Environmental Engineering Reference
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problem. The Food and Agriculture Organization (FAO) of the United Nations estimates
that in the period of 2010 to 2012, approximately 870 million people, representing 12.5%
of the global population, were chronically undernourished. Of these 870 million, it is
estimated that about 850 million live in underdeveloped countries (FAO, WFP, and IFAD,
2012). The Rome Declaration on World Food Security called for a decrease of undernour-
ished people from the present amount to 400 million by the year 2015. If one factors in the
increase in population up until that time, this would mean a rate reduction of undernour-
ished people of more than 50% (WFS, 1996).
The demands for food are immense and as we have discussed previously in Chapter 1,
according to the Malthusian model, food availability is linked with population growth
(Malthus, 1798). It has been estimated (Daily et al., 1998) that by 2050, food demand
(a) could double in response to population growth, (b) would increase in relation to per
capita income, and (c) would increase in response to measures to reverse the undernutri-
tion of the poor. Increased urbanization has decreased available agricultural land. To
increase yields, the use of fertilizer and pest control chemicals has increased. Irrigated
areas have expanded and high-yield crops have been developed. Some of these agri-
cultural activities designed to enhance crop yields have led to decreases in soil fertility
and increases in soil and water contamination. Subsequent depletion of the soil resource
and the presence of these contaminants could lead to a decline in per capita food pro-
duction according to Meadows et al. (1992), which could be a threat to human survival
(Commoner, 1971). More than 75% of the arable land in North and Latin America, 25% in
Europe and 16% in Oceania can be considered damaged. This threatens future food sup-
plies (Fischer Taschenbuch, 1996). North America's breadbasket (the U.S. Midwest to the
Great Plains in Canada) is particularly at risk due to wind and soil erosion and fertility
loss. Loss of native habitat in Canada due to farming has been signiicant. The Canadian
Biodiversity Information Network (CBIN) reports that more than 85% of shortgrass prai-
rie, 80% of mixed-grass prairie, 85% of aspen parkland, and almost all the native tallgrass
prairie have been lost (CBIN, 1998).
Food production must be increased without increasing the impact on the geoenviron-
ment. Improper irrigation can lead to waterlogging and soil salinity problems. Use of pest
control chemicals has increased pest resistance and destroyed natural species (NRC, 1991).
The many aspects of agricultural engineering and soil management practices are subjects
that are well studied in soil science and agronomy. Their attention to eficient food and
crop production, together with research into the various issues of soil management and
soil quality have the aim of providing agricultural productivity without compromising the
objectives of sustainable agriculture.
6.1.2 Geoenvironment Engineering: Sustainable Issues
There are many stressor impact issues associated with agricultural-based production of food.
Most, if not all, of them are issues that fall under the purview of agricultural engineering
and soil science. That being said, there are some impact issues that are common to geoenviron-
mental engineering land management. These issues—i.e., the stressors and their impacts—
constitute the focus of this chapter. The discussion in this chapter is directed toward the
likely geoenvironmental impacts due to food production activities such as pesticide use,
nutrient addition, and waste management as depicted in Figure 6.1. The geoenvironment-
associated problems resulting from these activities are common to those found in land dis-
posal of wastes and other soil contamination problems encountered in geoenvironmental
engineering. Discussion on management, alleviation, and mitigation of the impacts due to
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