Agriculture Reference
In-Depth Information
were within acceptable short-term levels, except for lead and volatile or-
ganic compounds in some areas (Pardue et al., 2005).
18.5.1 CONTAMINATION OF WATERS
Higher water temperatures, increased precipitation intensity, and longer
periods of low flows exacerbate many forms of water pollution, including
sediments, nutrients, dissolved organic carbon, pathogens, pesticides and
salts (Kundzewicz, et al., 2007). In regions where intense rainfall is ex-
pected to increase, pollutants (pesticides, fertilizers, organic matter, heavy
metals, etc.) will be increasingly washed from soils to water bodies (Boor-
man, 2003). Higher runoff is expected to mobilizefertilizers and pesticides
to water bodies in regions where their application time and low vegetation
growth coincide with an increase in runoff (Soil and Water Conservation
Society, 2003). Because of compaction, heavy rainfall after drought can
result in more severe runoff and increased risk of certain types of contami-
nation. Alternating periods of floods and drought can therefore aggravate
the problem. Increasing ocean temperatures may indirectly influence hu-
man exposure to environmental contaminants in some foods (e.g., fish
and mammal fats). Ocean warming facilitates methylation of mercury and
subsequent uptake of methyl mercury in fish and mammals has been found
to increase by 3-5% for each 1ºC rise in water temperature. Temperature
increases in the North Atlantic are projected to increase rates of mercury
methylation in fish and marine mammals, thus increasing human dietary
exposure (Booth and Zeller, 2005).
Sea level rise related to climate change is expected to lead to saltwater
intrusion into aquifers/water tables in coastal areas. This will extend areas
of salinization of groundwater and estuaries, resulting in a decrease in
freshwater availability for humans, agriculture and ecosystems in coastal
areas. One-quarter of the global population lives in coastal regions; these
are water-scarce <10% of the global renewable water supply (WHO, 2005)
and are undergoing rapid population growth.
18.5.2 THE EFFECT OF CLIMATIC CHANGE ON THE COLD-
CHAIN
The food manufacturing industry utilizes chilling and freezing processes
as a means of preserving foods. Refrigeration of these foods is continued
