Assessing the Link Between Soil Health and Water Quality in the St. Joseph Watershed.

Recently, soil health has become a popular topic of interest amongst researchers and producers. It is believed that a healthier soil contributes to not only a higher production potential, but also to improving environmental concerns, such as water quality. The main focus of this study is to assess the relationship between soil health and water quality in agricultural fields. Composite soil samples from two depths (0-5cm, 5-20cm) were collected from fifteen sites in three fields located in the St. Joseph Watershed in northeastern Indiana. The current crop in each of the fields is soybean and the tillage systems are no-till, rotational, and conventional. In order to determine the overall soil health for each of these fields, a series of physical tests (bulk density, aggregate stability, particle size distribution), biological tests (organic matter content, potential nitrogen mineralization, CO₂ respiration) and chemical tests (pH/EC, total carbon and nitrogen, extractable nutrients) are being conducted. Water quality sensors installed in these fields collect both surface runoff and tile drainage, which are analyzed for sediment and nutrient concentrations. The water data results will be used in conjunction with the results from the soil quality tests, in order to determine if soil health has an impact on water quality. If soil health provides a reasonable link to water quality, it will be possible to use conservation practices to improve soil properties, thus ultimately improving water quality.