Although subsurface drainage is essential for economical crop production, it can also allow nutrients, such as phosphorus, to bypass the natural filter of the soil and be transported to surface water. Excess phosphorus can cause harmful algal blooms and eutrophication.
Subsurface (tile) drainage is an important part of agriculture, as it improves infiltration, reduces runoff, increases water storage and creates a suitable environment for plant growth through removal of excess water from the farm.
According to researchers, dissolved reactive phosphorus (DRP) loads have increased notably in the Western Lake Erie Basin since the early 2000s, correlating with re-eutrophication in Lake Erie. They found around 65 percent of the increased DRP loads arose from increased DRP delivery. Increased delivery refers to greater phosphorus availability in soil and greater transport due to increased drainage.
Researchers also noted that the implementation of practices to reduce erosion, such as no-till, corresponded with the re-eutrophication of Lake Erie, as well as large increases in DRP loading. Active management practices such as controlled drainage and saturated buffers are designed to conserve water and improve water quality.
Research about drainage water management is being done at Michigan State University. Quantifying the effectiveness of these practices in reducing DRP load is a major component of this research, used to better understand the implementation of management practices to protect surface water quality.
To learn about edge-of-field monitoring and the research being conducted, a Drainage Monitoring Workshop will take place July 19, 2018, in Adrian, Michigan. MSU Extension educators, technicians, agency staff and engineers are encouraged to attend. Sign-in will start at 9:45 a.m. followed by an informational presentation at 10 a.m. that will include low-cost monitoring with a V-notch weir and water grab sampling, as well as high-tech monitoring with an area-velocity sensor and automated water sampling. A field visit to the on-farm experiment to see the equipment will take place in the afternoon.
Some of the instrumentations that will be discussed include the ATMOS-41 Weather Station, HYDROS-21 Water-Level Sensor and TEROS-12 Soil Moisture Sensor (METER GROUP, Pullman, WA). Other instruments are TIENet-350 Area-Velocity Sensor, Signature Data Logger and 6712 Automated Sampler (Teledyne ISCO, Lincoln, NE).
View the Drainage Monitoring Workshop flier for more information, or register online at Drainage Monitoring Workshop.