EFFECTS OF GEOSPATIAL DATA SOURCES ON THE IDENTIFICATION AND CHARACTERIZATION OF BURNT AREAS IN PORTUGAL

C C Fonte,J Patriarca,D Duarte

doi:10.5194/isprs-annals-v-4-2021-49-2021

Abstract

Abstract. The work presented in this paper compares the burnt areas in continental Portugal in 2017 and 2018 mapped by three initiatives, namely the Portuguese Institute of Nature and Forests Conservation (ICNF), the Corine Land Cover (CLC) inventory of the Copernicus programme and the European Forest Fire Information System (EFFIS). Then, the Land Use Land Cover (LULC) classes affected by the 2017 burnt areas mapped by ICNF are analysed considering CLC 2018 and the 2018 LULC map produced by the Portuguese National Mapping Agency (Direção Geral do Território) – “Carta de Ocupação do Solo” (COS 2018). To enable a comparison between the classes of both LULC products, a nomenclature was selected and both CLC 2018 and COS 2018 were mapped into the chosen classes. The comparison of the burnt area’s extent showed that there are large differences in both area and levels of detail between the analysed data sources. The results regarding the LULC classes affected by the 2017 fires mapped by ICNF show large differences in terms of burnt area in each class as well as the proportion of the burnt areas associated to the classes. This analysis shows that very different results may be reached if different products are used, and therefore a large level of uncertainty is associated with the conclusions achieved with these products.

Highlights

Fire is considered to be one of the main factors regarding forest change globally, and one of the main drivers of desertification (Vieira et al, 2015)
The European Forest Fire Information System (EFFIS), which is a modular system consisting of web-based modules, data processing and spatial databases that process and store forest fire information regarding most of the European countries (SanMiguel-Ayanz et al, 2012), maps burnt areas globally generating a burnt area map every 10 days for the whole globe
To assess the Land Use Land Cover (LULC) classes that were affected by the burnt areas when using Corine Land Cover (CLC) 2018 and COS 2018, and be able to compare the results obtained with both data sets, it was necessary to define a nomenclature that could be mapped to classes of both products

Summary

Introduction

Fire is considered to be one of the main factors regarding forest change globally (van der Werf et al, 2006), and one of the main drivers of desertification (Vieira et al, 2015). The identification and characterization of burnt areas within a given time interval and location is central for several tasks, such as the accounting of greenhouse emissions (Prosperi et al, 2020), local, regional and international reporting frameworks which may guide future policy (Bowman et al, 2017) and its impact on, for example, soil quality (Kutiel and Inbar, 1993). Both national and international institutions aim at identifying the burnt areas of a given region to be used as input in these tasks. The mapping of such areas, namely using remote sensing techniques, is still a research topic where several researchers have proposed different mapping methodologies (Grégoire et al, 2003; Simon, 2004; Verhegghen et al, 2016)

Objectives

Methods

Results

Conclusion