Axis 3. of the Ecology Department /
Because we are numerous and strong, our needs are insatiable, we have a very strong imprint on the environment. Ecosystems in other areas of the DoE are trying to understand the operation is almost always a "human component" in close interaction with other ecosystem components (fauna, flora, soil, atmosphere ...). This is especially true in India where the population is very large. So we need to include this component in our research to better understand the processes at the border between ecological sciences and social sciences.
How to propose more sustainable managements of our environment? How to preserve living species while continuing to take part? How not to over reduce biodiversity of our ecosystems, without the freeze provided in protected areas inaccessible? How to continue to benefit from the services we provide our ecosystems without jeopardizing their survival? The project in this area of emerging DoE explores the conditions for sustainable management of biodiversity in landscapes of the Western Ghats and north-east India. These projects are based on detailed inventories of agroforestry landscapes and vegetation of these sites, as well as lifestyles of their players, to reconstruct the past workings and propose new management strategies combining biodiversity conservation and local development. They rely as much on recent methods of Environmental Sciences, Information Systems (GIS) and numerical models of landscape.
Figure 1: Modeling of a village in Coorg in the Ghats
An object on which human beings have an undeniable action is what we call the landscape. The landscape that we embrace the view from the top of a hill is an object on a human scale, bringing together the vegetation and landscape features (such as linear networks such as roads or rivers) that man constantly remodels for its needs. Certainly effective approach to address the above questions is to understand how these landscapes work, then try to use this acquired knowledge to predict (albeit with a relative accuracy) future behavior of these landscapes that we would have changed.
This is possible by numerical modeling. We developed the DoE modeling tools to simulate the dynamics of landscapes discontinuous (patchy called) as a result of human decisions or transitions between different types of natural vegetation. DYPAL is a landscape modeling platform, which has a friendly and intuitive software interface to simulate a wide variety of rural landscapes (agricultural, forest, suburban ...). Let us consider a specific case of Indian landscape, for which we would like to deepen our understanding of how it works:
choose for example the village of Kottoli, representative of agroforestry landscapes of Coorg (Western Ghats region, Fig. 3). What is the future of this landscape of coffee plantations in the hills and rice paddies in the lowlands? What are the sociological and anthropological conflicts that animate this landscape? What are its environmental issues and how to manage in the best interest of Man as well as its environment?
A detailed scientific study, based on the accumulated experience of DoE in the area during the course of the project CAFNET, addressed some of these issues. In the main questions we wanted to know what was the future of coffee plantations in the village of Kottoli planted in native species of trees and not in imported species (such as Silver Oak, Grevillea robusta). We also wanted to anticipate the dynamics of this village in the case of a crisis of coffee or a right to the trees allocated to farmers.
A set of interviews with owners and land users were first helped to capture the complex dynamics that are played within the village (Fig. 1), and achieve a typology of farmers present. Simulations involving agricultural decision rules (Fig. 2), and formalized from a formal grammar, then allowed simulating these dynamics with the modeling platform DYPAL landscape (Fig. 3). This model was calibrated and validated in several cases, so that it arrives well in reproducing the spatial and temporal characteristics of the area, such as gradients or changes in land use.
For all simulated scenarios, we observe a decrease in local species of trees and forests, gradually converted into coffee plantations with Silver Oak and cultures. Rice fields no longer develop as they have already been converted into fallow where possible. Most growers have recognized that a law on the trees (tree rights), would encourage them to keep their native forests, or at least to replant native species, but sessions "role play" make us doubt that they be held to this attitude in economic reality. Finally, tourism already present in the area could increase albeit fairly marginal.
Such estimates are preliminary, and are associated with large uncertainties. It would suffice that the price of coffee to ignite they lose their semblance of realism. But these scenarios are already yielding valuable information, and to verify some of our assumptions. For example, it seems predictable that soon native forests have nearly all disappeared from the area. Or, we predict a very low probability that tourism dominates one day village activities of Kottoli.