Final Report: Patch-burn Grazing as a Tool for the Ecological Management of Invasive Species and Restoration of Carbon Sequestration and Ecosystem Processes in Working LandscapesEPA Grant Number: SU834719
Title: Patch-burn Grazing as a Tool for the Ecological Management of Invasive Species and Restoration of Carbon Sequestration and Ecosystem Processes in Working Landscapes
Investigators: Engle, David M , McGranahan, Devan Allen , Veenstra, Jessica J
Institution: Iowa State University , Oklahoma State University
EPA Project Officer: Nolt-Helms, Cynthia
Project Period: August 15, 2010 through August 14, 2011
Project Amount: $10,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2010) RFA Text | Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , P3 Challenge Area - Agriculture , P3 Awards , Sustainability
Exotic species invasions threaten the sustainability of grazing systems in working grassland and rangeland landscapes. We propose a novel grazing management strategy that replicates natural ecological processes to reduce invasive species abundance while still providing income from grazing. Our strategy is an ideal example of appropriate technology because it is an alternative to herbicide application, which is economically and environmentally costly. Furthermore, reducing invasive species abundance restores habitat and might improve carbon sequestration. We will use existing partnerships with local farmers to demonstrate and develop this grazing management system.
We found that the proportion of native species in the plant community was negatively correlated with the abundance of the invasive tall fescue, and that three states of vegetation degradation oriented along this linear relationship. However, root mass did not vary among the three degradation states, except among the 0-20 cm depth, in which soil cores from High Invasion plots had significantly lower root mass than plots in both the Low Invasion and Uninvaded states.
Tall fescue abundance did not vary significantly between the PBG treatment and a control group of tracts. While the trend was for the maximum abundance of tall fescue to decline within the PBG group, a large amount of variation within both groups made the trend statistically insignificant in a linear mixed-effect regression model. There was a significant year effect in the model.
We can qualitatively describe the benefits of PBG in terms of people, prosperity, and planet in the following terms: PBG supports people and prosperity through the enhancement of the local livestock culture by accommodating cattle grazing on conservation areas, and by maintaining grassland condition or reversing grassland degradation which sustains grazing productivity. PBG contributes to the sustainability of the planet by eliminating the risk of water contamination due to pesticide or fertilizer pollution, as no pesticides or fertilizers were applied or determined to be necessary. These impacts clearly contribute to improved quality of life by supporting economic and social culture, enhancing the diversity and productivity of agricultural landscapes, and reducing pollution in the environment.