In effect, trading these concentrates means trading the environmental impact. Worldwide, trading feed grain and other feedstuffs involves a massive transfer of nutrients, depleting the production resources, and fertilizing, and often polluting, the location of final use. The production of concentrate feeds has an impact upon the natural resource base at various stages of crop production, trade and processing of feeds. Production affects land use through deforestation and change of habitats, and it has an impact upon biodiversity and aesthetic aspects of the landscape. In addition, there are direct effects of cropping on soils, water and air, and indirect effects as a result of the production and supply of inputs to agriculture such as machinery, fuels, fertilizers and pesticides.
Cereals are the major component of livestock concentrate feed.
Thirty-two percent of the world's cereal production is consumed by livestock. Yet this cereal is produced on only 20 percent of the total cereal cropland. The total of all cereals, oilseeds and roots and tubers used for livestock feeding is 744 million tons. Hendy et al ., 1995. Averages based on 1990 to 1992 data indicate that global cereal production was 1854 million tons, of which 600 million tons were used for livestock feed.