Discovering Africover approach

by Antonio Di Gregorio

This section of the site is designed to provide a deeper technical insight on the approach developed by Africover. These pages are part of the Africover methodological approach document which is currently in progress. This document will be available in the download section of the web site as soon as possible.

Africover developed an integrated system designed to provide to a broad user community the way to answer their environment related information needs.

The Africover approach brings together:

- the necessity to produce detailed, powerful and flexible land cover information
- the need to allow end users to extract the information they need
- the power of Remote Sensing and GIS technologies

This goal is achieved providing both the methodology, standards and tools to develop complex databases on environmental resources and the tools required by different users to interact with that complexity.

The continuity of information production and use is assured by the seamless integration of the two phases through consistent conceptual foundation and software modularity.

This section of the site will guide you through the various aspects of the Africover methodology:

- thematic classification: LCCS
- cartographic standards
- interpretative process: the software
- inside MADE
- aggregations
- interpretative process: the interpretation chain
- using the data: dedicated software

All this aspects are aimed at the production of the Multipurpose Africover Data-base for Environmental information (MADE).

Thematic interpretation : translating the reality in spatial information

Thematic interpretation is a process of information extraction: reality is generalized and captured in a spatial database. Because of this generalization the content/amount of the information stored in the database will be always a subset of the reality. Nevertheless the different degrees of efficiency of this extraction process are a basic key factor for the success of any cartographic work.

These are the main aspects influencing this process:

1. The thematic aspect (the classification/legend adopted)

An example of the generalization process linked with the thematic representation of reality is, for instance, the choice of a correct classification system. If the area to be mapped has 100 different land cover features and the classification system used only 50 classes there is a loss (generalization) of 50% of thematic information, only due to the thematic description of the reality.

2. The cartographic standards

An immediate example is the scale adopted for mapping. It is obvious that the smaller the final scale will be the bigger the cartographic generalization will be (This is more valid when a visual or a semi-automatic interpretation is used).

3. The interpretative process

It comprises a series of elements as: type, quality, date of remote sensing data utilized, knowledge of the study area, skill of the photo-interpreters, type of image processing software used, amount of field work done, the overall methodological interpretative approach used, etc. each of them strongly influencing the final result.

Africover methodology at global level

Standards and methodologies developed by Africover are at the base of an initiative for global land cover mapping jointly launched by FAO and UNEP (Global Land Cover Network) to answer the need for user customized standard land cover information at global level.

LCCS: FAO/UNEP international standard

LCCS has been adopted as international land cover classification standard system by FAO and UNEP.

Any identified land cover, anywhere in the world, can readily be accommodated. This internationally recognized system can consequently serve as a worldwide land cover reference basis.

Why Land cover ?

Land cover is the most important element needed for the description and the study of the environment; as the basic information for environmental databases, it is considered the only geographically explicit feature that can be used as a geographical reference by other disciplines.

The development of Africover methodology

The methodology, operational procedures and software tools for the land cover analysis in the Africover program have been developed by the Africover Eastern Africa module under the financing of the Italian Cooperation.