This relationship can
Ranchers in the Northern Great Plains (NGP) make difficult economic decisions every spring. Ranchers must predict the amount of forage their pastures will produce in order to set stocking rates for the coming growing season [1]. These forage production estimates are based largely on a combination of guess work and expert knowledge that might be heavily influenced by the successes or failures of the previous growing seasons.Annual forage production is significantly correlated with two factors in non-irrigated, semi-arid rangelands like those in the NGP: the amount of water stored in the soil preceding the growing season and the amount of precipitation that falls during the growing season [2, 3].

It is not feasible to predict the amount of rain that will fall in an upcoming summer.

It might be possible, however, to model and map the spatial distribution of spring, pre-growing season soil water content.Spring soil water content maps are a potential precision range management application. Though precision range management is not at the stage of application of precision farming, there is a growing collection of ranchers that are becoming technologically savvy. These ranchers are interested in using GPS, GIS, and remotely sensed imagery for ranch management, resource inventory, and conservation purposes. Substantial challenges have existed, however, for applying satellite image based precision agriculture to range management [see, e.g., 4, 5].

Moderate-resolution imagery, which is generally needed to cover the geographic extents involved in range management, for example, has generally been inadequate to measure many of the factors necessary to evaluate range condition. Recent developments, however, have shown this type of imagery useful for evaluating factors related to biomass condition and percent of bare soil, raising hope for increased development of precision Anacetrapib range management techniques [4]. Development of a method for modeling and mapping spring soil water content that implements these geospatial tools would both aid ranchers interested in using precision agriculture techniques for management tasks such as setting stocking rates and contribute to the advancement of precision agriculture and precision conservation in ranching culture.

A precision range modeling application must Cilengitide be based on publicly available data and be easily implemented at a ranch scale to be useful. Semi-arid rangeland spring soil water content can be conceptually modeled using a water balance approach. Inputs (precipitation and runon) must equal outputs (evapotranspiration, drainage, and runoff) minus change in storage (soil water content).