46
Water and energy are often considered as inputs to food system models reflecting
the demands that food production makes on water and energy and subject to possible supply constraints. Examples of how food systems place demands on water have
already been given. Examples of how food systems place demands on energy
include:
• Energy embedded “virtually” in the life cycle of agricultural inputs such as fertilizers, pesticides, and irrigation water.
• Energy demand (fuels) for operating agriculture equipment, transportation, and
distribution, and (electricity and natural gas) for the processing and preservation
of food products.
• Energy demand for agricultural labor.
Food systems are extremely nutrient-intensive because of the need for Nitrogen
(N) and Phosphorous (P) fertilizers on crops and because of the transportation of
nutrients and carbon embodied within food products. N and P limitations may
become critical for some food systems in the twenty-first century. N and P helped
create the “Green Revolution” in food production, but they are not unlimited
resources (especially P), and they contribute dramatically to freshwater pollution
via “nonpoint source” pollution of waterways and “dead zones” where oxygen has
been depleted from waters by oxygen-eating microorganisms feeding on N and P, so
fish cannot live.
In studies of food systems, the use of food crops as feedstocks for biofuels brings
competing demands for water with food production for human consumption. In the
USA, a large fraction of corn is used for ethanol production; Brazil is also a leader
in biofuel production from corn and sugar cane. Biofuel production is controversial
because “first generation” biofuels like corn ethanol compete with human food for
land and water resources. This is in contrast to “second generation” advanced
biofuels- based crops like algae, willow, switchgrass, and other woody products. See
Sect. 8.2.2 for more on biofuels.
Changes in land use and ecosystem functioning because of water- and energyrelated uses of land (e.g., mining, reservoirs, wind farms, pipelines, solar farms)
may or may not raise food production issues. The addition of solar and wind production has allowed landowners to “produce” renewable energy as a crop and maintain their other crop productions as well. At the same time, dams on rivers provide
both hydroelectric generation and supplies of water for agriculture.
Major considerations for modern food systems include the following:
• Concerns over genetic modification, pesticides and herbicides, and industrialscale food systems.
• Local food movements and farmer-to-consumer linkages.
• Organic food movements.
• Food cultures that emphasize authenticity or specific diets.
• Food self-sufficiency as national policy, with its consequences for water demand
in dry regions.
• The right to food as a local and national policy.
P. Saundry and B. L. Ruddell
Water and energy are often considered as inputs to food system models reflecting
the demands that food production makes on water and energy and subject to possible supply constraints. Examples of how food systems place demands on water have
already been given. Examples of how food systems place demands on energy
include:
• Energy embedded “virtually” in the life cycle of agricultural inputs such as fertilizers, pesticides, and irrigation water.
• Energy demand (fuels) for operating agriculture equipment, transportation, and
distribution, and (electricity and natural gas) for the processing and preservation
of food products.
• Energy demand for agricultural labor.
Food systems are extremely nutrient-intensive because of the need for Nitrogen
(N) and Phosphorous (P) fertilizers on crops and because of the transportation of
nutrients and carbon embodied within food products. N and P limitations may
become critical for some food systems in the twenty-first century. N and P helped
create the “Green Revolution” in food production, but they are not unlimited
resources (especially P), and they contribute dramatically to freshwater pollution
via “nonpoint source” pollution of waterways and “dead zones” where oxygen has
been depleted from waters by oxygen-eating microorganisms feeding on N and P, so
fish cannot live.
In studies of food systems, the use of food crops as feedstocks for biofuels brings
competing demands for water with food production for human consumption. In the
USA, a large fraction of corn is used for ethanol production; Brazil is also a leader
in biofuel production from corn and sugar cane. Biofuel production is controversial
because “first generation” biofuels like corn ethanol compete with human food for
land and water resources. This is in contrast to “second generation” advanced
biofuels- based crops like algae, willow, switchgrass, and other woody products. See
Sect. 8.2.2 for more on biofuels.
Changes in land use and ecosystem functioning because of water- and energyrelated uses of land (e.g., mining, reservoirs, wind farms, pipelines, solar farms)
may or may not raise food production issues. The addition of solar and wind production has allowed landowners to “produce” renewable energy as a crop and maintain their other crop productions as well. At the same time, dams on rivers provide
both hydroelectric generation and supplies of water for agriculture.
Major considerations for modern food systems include the following:
• Concerns over genetic modification, pesticides and herbicides, and industrialscale food systems.
• Local food movements and farmer-to-consumer linkages.
• Organic food movements.
• Food cultures that emphasize authenticity or specific diets.
• Food self-sufficiency as national policy, with its consequences for water demand
in dry regions.
• The right to food as a local and national policy.
P. Saundry and B. L. Ruddell