Topographic Position Index (TPI) to identify floodable areas and zoning of plant species in a mangrove swamp in the South Pacific of Nicaragua

Abstract

COP7 recognized that mangroves are vulnerable ecosystems and threatened by habitat loss and degradation, which need urgent actions to guarantee their conservation and rational use. Geomorphological and hydrological processes are key to the growth and development of mangrove forests. However, in Central America, very few studies exist in this regard. Mangrove forests offer valuable economic and ecological services, such as tourism and shelter for species of flora and fauna. Furthermore, they protect against sea-level rise caused by climate change. The hydrology of the mangrove swamp of Río Ostional, in the South Pacific of Nicaragua, has been studied in recent years suggesting a relationship between mangrove species and freshwater inputs. In this project, the use of the Topographic Position Index (TPI) was explored to identify small-scale floodplains with little variation in elevation in a mangrove swamp. For this, a geomorphological characterization was carried out through a detailed topographic survey of the area and the analysis of the TPI as a method of classifying landforms to identify the flood zones; as well as the zoning of plant species. The classification of the TPI was related to the zoning of species. This relationship will allow the identification of the most sensitive areas to geomorphological modifications of possible anthropic origin, which is an essential input for comprehensive forest management.