The Agricultural Policy Environmental eXtender (APEX) model was developed by the Blacklands Research and Extension Center in Temple, Texas. APEX is a flexible and dynamic tool that is capable of simulating a wide array of management practices, cropping systems, and other land use across a broad...

A model of manure utilization is developed and applied to four types of transportable manure. Model results highlight important response differences among manure types and generally illustrate the diseconomies of manure production. For example, as manure production increases, manure value...

The development of the field-scale Erosion Productivity Impact Calculator (EPIC) model was initiated in 1981 to support assessments of soil erosion impacts on soil productivity for soil, climate, and cropping conditions representative of a broad spectrum of U.S. agricultural production regions....

An integrated modeling system has been constructed for the Upper North Bosque River Watershed (UNBRW) in Erath and Hamilton Counties, Texas, to simulate the movement of nutrients from dairy waste disposal fields. The authors describe the environmental component of that modeling system, focusing...

Assessing the effects of alternative policies that regulate nonpoint pollution from concentrated animal feeding operations (CAFOs) requires insight into the interactions of livestock production practices, waste management technologies, and their impacts on the environment. CAFOs have been...