Landscape–Scale Water Balance of Cotton Fields.

Information on the temporal and spatial distribution of the components of the water balance of a production field is necessary to manage agronomic inputs. Furthermore, factors that determine crop yield require knowledge of the energy, water, nutrient and carbon balance and their interaction. The integration of crop simulation models with geographic information data on soil and elevation, real-time weather, and management information systems have provided the tools to explore the dynamics of crop production. These interactions can be quantified at a 5-10 m scale and then integrated to the field–scale, i.e., landscape, for their application. For the last five years we have applied the Precision Agricultural Landscape Modeling System (PALMS) developed by John Norman and co-workers at the University of Wisconsin to explore cotton production under limited irrigation and in a semiarid climate. The goal is to use these models to provide a decision-support framework to manage agronomic inputs to maximize crop yield.