Web-based Calculator to Help Growers Nationwide Precisely Manage Cover Crops, Nitrogen Fertilizer
Growing among the remains of harvested corn stalks, these green shoots of rye take up excess nutrients in the soil. When the new crop is planted in the spring, the rye will be killed and left to release the nutrients back to the soil for crop growth.
Image Credit: Edwin Remsberg
A $1.2 million grant from the U.S. Department of Agriculture's Natural Resources Conservation Service will support a University of Maryland researcher’s work to help farmers across the United States make informed decisions about fertilizer use and reduce greenhouse gas emissions.
Brian Needelman, a professor in the Department of Environmental Science and Technology, and his colleagues are developing a web-based tool to solve the problem of nitrogen from excess fertilizer in farm fields that can pollute waterways while contributing to climate change. When bacteria digest nitrogen, the process releases nitrous oxide, third most-common greenhouse gas.
To combat this issue, farmers often plant cover crops in the off season to help absorb some of the excess nitrogen, which is released back into the ground in the spring when farmers kill off the cover crop and plant their cash crop. This reduces the amount of commercial fertilizer farmers need to apply.
However, determining how much nitrogen a cover crop takes up and how much nitrous oxide is emitted can be difficult due to various factors such as climate, weather and soil conditions.
Needelman and his colleagues aim to address this challenge by integrating satellite imagery of farm fields with location-specific data on soil composition, rainfall, temperature and other climate factors to more precisely predict the real-time conditions of cover crops on fields and calculate the nitrogen available for cash crops during planting. The tool, called the Cover Crop Nitrogen Calculator, will provide farmers with real-time, site-specific information about the performance of cover crops and estimates of greenhouse gas emissions.
