Soil cylinders from organic tomato field for use in experiments

Soil biology and ecology under organic production is a subject of fundamental and practical interest. Our recent work has investigated rates of nitrogen transformations, soil microbial communities, and field-level changes in nitrogen dynamics in relation to management factors:

• Nitrogen processes in organic and conventional soils: Microbial and plant nitrogen transformations, and soil microbial community composition have been compared between the organic and conventionally managed soils at the Long Term Research in Agricultural Systems (LTRAS) project at University of California at Davis.
•  Real-time PCR for ammonia oxidizers: Development of a real-time PCR method for ammonia-oxidizing bacteria is in progress to determine the relationship between population size and nitrification rates.
• Transition to organic production: Changes in nitrogen pools and microbial activity are being monitored during the transition to organic production by large-scale conventional growers in the Salinas Valley, California, along with changes in other ecological factors.