adding the right organisms but rather require an understanding of microbial needs in order to manipulate their environment to provide limiting resources or spatially bring together organisms and their substrates.
Results/Conclusions
I will review research on examples of biologically-based approaches and tools to enhance agricultural sustainability and resilience through manipulation of microbial biomass, microbial community composition, plant-microbe relationships, and location of substrates, nutrients and water. I will discuss differences in how farmers and researchers view soil biology (results of a survey) and discuss major questions and key gaps in our understanding of how to promote beneficial and repress detrimental activities of soil populations and communities. Finally we will discuss recent developments that show the greatest promise and feasibility in shifting some of the burden of growing food from external inputs to the below communities in agroecosystems.