Tillage Effects on Soil Health and Water Dynamics in the Conversion of Grassland to Row Crops.

The western South Dakota landscape is a mosaic of land uses; a delicate balance dominated by grassland and wheat production. Between 2008 and 2012, over 1 million acres of grassland were converted to wheat in the northern Great Plains. Currently, as much as 5% of the stateÕs grassland is being converted to cropland each year. Land conversion from grassland to row crops is happening at an alarming rate, yet little research exists documenting the short-term effects to soil health immediately after grassland conversion. The fundamental research question guiding this research was: ÒHow do ecosystem processes change when native rangeland is converted to annual crops?Ó To answer this question, native grassland in western South Dakota was converted to spring and winter wheat either through conventional tillage or no-till. The objective of this research was to set up a field site equipped with a sensor network to continuously monitor specific indicators such as soil water content and temperature for long-term ecosystem change while documenting the short-term effects following initial land conversion. Results will be presented with a focus on the short-term changes to the carbon and nitrogen cycles along with changes to the soil microbiome and key enzymes.