Evaluating Spatial and Temporal Changes in Dung Distribution between Grazing Strategies Using an Unmanned Aerial Vehicle (UAV).

Utilization of different grazing management strategies may result in different patterns of nutrient return to the soil based on urine and dung deposition, and these deposition patterns may, in turn, affect the overall nutrient cycling dynamics of a pasture. However, assessing variation in dung distribution is challenging due to the time and resources needed to effectively monitor large areas of land and then accurately map distribution patterns over time. High spatial resolution aerial imagery presents an innovative method for gathering dung distribution data and monitoring temporal changes in distribution. In this study, an unmanned aerial vehicle (UAV) fitted with a 4-band sensor was used to capture images of pastures located in a Nebraska Sandhills meadow which utilized different grazing strategies. Image capture was performed throughout the grazing season to assess differences in dung distribution both spatially and temporally, within and between treatments. Dung pats were identified based on reflectance patterns and then mapped, and distribution patterns between treatments were then compared using spatial analysis techniques within a GIS.