Technical Note: Inter‐annual analysis of deforestation hotspots in Madagascar from high temporal resolution satellite observations

Abstract

The island of Madagascar is one of the world's highest conservation priorities due to its unique species and ecosystems, which are reportedly threatened by rapid deforestation. Although designated a global ‘biodiversity hotspot’, there have been conflicting reports on the nature of the island's forest decline to date. Differences in forest estimates have resulted from the limited temporal scales of previous studies, non‐standardized definitions of forest and the incongruences of satellite data between different investigations. The aim of this study was to identify ‘hotspots’ of vegetation change within Madagascar to assist national biodiversity conservation planning. We used the Normalized Difference Vegetation Index derived from 14 consecutive years of satellite data from the National Oceanic and Atmospheric Administration's Advanced Very High Resolution Radiometer, to identify areas within the island's evergreen forests, which have undergone statistically significant vegetation change, either loss or gain, throughout the study period. Our results show that vegetation cover within the island's forest areas is highly dynamic, with vegetation loss and gain occurring throughout the study period. Most changes were located in the northern part of the island and in the central portion of the western boundary of the eastern evergreen forest belt. Designated protected areas did not safeguard against change events.

Acknowledgments

We would like to thank Robert Whittaker for his support and comments on the early stages of this research and the UK Government Darwin Initiative (project number 62/9/006) for sponsoring this work. We would also like to thank Marc Steininger and the team at Conservation International for providing us with the high spatial resolution map of deforestation. The authors would also like to thank two anonymous referees whose comments on an earlier draft have been very helpful. Correspondence and requests for materials to Jane Carter Ingram (e‐mail: jane.ingram@linacre‐oxford.com).