Effects of Earthquake and Human Migration on Land Cover Change and Mass Wasting from the 2010 Haiti Earthquake

Abstract:

Introduction

The 2010 earthquake in Haiti displaced millions of people and drastically induced mass wasting. The purpose of this study is to explore comprehensive relationships between population displacement and landslide frequency by comparing land use and land cover (LULC) maps of pre- and post-earthquake. To assess the impact of anthropogenic activities, we employed a maximum likelihood method to produce LULC maps from Landsat images for the dry season of 2000, 2002, 2005, 2008, 2010, 2012, and 2014. Landslide inventory maps were created with ArcGIS and Google Earth to visually detect mass wasting coverage for each year. We assessed LULC characteristics of new landslide areas for pre- and post-earthquake to find out what types of land cover most likely caused landslide events and how they were affected by anthropogenic activities in Haiti. The result (Figure 1) shows that the majority of the landslides occurred in the areas of bare soil and grassland over the entire period of this study. These types of land cover are generally considered to be landslide prone due to lack of forest, which leads to a weakening of slope stability. In the earthquake year of 2010, landslide events were dominantly found in bare soil (67.5%) while grassland only occupied 5.1% of total land use. After the earthquake, landslides increased 14.6% in the forest areas, and then decreased to 7% of the total land use in 2014. Post-earthquake data shows an increase of urban area landslides (16%). After the earthquake from 2010 to 2012, landslides in the forest area noticeably increased. This may be due to refugee camps, which were constructed after the earthquake. Clearing trees for biomass energy might have resulted in poor slope stability because roots are necessary to maintain soils.