P3DM: Mapping for sustainable agriculture

Sanat K. Chakraborty

Sanat Chakraborty explains how participatory 3D modelling has helped an isolated Indian hill community to optimize their land use.

‘You can see our entire village right in front you’, the head of the village told the group sitting around the 3D model. ‘You can also see where we are going to jhum this year. It is very clear’, he added proudly.

Participatory 3D modelling (P3DM) was introduced to Sasatgre, a village in the West Garo Hills in North Eeastern India, as part of the IFAD supported North Eastern Region Community Resource Management (NERCRM) project in May 2003. P3DM integrates all aspects of the mapping process – participatory resource mapping, data collection and model building – as well as applications of the model for decision making, and for monitoring and evaluating changes in land use. The changes are recorded (using colour-coding) on the 3D model and are digitized to produce a new map, which is then returned to the community for analysis and further decisions.
P3DM is a continuous process that requires gradual the scaling up of activities, follow-up and training. In Sasatgre, it is mostly used for allocating farm plots. The villagers practise jhum, the traditional slash-and-burn subsistence farming. Every November, the village head gathers together all 51 families and allocates to each of them a fallow forest plot. They then clear the plot and slash and burn the existing vegetation to provide a bed of nourishing ashes for their crops.

Allocating jhum plots

With the 3D model – a simple visual representation of the village and its surroundings – the process of selecting and allocating jhum plots for the next season has became much easier and clearer for everyone. At the November 2003 meeting, the community was to allocate plots on an area that had been lying fallow since 1996. First, a plastic sheet was laid on the top of the 3D model, onto which they traced the boundary of the 1996 jhum site, which covered an area of about 141 hectares. They realized that for 2004 they would need only 41 ha, so they could leave the remaining 100 ha (almost two-thirds) lying fallow for at least another year. Rather than allowing families to clear a plot anywhere on the site, as before, the villagers decided to organize the allocation of the 51 jhum plots more systematically. By regulating access to the fallow land, they decided, they would be able to protect their water catchment areas, and create a community forest reserve. Sasatgre followed the same process in November 2004.

With the assistance of the NERCRMP, villagers have also used the 3D model to monitor government infrastructure building schemes. For example, when the Public Health Engineering Department announced a plan to build a water supply scheme that would run through the village, community leaders asked officials to indicate the route of the pipeline on the model so that they could assess how the project would affect them. The officials visited Sasatgre and used the model to discuss the plan.

Land use in Sasatgre was first digitized in May 2003. Since then, the villagers have recorded changes in land use in the last two cropping seasons by marking them on the model using coloured paints. However, these changes still need to be digitized to produce a map for long-term impact analysis. Digitization is very important for the process, as it helps the community to optimize the use of their jhum plots, thus allowing the land to lie fallow for as long as possible. Unfortunately, since the initial NERCRMP intervention in May 2003, there has been no proper facilitation or follow-up by either the project sponsors or trainers, presenting a major problem for the community.

Critical issues

The people of Sasatgre are still enthusiastic about the 3D model as a visual tool, and appreciate its benefits. Yet the experience has raised a number of critical issues. In particular, they cannot use P3DM to its full potential unless they have adequate expert support. How should they scale up the process? Who should drive the process, and whose purposes should it serve? Although many villagers are illiterate, they possess a wealth of information about their land and its resources. How can they best use this knowledge, with the aid of technology, for the benefit of the community? All changes in land use have to be digitized and stored for monitoring and impact analysis, but how can the community monitor these changes effectively without the right tools and training?

Under the NERCRMP initiative, several 3D models have been constructed in the region primarily to promote the tool and raise awareness of its potential. With appropriate support, a comprehensive jhum site and fallow land management system could be developed for upland areas throughout the region, where the communities themselves will be able to design and direct the process. The people of Sasatgre have learned that introducing technology is not enough.

Sanat K. Chakraborty ( gosanat@dte.vsnl.net.in ) is a journalist based in India. For more information about the North Eastern Region Community Resource Management (NERCRM) project, visit www.necorps.org . See also www.iapad.org/publications/ppgis/grassroots_options.pdf .


This project was first featured in ICT Update 27, September 2005


Different applications of P3DM:

IAPAD’s website provides an illustrated step-by-step description of a P3DM process as well as a list of resources, links and case studies.

Manual on Participatory 3-D Modeling for Natural Resource Management is a tool designed for practitioners who would like to plan and facilitate the preparation of 3-D models through a community-based process.

01 November 2005

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