IPCC Fourth Assessment Report: Climate Change 2007
Climate Change 2007: Working Group II: Impacts, Adaptation and Vulnerability Agriculture and forestry

Some adaptation measures aiming to reduce climate change impacts have been proposed in the agricultural sector. For example, in Ecuador, options such as agro-ecological zoning and appropriate sowing and harvesting seasons, the introduction of higher-yielding varieties, installation of irrigation systems, adequate use of fertilisers, and implementation of a system for controlling pests and disease were proposed (NC-Ecuador, 2000). In Guyana several adjustments relating to crop variety (thermal and moisture requirements and shorter-maturing varieties), soil management, land allocation to increase cultivable area, using new sources of water (recycling of wastewater), harvesting efficiency, and purchases to supplement production (fertilisers and machinery) were identified (NC-Guyana, 2002).

In other countries, adaptation measures have been assessed by means of crop simulation models. For example, in the Pampas region of Argentina, anticipating planting dates and the use of wheat and maize genotypes with longer growth cycles would take advantage of projected longer growing seasons as a result of the shortening of the period when frosts may occur (Magrin and Travasso, 2002). More recently, Travasso et al. (2006) reported that, in South Brazil, Uruguay and Argentina, the negative impacts of future climate on maize and soybean production could be offset by changing planting dates and adding supplementary irrigation.

In terms of food security, a significant number of smallholders and subsistence farmers may be particularly vulnerable to climate change in the short term, and their adaptation options may be more limited. Of particular concern are farmers in Central America, where drying trends have been reported, and in the poorer regions of the Andes. Adaptations in these communities may involve policies for market development of new and existing crop and livestock products, breeding drought-tolerant crops, modified farm-management practices, and improved infrastructure for off-farm employment generation. Increasingly, cross-sectoral perspectives are needed when considering adaptation options in these communities (Jones and Thornton, 2003; Eakin, 2005). In dry areas of north-eastern Brazil, where small farmers are among the social groups most vulnerable to climate change, the production of vegetable oils from native plants (e.g., castor bean) to supply the bio-diesel industry has been proposed as an adaptation measure (La Rovere et al., 2006).

A global study (which includes case studies of northern Argentina and south-eastern Brazil) concluded that in northern Argentina occasional problems in water supply for agriculture under the current climate may be exacerbated by climate change, and may require timely improvements in crop cultivars, irrigation and drainage technology, and water management. Conversely, in south-eastern Brazil, future water supply for agriculture is likely to be plentiful (Rosenzweig et al., 2004).

As a way of avoiding the consequences of deforestation as a likely impact on the regional climate, several measures are currently being initiated in the region and are likely to be intensified in the future. Argentina, Brazil, Costa Rica and Peru have adopted new forestry laws and policies that include better regulatory measures, sustainability principles, expansion of protected areas, certification of forestry products and expansion of forest plantations into non-forested areas (Tomaselli, 2001). In the Brazilian Amazon state of Mato Grosso, where 18,000 km2 of forest and savannas were converted to pasture and soybean fields in 2003, requirements for licensing of deforestation and environmental certification of soybean have been introduced as a way to preserve the environment. A similar proposal is under development for the Mato Grosso cattle industry (Nepstad, 2004). Most countries provide incentives for managing their native forests: exemption from land taxes (Chile, Ecuador), technical assistance (Ecuador), and subsidies (Argentina, Mexico and Colombia) (UNEP, 2003a). Chile and Guyana demand prior studies on environmental impact before approving forestry projects, depending upon their importance; Mexico, Belize, Costa Rica and Brazil are already applying forestry certification. Argentina, Chile, Paraguay, Costa Rica and Mexico have established model forests designed to demonstrate the application of sustainable management, taking into account productive and environmental aspects, and with the wide participation of civilian society, including community and indigenous groups.