Measuring Grazing Impacts on Stream Condition Using Remote Sensing Vegetative Indices

Effective management of stream side riparian areas requires monitoring the effects of livestock in these zones.  Measurements of grazing impacts are usually collected as short term measures which are ultimately related to longer term effects in overall stream condition.  Most managers seek to balance livestock use with maintaining the riparian ecosystem.  Monitoring livestock use is difficult due to the large area under grazing pressure.  Current monitoring strategies face challenges including subsampling, a variety of monitoring methods, and budget constraints.  Remotely sensed data provides the opportunity to evaluate a much larger area in a uniform manner.  By using a remotely sensed vegetative index to account for changes in vegetation cover we seek to develop a tool for landscape wide examination of livestock impacts on riparian areas.  This would allow for locations to target with on ground subsampling after examining a large extent.  The large amount of previously collected imagery allows for an examination of the multiyear impacts of grazing.  This approach can help managers identify impacts of grazing over a large area, with regular time interval updates. By regularly identifying highly impacted areas management decisions could be more spatially focused and prioritized throughout the grazing season.