My research at Virginia Tech for my PhD is focused on using cover crops to improve soil health and increase nutrient cycling. I am working on a long-term rotation experiment that compares traditional field crop rotations with rotations that include monoculture and diverse cover crops.
Cover crops are plants when the field would normally be empty after the harvest. Instead of leaving the field empty over the winter, a farmer can plant cover crops to “cover” and protect the soil. But these cover crops can have additional benefits, like capturing extra nutrients, enriching the soil with carbon and nutrients, feeding soil insects and animals, reducing weeds and more.
I want to find out if farmers in eastern Virginia can use cover crops to improve their soil health, reduce the amount of fertilizers they need and increase crop yield.
Figure 2. Research farm at Puyallup Research and Extension Center
I worked with the Organic Farming Systems and Nutrient Management Program at the Puyallup Research and Extension Center in Washington State. We grew organic vegetable crops and were trying to use reduced tillage in organic farming. My research focused on how reducing tillage in organic vegetable farming can help lower greenhouse gas emissions.
I measured carbon dioxide and nitrous oxide emissions using two different methods: static, closed chamber method described in the GRACEnet protocol and the dynamic, closed chamber method using an infrared gas analyzer.
Figure 3. Collecting gas samples using the static, closed-chamber method.
We found that reduced tillage had lower greenhouse gas emissions than more intensive, conventional tillage in the spring. But in the fall, reduced tillage had higher emissions than conventional tillage.