Helen Hambly and I had an interesting discussion this morning on the possibilities of using Ushahidi or a similar platform to support a participatory GIS initiative for sustainable agriculture. Among other things, maps can provide data on what she referred to as 'proxy indicators' related to natural resources and households. She explained to me how in parts of Africa is it possible to infer household income levels from satellite images of rooftops. For example, rooftops made of tin versus those of organic materials can be an indicator of household income.
Proxy indicators are just one possibility. Communities might use open GIS platforms to support a variety of knowledge sharing activities around crops, land use, livestock, etc. The important thing is to help the community to understand the value of such data and to provide means by which community members can do it themselves. These means are partly technical but also require awareness building and training.
One of the areas that may be worth exploring for our study is how a social practices approach to knowledge mobilization might help identify possibilities for participatory GIS practices.
Another area to explore is the range of options available to support participatory GIS practices. Ushahidi is a valuable platform but surely there are other possibilities that might be equally or better suited to agricultural communities of practice.
Here's a primer on participatory GIS from Rambaldi, et al.: http://www.iapad.org/participatory_gis.htm