High-resolution multispectral satellite image and a postfire ground survey reveal prefire beetle damage on snags in Southern Alaska

Abstract

Alaskan spruce forests are exposed to both fire and spruce beetles [Dendroctonus rufipennis (Kirby)]. To understand the influence of spruce beetles on the process through which fire affects ecosystem function, we developed a reconstruction technique to measure prefire damage to trees caused by the spruce beetle. We validated our evaluation of prefire tree conditions using a high-resolution multispectral satellite image by comparing our results with a postfire ground survey. The prefire tree conditions determined by the two methods coincided well with each other. This result suggests that combining high-resolution multispectral imaging and postfire ground surveys of spruce beetles on snags is a powerful tool to determine the prefire condition of a forest in a changing boreal forest ecosystem.

Keywords:

• Climate change
• remote sensing
• black carbon
• combination of disturbances

Acknowledgments

We thank Mr B. Oskolkoff (Ninilchik Native Associations, Inc.) and Mr D. Buesseler for kindly allowing us to conduct this research in their properties. We deeply thank Prof. M. Fukuda and Prof. L. Hinzman for their support for this project. We also acknowledge Prof. T. Koike for his valuable comments. This project was funded by the project to utilize JAXA-IARC Information System (2007–2010) and a JSPS doctoral fellowship to Makoto, K. (No. 192105).