Cover Cropping Impacts on Arbuscular Mycorrhizal Fungi and Soil Aggregation.

Cover crops are a management tool which can extend the period of time that a living plant is growing and conducting photosynthesis. This is critical for soil health, because most of the soil organisms, particularly the arbuscular mycorrhizal fungi, are limited by carbon. Research, on-farm, and demonstration plot studies indicate that continuous cropping (i.e. eliminating crop-fallow) and inclusion of cover crops or green manure crops enhance mycorrhizal activity, glomalin production, and soil aggregation. Increases in mycorrhizal activity increase nutrient cycling and nutrient acquisition and improve plant resiliency under changing climatic conditions. In addition, soil aggregation creates soil with numerous stable pores for better water infiltration and water-holding capacity, and soil within aggregates also resists wind and water erosion. Finally, because cover crops increase the overall input of carbon into the soil and carbon compounds, even labile ones, within aggregates are less susceptible to decomposition, this may make a substantial difference in soil carbon storage.