Objectifs scientifiques et projet de recherche

Land use is changing rapidly in Thailand and LaoPDR: a fast expansion of commercial tree plantations is observed, particularly rubber tree (Hevea brasiliensis) plantations, due to the increasing demand for natural latex on the international market. Despite the economic importance of rubber tree plantations in South-East Asia (SEA), their social and environmental impacts are still poorly studied.
In LaoPDR there is a transition from conservation forest to rubber tree whereas in Northeast Thailand the transition is from annual cash crops to rubber tree.
To determine whether rubber plantations induce environmental degradations or improvements, the scientific objective of this project is to specify the impact of these land use changes (forest or crop transition) on soil functions related to ecosystems services as well as socio agronomic issues.
This project on the environmental consequences of rubber tree plantations (LUC) will be organized around four work packages:
1 - socio-economic consequences
2 - soil functional diversity
3 - nutrient cycling , and
4 - carbon sequestration
The measurements will be undertaken in rubber tree plantations of different ages (chronosequence) or with different management practices.
To study these complex and interrelated aspects, our project associatesThai and Lao lecturers and researchers with complementary skills: socio-agronomist, agricultural system specialists, tree physiologists, agronomists, soil ecologists, soil physicists and soil microbiologists.The goal is to strengthen the capacity of this team, in order to study the environmental impacts of any other land use change in the future.Moreover, the skills of this team will be useful beyond the borders of the two involved countries because ecology and particularly soil ecology is still poorly taught in SEA.
To add an ecological flavour to agronomical sciences is particularly relevant in SEA, which undergoes constant land use changes du to economical constraints.
IRD’s support will help providing a theoretical and practical background in soil ecology and in recent analytical techniques.
Beside scientific publications, one of the main capacity building outcomes of this project will be
1 - the reinforcement of Lao scientific community via the supervision of Lao PhD and masters students
2 - the building up of a regional (Lao-Thai) young expert research team able to address future environmental management challenges in SEA
One of the expected key academic outcomes will include the development of a master module on soil functional ecology (with common curriculum at KKU and NUOL); a practical outcome will be the tentative design of practices for the sustainable management of rubber tree plantations and associated soil resources.

Unités IRD

4R24200 : IEES-Paris

4R21000 : ECO&SOLS

Partenaires / Unités de recherche associés

KKU : Khon Kaen university

Responsable

M. Kiriya SUNGTHONGWISES

Correspondants

M. Christian HARTMANN

M. Alain BRAUMAN

Disciplines scientifiques

Sciences de la Terre, univers, espace

Thématique(s)

The project will start with a survey of farmers’ practices and soil characteristics in order to choose
1 - One chronosequence to study the long term impact of rubber tree on soil functioning
2 - A set of fields based on the surveys of agricultural practices where the environmental impact of these practices will be assess In parallel, an experimental agronomic layout will be set up in order to better address the impact of agricultural practices such as intercropping on soil and tree functioning.