DEPARTMENT OF PLANT SCIENCE AND LANDSCAPE ARCHITECTURE
Fall 2019 Seminar Series
Our Phosphorus Accumulation Problem: An Interactive Discussion
by Tom F. Morris, Professor, UConn Plant Science and Landscape Architecture
The state of Connecticut recently provided incentives for dairy farmers to establish anaerobic digesters on their farms and to import food waste to make the digesters efficient with the goal to reduce the incineration of food waste. The legislators, however, did not understand that importing food waste onto dairy farms imports phosphorus, and many dairy farms in Connecticut, like many livestock farms in the US, already have excess phosphorus in their soils. Connecticut dairy farmers are eager to buy anaerobic digesters because the state incentives and subsidies from the Natural Resources Conservation Service (NRCS) make the digesters profitable, and many farms are struggling financially due to low milk prices. Farmers, unfortunately, cannot buy digesters until there is a solution to the problem of phosphorus accumulation in agricultural fields because the NRCS subsidies, which make the digesters profitable, are unavailable to farmers unless they can land apply the phosphorus without accumulating excess. The accumulation of phosphorus on livestock farms is one unintended consequence of their need to import feed from grain farms. Livestock remove only about 30% of the phosphorus from the imported feed grains with the remaining 70% residing in the manure, which is spread on fields, typically on fields nearby the barns. This accumulation of phosphorus was not considered a problem until recent research established threshold values for phosphorus in soils. When the threshold values are exceeded, dissolved phosphorus leaves fields via runoff and leachate in concentrations that pollute water bodies. About 35% of the fields farmed by Connecticut dairy farmers exceed the threshold for phosphorus. These fields pollute water bodies every time rainfall generates runoff and leachate.
Attend this seminar and explore this social, economic and environmental conundrum in a discussion of these topics while playing the role of a farmer, fertilizer dealer, regulator or extension educator.
Date: Friday, Sept 13
Time: 12-1 pm
Room: W.B. Young 001
Join us for pizza!
Upcoming seminars: http://psla.uconn.edu/SeminarsFall2019.pdf
For more information, contact: PSLA at psla@uconn.edu