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erated erosion and the increase in the sediment load in rivers
and lakes (FAO, 1998).
Chemical contamination of the soil and water, which
also derives from the technologies of intensive agriculture,
has been increasing in the last 30 years. Nitrification of the
soil and water is directly related to the use of chemical fertilizers
(UNEP, 2006); in LAC the use of fertilizers increased
from less than one million tonnes in 1961 to more than 13
million tonnes in 2003 (FAOSTAT, 2005).
Water. In terms of water, the region has relatively favorable
endowments compared to other areas in the developing
world. It has almost half of the world’s total renewable
water resources and some 90% of the land area falls
in the humid or sub-humid zones. While overall the region
is relatively wet, there are several areas where drylands predominate,
principally in northern and central Mexico and
the coastal and inland valleys of Peru, Chile and Western
Argentina, Northeast Brazil and the Yucatan Peninsula and
the Gran Chaco area of Paraguay, Bolivia and Argentina.
In total, drylands comprise some 15% of the region (FAO,
1998). Natural grasslands or savannahs, many of which are
relatively dry, are found in much of Argentina, as well as in
central, western and southern Brazil, Uruguay and parts of
Colombia, Venezuela and Guyana. Crops occupy around
160 million ha of the region, while another 600 million
ha are dedicated to pasture and grazing land (Dixon et al.,
2001).
Hydrobiological resources represent another component
of South America’s biodiversity, with approximately
3,000 fish species. Nonetheless, very little is known of the
biological cycle of the fish species dependent on the water
cycle and even less of the zooplankton and phytoplankton
of the continental and marine waters (Bernal and Agudelo,
2006).
Agrobiodiversity. Mesoamerica and the Andes are two major
centers of origin of domesticated plants, many of which
are now of global importance. Maize and beans are the most
prominent of these, but the list also includes potatoes, sweet
potatoes, tomatoes, cassava, chili peppers, gourds, squashes,
avocado, cotton and peanuts. Wild ancestors have been
discovered for some of these crops, such as maize. There is
also significant genetic diversity across the region that has
been developed since the introduction of non-native crops
such as banana and sugar cane. With a few exceptions, the
region’s agrobiodiversity is not well studied.
Maize (Zea mays) is one of the most significant crops
that originated in the Americas; it is now the most widely
grown crop in the world. Due to its ability to grow under
highly varied climatic conditions, it is grown in at least 164
countries worldwide (Global Crop Diversity Trust, 2007).
Mexico is the center of origin and the center of diversity
for maize, with more than 60 landraces and numerous local
varieties, as well as the wild relatives of maize, the teosintes.
Mexico provides one of the earliest examples of deliberate
conservation of wild crop relatives in situ; the existence of
teosinte was the primary reason for the creation of the Sierra
de Manantlán Man and the Biosphere Reserve there in 1988
(Iltis, 1994; Meilleur and Hodgkin, 2004). |
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The common bean (Phaseolus vulgaris) appears to have
been domesticated separately in Mesoamerica and in the Andean
region. Wild gene pools are also concentrated in these
areas. Mesoamerican cultivars dominate global production;
some 60% of beans produced throughout the world are of
Mesoamerican origin. Common beans are the world’s most
important legume food crop and are particularly important
for human nutrition because of the high protein content,
which is roughly double that of most cereals (Beebe et al.,
2000).
Potato (Solanum tuberosum) was domesticated 7,000
years ago around Lake Titicaca in the Andes (Spooner et al.,
2005). Potato is the most important crop for the cultures in
the Andes, where over 100 varieties can be found growing
within a single valley (Brush, 1992).
Relatively few animals were domesticated in the new
world; only one, the turkey, has spread significantly beyond
its native habitats in Mesoamerica and the present-day
United States. The llama and alpaca, domesticated in the
Andes, still play an important role in Andean society, as
does the guinea pig, domesticated for food. The Muscovy
duck was also domesticated in South America. Wild relatives
of some of these animals, particularly the wild turkey
and the vicuña, which is related to llamas and alpacas, are
still to be found in the areas where they were domesticated
(Heiser, 1990).
The agricultural genetic resources of the Latin American
region are enormous. As one of only a few places where
agriculture was independently invented and the center of
origin of many of the world’s major food crops, the area retains
numerous landraces, local varieties and wild relatives
of great importance to the future development of agriculture
worldwide.
Economic resources. As a result of the structural adjustment
processes in the context of globalization, changes have
taken place in the agricultural sector in LAC that have had
a differential impact on the population in three ways: (1)
changes in incomes as there have been changes in wages,
employment levels and the prices of goods, especially essential
goods, such as food items; (2) changes in the levels
and composition of public spending, especially social spending;
and (3) changes in working conditions, such as type
of contracting, hours and social security. The changes have
included greater differentiation in the conditions of production
between small and large producers and there are fewer
agricultural jobs, with adverse results for many sectors due
to the increase in poverty and inequality in the rural world
(Da Silva, 2004).
Among the causes of the reduction in employment, Da
Silva (2004) cites increases in labor productivity, relative stability
of the agricultural frontier and the expansion of stockraising
and forestry, which do not require much labor. Other
categories that have been expanding (such as fruit crops,
vegetable crops and poultry) are using ever more contract
agriculture, which is based on more capital and also reduces
employment (Da Silva, 2004; Deere, 2005). According to
several sources compiled by David et al. (2001), approximately
66% of the poor who live in the rural sectors—47
million people—are small-scale producers, 30% are landless |