Expanding the agriculture and livestock boundaries

Irrigated area (1 000 hectares): Latin America and the Caribbean

The irrigated area in Latin America and the Caribbean has expanded at an average of nearly 2 per cent a year over the period 1972-99 Source: FAOSTAT 2001

Agricultural expansion has intensified the use of natural resources and exacerbated many of the processes of land degradation. Over the past three decades, there has been an increase in arable land and grassland at the expense of forests. During 1972-99, the area of permanent arable land and cropland expanded in South America by 30.2 million ha or 35.1 per cent, in Meso-America by 6.3 million ha or 21.3 per cent and in the Caribbean by 1.8 million ha or 32.0 per cent (FAOSTAT 2001). The area under irrigation (see graph) also increased in the same period, resulting in greater agricultural production throughout the region. The expansion of permanent arable land on soils previously covered by forests is still the main cause of deforestation in the Brazilian Amazon (Nepstad and others 1999). Soybean production, mostly for export, has been the main driving force to expand the agricultural boundary in northern Argentina, eastern Paraguay and the central part of Brazil (Klink, Macedo and Mueller 1994).

The expansion of livestock production has also been a major driving force behind land conversion in the region. The process could not have been successful without the strong support of governments through the provision of tax incentives (the 'Legal Amazon' in Brazil), the construction of roads and the availability of skilled and cheap labour. For example, livestock companies in Bolivia leased land to peasants so that they could clear it for cultivation and then return it already cleared when their leases expired (Giglo 2000). Erosion, loss of nutrients, chemical pollution, salinization and the effects of meteorological and geological phenomena are major contributors to the different land degradation processes.