(Smil, 2000; Trewavas, 2002). By way of contrast, the critics of conventional/productivist agriculture argue that it is possible to attain levels of production equal to those of conventional agriculture and in some cases higher, using agroecological practices and without transgenics (Pretty, 2002; Halberg et al., 2005; Badgley et al., 2007).

     Based strictly on measures of yield (production per unit of area of a single crop), many economists and agronomists conclude that the conventional/productivist system has greater productivity. Nonetheless, many small-scale producers practice multicropping. Peter Rosset (1999), analyzing data from several countries, concluded that the small properties almost always produce more per unit of area than large ones. Indeed, "the inverse relationship between farm size and productivity," is widely accepted by agricultural economists, though there is a major debate over the causal mechanism (Yotopoulos and Lau, 1971; Bardhan, 1973; Sen, 1975; Berry and Cline, 1979; De Janvry, 1981; Carter, 1984; Feder, 1984; Assunção and Ghatak, 2003). The conventional/ productivist system is less energy efficient than the traditional/indigenous systems and in most cases than agroecological/ organic systems (Figure 1-12).

Agroecological system. This type of agriculture encompasses a wide array of systems, practices and methods that use agroecological principles to design and manage production systems. For the purpose of this evaluation we are including organic systems. Nonetheless, most agroecologists argue that organic systems are not necessarily agroecological. For example, the production of organic bananas in some parts of Central America and Ecuador, which consists of large expanses of monoculture and which are certified organic are not agroecological systems. Many small producers in LAC are adopting agroecological practices, but either because their production is not for the market or due to lack of resources to pay the certifying authorities, do not certify their production. In the last 20 years the agroecology movement has grown enormously worldwide and particularly in LAC. A recent study reports 286 projects with agroecological interventions that include 12.6 million producers on approximately 37 million ha, or the equivalent of 3% of the land in non-industrialized countries (Pretty et al., 2006). IFOAM estimates that almost 20% of all land and 28% of all farms with organic certification worldwide are in LAC (Willer and Jussefi, 2007) (Box 1-11), though this is largely due to extensive organic livestock systems, especially in Argentina, which has three million ha certified organic. Mexico is the country with the largest number of organic farms in the world, with more than 85,000 farms in organic management. It is estimated that in LAC there are some 5.8 million ha certified organic, with an annual value of US$100 million (Lernoud, 2007). Cuba is the only country in the world that is carrying out a massive conversion to organic agriculture, through the promotion of agroecological practices in both rural and urban areas (Box 1-12). In contrast to the other countries in LAC where organic production is for the export market, in Cuba organic production, with some exceptions, is not certified and is for domestic consumption.

     It is frequently stated that organic agriculture, because of its lower yields, will not be able to supply enough food to feed the world. To address this question a study from the

University of Michigan compiled results from almost 300 studies worldwide comparing yields of organic and conventional systems (Badgley et al., 2007). Based on the evidence the authors concluded that organic agriculture could produce enough food, on a per capita basis, to provide 2,640 to 4,380 kilocalories per person per day depending on the model used. They also found that in developing countries, where organic systems were compared to the commonly practiced agriculture, organic farms outperformed conventional practices by 57%, demonstrating that intensification using organic methods is possible.

     Another study, by the University of Essex in England, carried out a census of 286 projects in 57 countries, including 45 in Latin America and the Caribbean (Pretty et al., 2003, 2006). When the yields on farmland using agroeco-