Environmental Sciences Commons^™

Spatiotemporal Variation In Vegetation Structure Resulting From Pyric-Herbivory, Sherry Leis, Lloyd W. Morrison, Michael D. Debacker

The Prairie Naturalist

Pyric-herbivory is a process that is widely assumed to create greater habitat heterogeneity in grasslands at the landscape scale than could be achieved by either fire or grazing alone. Yet, few studies have actually quantified the effects of pyric- herbivory on vegetation structure within layers of the grass canopy. Here we quantify the effects of pyric-herbivory on a pasture at Tallgrass Prairie National Preserve in Kansas. We subdivided the pasture into three patches and burned one patch each year in a three-year rotation. We estimated visual obstruction for 25-cm strata and recorded maximum vegetation height. We found that recently burned …

Spatial Heterogeneity Across Five Rangelands Managed With Pyric-Herbivory, Devan Allen Mcgranahan, David M. Engle, Samuel D. Fuhlendorf, Stephen L. Winter, James R. Miller, Diane M. Debinski

School of Natural Resources: Faculty Publications

1. Many rangelands evolved under an interactive disturbance regime in which grazers respond to the spatial pattern of fire and create a patchy, heterogeneous landscape. Spatially heterogeneous fire and grazing create heterogeneity in vegetation structure at the landscape level (patch contrast) and increase rangeland biodiversity. We analyzed five experiments comparing spatially heterogeneous fire treatments to spatially homogeneous fire treatments on grazed rangeland along a precipitation gradient in the North American Great Plains.

2. We predicted that, across the precipitation gradient, management for heterogeneity increases both patch contrast and variance in the composition of plant functional groups. Furthermore, we predicted that …