Title: Methods for Mapping Forest Disturbance and Degradation from Optical Earth Observation Data: a Review,
Abstract: Purpose of review: This paper presents a review of the current state of the
art in remote sensing based monitoring of forest disturbances and forest
degradation from optical Earth Observation data. Part one comprises an overview
of currently available optical remote sensing sensors, which can be used for
forest disturbance and degradation mapping. Part two reviews the two main
categories of existing approaches: classical image-to-image change detection
and time series analysis. Recent findings: With the launch of the Sentinel-2a
satellite and available Landsat imagery, time series analysis has become the
most promising but also most demanding category of degradation mapping
approaches. Four time series classification methods are distinguished. The
methods are explained and their benefits and drawbacks are discussed. A
separate chapter presents a number of recent forest degradation mapping studies
for two different ecosystems: temperate forests with a geographical focus on
Europe and tropical forests with a geographical focus on Africa. Summary: The
review revealed that a wide variety of methods for the detection of forest
degradation is already available. Today, the main challenge is to transfer
these approaches to high resolution time series data from multiple sensors.
Future research should also focus on the classification of disturbance types
and the development of robust up-scalable methods to enable near real time
disturbance mapping in support of operational reactive measures.