Caractérisation de la dynamique de l'occupation du sol en zone urbaine et périurbaine de Cap-Haïtien (Haïti)

Abstract

Cap-Haitian is the second largest city in the Republic of Haiti with nearly 5% of annual population growth. Cap-Haitian population growth causes built-up expansion and has a big impact on landscape and vegetation cover. This situation makes the city more vulnerable to natural disaster such as flooding. For this reason, this study characterized the land cover dynamics at the city-scale and along the urbanization gradient in order to evaluate its impact on ecosystems. Using three Landsat images from 1986, 2003 and 2017 supported by on-site verification (throughout April and May 2017), three land cover maps were generated. The landscape dynamic analysis was carried out through the use of two transition matrices of land cover areas, supported by landscape metrics analysis and the identification of spatial transformation processes. The results showed a strong and dynamic built-up expansion which led to doubling the built-up area during the last three decades, this has mainly affected agriculture lands. The woody vegetation surface has been halved in 31 years, in favor of crops but also to a lesser extent to new urban settlements. The creation of the new anthropogenic patches (buildings, crops), sustained by rapid population growth, led to the dissection of woody vegetation patches in the landscape. It has also been observed that the causes of landscape anthropization vary along the urbanization gradient. While in (sub) urban zones, urbanization causes crops’ and mangroves’ (woody vegetation) fragmentation, in rural areas; agricultural development leads to a significant woody vegetation degradation. Cap-Haitian city’s environment is changing rapidly, this encourages local authorities to implement a new sustainable urban development plan, in order to control anthropization, increase city’s resilience.