Mapping social values to evaluate pressure on forest covered land

It can be argued that sustainable environment can be achieved only when pluralistic uses are appreciated and taken into account on the land. The physical features of the environment are rather straightforwardly measured and compiled to e.g. maps. On the other hand, the social environment is more complex to measure because it is built on perceived, subjective and qualitative data. In societal processes the meeting and control of these two is essential. For planning and constructing sustainable environments, it is though of primary importance that sound understanding of the environmental processes is combined with stakeholders’ participation. Only through participation is it possible to cater the real users of a particular area; those people who possess local knowledge. The latest development in the field of participatory planning is the use of Geographical Information Systems (GIS). These Participatory GIS (PGIS) methods combine participation with the use of digital geospatial techniques.

Through mapping of social values we are able to produce local social knowledge in spatial form. Every individual has important information about the perceived and experienced social environment. When this data is combined with the existing data of the physical environment it is possible to produce land use models in two dimensional space. These provide us with a synthetic view of land use. Neither data of the physical environment nor data of the social environment as such can depict the pluralism in the landscape. Both levels are of importance when environmental sustainability is considered.

In this case study participatory orthophoto mapping has been used to depict the use and values regarding natural resources in Zanzibar islands, Tanzania. Spatial data sets of the social environment were created through mapping five different social values in the village landscape in the administrative region of Matemwe. Form the study area, there is a data stock consisting of aerial images, topographic maps, statistic information and government documents describing the region. These have been used as a starting point to analyze the spatio-temporal land cover and land use dynamics. However, the results lack the social dimension of the land use. Based on the aerial images and map data it is not possible to obtain information about the perceptual environment and the actual use of the land by the local community. Hence, we may overlook some important aspects of the land cover and land use dynamics if we do not combine data of the social environment in the analysis.

The collected local spatial knowledge was analyzed together with the existing map and remotely sensed data in GIS to produce an integrated model of land use for the study area. This model indicates areas where forest covered land is most intensively used and sustainability of the forest resources under increasing pressure. The results also show those areas that are significant for the every day life and cultural traditions of the local community and have high preservation priority. The model is of use when tackling with the high population growth, intensifying shifting cultivation related to it and the expanding tourism industry in the study area and in general in Zanzibar islands. Integration of physical and social features in land use analyses can lead to better planning and management of natural resources.