From Historical Maps to Remote Sensing: Reconstructing Land Use Changes on Norfolk Island over the Past 250 Years

Abstract

ABSTRACT This paper aims to quantify land cover and vegetation changes over the past 250 years on Norfolk Island, Australia, a remote island important for its cultural heritage and biodiversity. We collated over 130 historical maps and aerial photos from various archives, of which we georeferenced 80. Supervised classification and manual digitization were used to extract detailed land cover information on vegetation cover from 10 historical maps and datasets. While the classification and symbology used to represent vegetation on the different maps varied over time, we were able to track changes in vegetation cover on the island. We found that after the first (colonial) settlement, non-agricultural vegetation cover was at its lowest during the 1940s, and has since then expanded. We found high constancy of land cover patterns on the island since 1840 onwards. Historical maps thus provide an understanding of the dynamics that shape the present landscape.