Evaluation of Sampling Protocol for i-Tree Eco: A Case Study in Predicting Ecosystem Services at Auburn University

A study of plot sampling intensity from a 100% i-Tree Eco inventory on the Auburn University Campus.

"Auburn University (Auburn, Alabama, U.S.) was used as a site for a case study evaluating the standard plot sampling protocol for i-Tree Eco. A 100% tree inventory of the managed areas of campus was conducted in 2009–2010 and provided a complete data set for the evaluation. Air pollution removal, carbon storage, and carbon sequestration were the ecosystem services examined. Total tree population was also utilized for this assessment to provide a comparison to i-Tree Eco protocol. To achieve an estimate with a ±10% allowable error of the total campus value, 622 plots (0.04 ha each) with at least one tree present would need to be inventoried for air pollution removal, 870 plots for carbon storage, 483 plots for carbon sequestration, and 258 plots for number of trees, as opposed to the standard i-Tree Eco protocol of 200 plots. This study provides a first step in evaluating i-Tree Eco sampling protocol; however, efforts testing these results at sites throughout the southern United States are needed to provide the most accurate estimate of plot numbers necessary for predicting ecosystem services of urban forests." [Abstract]