A decade of change in nutrient management: a new nitrogen index

Excerpt

The goal of nutrient management is to optimize nutrient's advantages, and minimize their disadvantages. Nutrient use efficiency has to consider the effect and link between a field's soil, the crop, the weather, and hydrology, along with the practices being used on the property, such as irrigation, fertilizer, and manure management. This is a tall order. In addition, a nutrient manager's decisions have the potential to increase the use efficiency of one element, while simultaneously reducing the efficiency of a second nutrient, increasing its losses (Delgado and Lemunyon, 2006). Luckily, a new nitrogen index tool has been developed to coincide with multiple nutrients in varying scenarios. The goal to develop a nitrogen index is not new, and for the past twenty years various nitrogen indexes have been built (Follett et al., 1991, Shaffer and Delgado, 2002). This “new” index is based on the previous work, but is considered new for three reasons: 1) expanded/combined information, 2) international input, and 3) the ease of use while connecting to phosphorus indexes and simulation models. The Nitrogen Index Tool version 1.0 builds also on the modeling software, “Nitrate Leaching and Economic Analysis Package …