Keynote Presentation: Food, Water, and Energy

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The Last Food Mile Conference
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Other Food Science
Water Resource Management
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Giegengack, Robert

While blatant food waste late in the production chain is apparent to most of us, less apparent is the inefficiency of resource use in the processes whereby we produce, harvest, process, package, store, and deliver the food that we eat. We waste water: 72% of water “used” worldwide is applied directly to cropland, much of it via archaic technology. We move water from where it is plentiful to places where we imagine it will be more useful. We waste nutrients, even those that we know are in limited supply, by careless or excessive application. Effluent from fertilized cropland has contaminated soils, groundwater, streams, and vast areas of the ocean. We waste our wild fisheries by extraction beyond their capacity to recover, and by contaminating the water on which they depend. Exhaustion of marine fisheries was extensive before the first inventories were undertaken; thus, available baselines of fishery declines are not adequate to inform current management strategies. We waste energy by pumping irrigation water against gravity, and in every stage of the food industry. Today, the US food industry invests 10 calories of energy for every food calorie delivered to an American household. Surviving subsistence-agriculture societies deliver as much as 50 food calories for every calorie invested. Most of those invested calories today come from fossil hydrocarbons. We have largely eliminated natural ecosystems, replacing floral diversity with industrialized monoculture, and wild fauna with food animals, Fifty percent of the crops that we raise we use to feed food animals, which we then eat. We have not exploited opportunities to develop alternative food sources via hydroponic systems, aquaculture, insectivory, nutrient recycling, etc. In 1900 the Earth supported 1.6 billion people, many of them not well. Futurists of that time estimated that the carrying capacity of Earth was not higher than 2.5 billion people. Today we feed 7.2 billion people more calories/person than was the case in 1900, higher in the food chain, and on less land than was under cultivation in 1900. This has been achieved via development of a synthetic fertilizer industry, by selection of high-yielding crops, by energy-intensive cultivation practices, and, most recently, by genetic manipulation of food plants and animals. We have not extended the global carrying capacity by reverting to traditional agricultural practices. Even with these advances, we do not feed 7.2 billion people well. However, nutrition deficiencies are more the consequence of distribution inefficiencies than of inadequate supply. The systems that now produce food for 7.2 billion people can accommodate many more, as even newer technical advances are developed and implemented. But the most obvious and immediate strategy to feed the people we now have, and the people we expect, is to reform current practices to reduce waste in every stage of the food industry. The global food industry has come a long way. Rational analysis and judicious inventiveness can substantially advance the capacity of that industry to accommodate a larger human population.

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