Monitoring and evaluating the ecological integrity of forest ecosystems

www.frontiersinecology.org © The Ecological Society of America A managers, scientists, and policy makers increasingly recognize the value of ecological monitoring (Lovett et al. 2007), new monitoring programs are being implemented, and existing programs are undergoing redesign and improvement (Busch and Trexler 2003). Current investment in careful planning and design of monitoring programs will result in high-quality data for years to come. How can scientists and natural resource managers identify the most useful data to collect, and how can they effectively convey critical information – describing ecosystem condition – to policy makers and the public? Common challenges encountered in developing a monitoring program include identifying specific monitoring objectives, deciding what data to collect, and effectively interpreting and communicating the results (Noon 2003). Monitoring objectives are driven by management goals and will vary considerably among programs. For example, specific objectives for monitoring a forest managed for timber production may focus on tree regeneration and productivity, whereas those for monitoring a forest preserve may focus instead on maintenance of “natural” condition or preservation of wildlife habitat. Once objectives have been established, careful consideration should be given to the selection of specific variables to accomplish those objectives. Because it is impossible to monitor all the variables of interest, some criteria or process must be used to identify those that will provide the most useful information relative to the cost of measurement. Finally, a monitoring program will only fulfill its function if results are interpreted and reported in a way that is meaningful to a broad audience. Scientific reporting is important, but may reach only a fraction of those that need the information. The concept of “ecological integrity” provides a useful framework for selecting monitoring variables and assessing progress toward ecologically based management goals (Harwell et al. 1999). As part of the National Park Service’s (NPS) Vital Signs Monitoring Program (http:// science.nature.nps.gov/im/monitor/), we developed a protocol for monitoring the ecological integrity of temperate zone, forested ecosystems of the northeastern US. This protocol was developed specifically for the small, forested parks that make up the NPS Northeast Temperate Network (NETN), including Acadia National Park and a group of smaller (30to 1400-ha) national historical parks and sites REVIEWS REVIEWS REVIEWS