Landsat-based monitoring of landscape dynamics at Apostle Islands National Lakeshore: 1990–2018
Kirschbaum AA. 2022. Landsat-based monitoring of landscape dynamics at Apostle Islands National Lakeshore: 1990–2018. Natural Resource Data Series. NPS/GLKN/NRDS—2022/1346. National Park Service. Fort Collins, Colorado. https://doi.org/10.36967/nrds-2292920
Landscape disturbances such as forest harvest, blowdowns, fire, and development activities create patches on the landscape that modify the structure and function of ecosystems and watersheds. Understanding the timing, location, size, and intensity of these disturbances can assist resource managers in making decisions regarding management options. To provide information regarding these metrics, the Great Lakes Inventory and Monitoring Network implemented a long-term monitoring project to quantify landscape dynamics inside and surrounding Apostle Islands National Lakeshore using an automated satellite-based change detection program called LandTrendr (Landsat-based detection of trends in disturbance and recovery). This is the second report for Apostle Islands NL and varies slightly from the original report published in 2012 in terms of analysis area and the time period analyzed. The analysis area outside the park was expanded by including the entire Sand River, Fish Creek, White River, and Bad River watersheds. The time period analyzed has also increased by 23 years, from 2004–2009 (6 years) to 1990–2018 (29 years). Results of this updated analysis showed that disturbances inside the park due to forest pathogen defoliation affected the largest amount of land (91.31 ha), followed by blowdown (43.21 ha), with beaver and development being the only remaining disturbances detected inside the park (12.98 ha and 3.08 ha, respectively). Lands adjacent to the park in Bayfield, Ashland, and Iron counties, experienced far greater levels of disturbance, with forest pathogen (defoliation) accounting for half of the land disturbed outside the park (48,059 ha, or 1,657 ha per year). The second most prevalent disturbance agent outside the park was forest harvest, with 45,934 ha disturbed (average 1,583 ha per year) during the 29-year analysis period. Long-term monitoring of this analysis area will contribute to our understanding of how these disturbances may affect water quality of Lake Superior, spawning habitat in tributaries, and wildlife movement to the islands.
- Type
- Published Report
- Authors
- Kirschbaum, Alan
- Date of Issue
- 2022-03
- Publisher
- National Park Service
- DOI
- 10.36967/nrds-2292920
- Units
- APIS , GLKN , NRSS
- Keywords
- Apostle Islands, GLKN, Lake Superior, Land Use Monitor, Wisconsin