Geographic Information Science: Monitoring, Mapping, Modeling, and Decision Making for the Great Green Wall Initiative

Abstract

Geographic Information Science (GIScience or GISci) — using the synergy of global positioning systems (GPS), remote sensing, spatial analysis and statistics, and geographic information systems (GIS) — provides a powerful set of tools and intellectual approaches to address environmental change. Since the advent of satellite remote sensing of Earth resources in the 1970s, new and innovative ways have been developed to map, measure, monitor, model, and provide decision support for the ongoing changes on our planetary surface. Healthy green vegetation has a unique spectral reflectance response due to absorption in the visible red portion of the spectrum and strong reflectance in the near infrared. Indexes derived from combinations of satellite digital data have been documented to provide good indicators of the amount and geographic coverage of green vegetation. Thus, GIScience methods can be very helpful in spatial reasoning and scientific visualization of the success of agroforestry programs designed to combat desertification. Change detection or monitoring of the success of establishing green vegetation can be accomplished in a geographic information system using multiple dates of satellite imagery or aerial photography. In addition, when information about the state of the vegetation cover is combined with other digital data types, such as soils, access to water, transportation routes, the location of human settlements, and/or natural vegetation cover, then strategic decisions regarding development of the Great Green Wall can be made.