Los pastores utilizan los mapas e imágenes por satélite para describir el uso del suelo en EtiopíaMassimiliano Rossi
Italo Rizzi Italo Rizzi
Un equipo de investigadores combinan mapas, imágenes satelitales y técnicas de cartografía participativa para desarrollar una imagen exacta del uso de la tierra entre los pastores del sur de Etiopía.
The amount of land given over to growing crops has dramatically increased in the last few decades, leading to a reduction of available grazing land in many places. Pastoralists are restricted to grazing their livestock in smaller pastures, which results in overgrazing and added pressure on the land. Inevitably, some plants and animals can no longer survive in these areas. And, as the species disappear, valuable knowledge of the local fauna and flora is also lost.
In an effort to better understand changing land patterns and preserve indigenous knowledge, researchers are using participatory mapping techniques. Spatial visualization tools, such as three-dimensional modelling, rural appraisal community maps, printed maps and even screen-based computer planning exercises with communities, can help to give an overview of natural available resources and how they are shared among the various land users.
These techniques are commonly used to improve land planning, promote communication, encourage debate and research, and develop environmental management strategies. In some cases, they have even solved boundary disputes between ethnic groups.
Although these community maps were often little more than lines drawn in the sand, or sketches on paper, they played a key role in giving communities the chance to express their needs and understand the delicate balances on which their livelihoods are based.
Drawing a sketch map to show the resources of an indigenous community became an important contact point between local knowledge systems and the scientific world. This is particularly important because traditional relationships with the environment have been so poorly understood and neglected in recent times. When working with pastoralists, for example, the outlines gave researchers a better understanding of local perceptions about the status and quality of pastures, rangelands, water sources, livestock types, the movement of people and their relative pressures on the local ecosystems.
But subjectivity and inconsistency in spatial representation, especially when considering a large area of land, meant that these maps were only of limited use when they were used outside the original village or read by non-pastoralists. The question, therefore, was how to translate symbols on a piece of paper in a way that could be understood by everyone. One solution was to involve the communities in the interpretation of high resolution satellite images.
The Lay Volunteer International Association (LVIA) tested this methodology for the first time in Moyale and Miyo woredas (districts) of southern Ethiopia at the beginning of April 2009. The project used the same idea as community maps, but substituted a piece of paper with geo-referenced maps and remotely-sensed imagery.
LVIA identified four woredas, spread over more than 2,300 sq km, and used 1:25,000 scale maps to carry out a series of participatory exercises with 15 different groups of pastoralists. In combination with high resolution satellite images, the community members were asked to identify a variety of features on the maps.
The team discovered that after only a few minutes of explanation, the pastoralists could consistently and accurately interpret features on the maps and satellite images. Women in particular showed a great ability and accuracy for locating features such as cultivated land and private enclosures. Men were more reliable in pointing out administrative boundaries, while the young livestock scouts could quickly recognize migration routes.
By combining the input of the different groups, the team was able to gather complete and accurate information on infrastructure, the locations of wet and dry grazing areas, livestock migration routes, water sources and administrative boundaries, as well as detailed information on the sharing of natural resources across multiple territorial units.
The team manually entered all the data they had collected into a GIS (geographic information system) program. They then produced a number of posters and maps which they took back to the communities to verify the details. Once collated, the final results will be used by local and central governments to support planning initiatives, to manage vulnerable water sources and, with a better understanding of the communities’ needs and land use patterns, to protect the livelihoods of pastoralists.
The study area still has a wide variety of animal and plant species. Because of this, the government has designated a large part of the study region as a protected area, and it could soon be established as a reserve. While the main focus of the research was to preserve indigenous knowledge and the pastoralists’ way of life, the results will also improve understanding of the needs of all land users and help to maintain a rich diversity of life.