Gainesville Urban Forest Effects Project

Introduction

Like native forests, the urban forest contains a variety of tree species of different sizes and shapes. Unlike native forests, we know very little about how the urban forest functions and changes over time. Knowing how the urban forest changes over time is important not only for creating a livable environment, but also for managing catastrophic disasters such as hurricanes.

In 2005, we initiated the Urban Forest Effects Project in Gainesville, FL. The primary objective of this project is to monitor how the urban forest changes over time in a small urban city in the South. The project uses the protocol developed for the Urban Forest Effects model (UFORE) to determine species composition, diameter distribution, tree health, species diversity, and native and non-native species distribution.

UFORE is a computer model developed to help managers and researchers quantify urban forest structure and its functions. UFORE uses standardized field data from randomly located plots, and local hourly air pollution and meteorological data to quantify urban forest structure. The model also quantifies how that structure affects carbon sequestration and air pollution concentrations.

Research Methods

Data collection was completed for Gainesville in August 2006. Species composition, height, diameter at breast height (DBH), and tree health was collected on 100-0.1 acre plots randomly placed within the city boundaries. From these data, the model is able to calculate leaf area, tree and leaf biomass, and species diversity. From these values, the hourly amount of pollution removed by the urban forest and the associated percent air quality improvement throughout a year will be estimated. Pollution removal will be calculated for ozone, sulfur dioxide, nitrogen dioxide, carbon monoxide, and particulate matter (<10 microns). In addition, hourly urban forest volatile organic compound emissions and the relative impact of tree species on net ozone and carbon monoxide formation throughout the year will be estimated. Total carbon stored and net carbon annually sequestered by the urban forest will be determined, as well as the effects of trees on building energy use and consequent effects on carbon dioxide emissions from power plants.

In collaboration with Dr. Francisco Escobedo, Assistant Professor at the University of Florida, we have initiated an analysis of urban forest soil quality characteristics. This work focuses on the soil quality found in Gainesville's urban forest and how these soils influence tree growth and hydrology. Both physical (soil strength, moisture, bulk density) and chemical (e.g., nutrient and heavy metals) analyses will be conducted on soils occurring in a variety of land uses. Studied land use types will include residential, commercial, industrial, transportation, institutional, agricultural, and forest. By linking above ground processes, such as tree growth, to below ground structure, such as soil texture and nutrient levels, specific management objectives can be developed to improve the function of urban forests.

Anticipated Results

From this study a dollar value of the forest and the value of air pollution removal and carbon storage and sequestration will be derived. Using the structural data, potential effect of southern pine bark beetle on tree health and management will be estimated and graphically illustrated.

Inventory methodology and other information about the model can be viewed at http://www.fs.fed.us/ne/syracuse/Tools/UFORE.htm.