Letter: New buffer law will create problems
To the editor:
The implementation of a new law will damage ecosystems in Minnesota by elevating phosphate levels in Minnesota waters. Phosphate has been identified as the most important cropland nutrient to prevent from reaching surface water. High phosphate levels cause algae blooms that deplete oxygen and cause fish kills.
The Buffer Strip law requires up to 50 feet of perennial vegetation between cropland and ditches or lakes. As this vegetation decays, it creates phosphates. Snowmelt dissolves these phosphates and carries them directly into ditches. Fertilizer is frozen in tilled soil, so the buffer strips do nothing but damage in the spring.
One destructive part of this law is the requirement of leveling berms at the perimeter of a field and planting vegetation. Spring rains and flooding in flat country will carry particulate phosphates as well as dissolved phosphates into ditches and lakes. Phosphate contamination in these waters will increase exponentially because farmers will replace the lost phosphates with additional fertilizer.
Studies describing buffer strip phosphate runoff include, "Soluble Phosphorus Losses in Spring Snowmelt Runoff in the Northern Great Plains," "Evaluating the potential contribution of vegetation as a nutrient source in snowmelt runoff," and UofM's "Phosphorus: Transport to and availability in surface waters."
Buffer strips work in erodible cropland with steep slopes and light soil, such as the Minnesota River valley, where buffers exist. During erosion, phosphate is carried with the eroded soil as a solid. Little cropland in Minnesota falls into this category.
Buffer strip implementation begins this spring! Legislators are working to repeal buffer strip statute 103f.48. Please contact your legislator to voice opposition. Minnesota House and Senate contact information can be found at the Minnesota State Legislature website under Member Information.
Mike Van Horn