Natural Rubber links global industry to millions of family farms. To ensure the sustainability of plantations, conditions should remain favourable during one or two decades. How can such conditions be ensured when the environment is changing? From farm-survey, ecological studies and experiments a multi-disciplinary methodology is developed in Thailand to identify significant indicators to assess the long-term adaptation and sustainability of smallholder’s plantation systems.

Risks and adaptations related to climate. The increase in global temperature will affect directly agriculture, particularly in the tropical area (IPCC 2007). Drought is the more likely climatic risk as rubber plantations expand towards drier areas, and due to the more irregular rain patterns. The hydraulic properties of rubber clones are considered a key for their adaptability to drought. It is also relevant to assess the effects of drought on soil biology, which maintains soil fertility. Extreme events, like flooding, are likely to increase as well but their actual occurrence and effects on rubber trees and farms is not well documented. As rainfall is becoming more erratic, farmers tend to adopt irregular tapping patterns. Assessing the resulting physiological status of trees will help identify adaptive strategies.

Changes in socio-economic context. Rubber price fluctuations have greatly affected the sector recently. This is a risk for farmer’s budget but also an incentive for flexible production systems. Plantations are extending towards new areas where their sustainability is questioned, whereas new investors get involved. These changes will affect the functioning of both the field-plant system and the production system. There is a need to identify the way socio-economic factors interact with biophysical factors to determine farmers’ strategies regarding risks induced by global changes.

Environmental issues. The impact of rubber plantations on natural resources and associated environmental services has been poorly studied. Environmental impacts affect the plantation in terms of soil sustainability (soil fertility preservation related to soil functional diversity) and generate externalities. We consider the risk linked to the extension of rubber plantations in sub-optimal regions and the risk of soil degradation in the traditional area of cultivation after 50 years of continuous rubber cropping.