Agriculture Reference
In-Depth Information
can also cause lodging and leave the ground so wet that equipment cannot be used to
harvest the crop. Generally, hand harvesting before grain deterioration is also pre-
cluded, although if the ground freezes, it may become hard enough to allow for
mechanical harvesting.
Hail is an important consideration in some locations because it occurs during the
growing and fruiting season of crops. It can be extremely destructive both to edible and
nonedible portions of crop plants including grains, vegetables, and fruits. In some
locations, such as the northern highlands of Kenya farmers often plant beans under
corm. The theory is that the maize stalks and leaves will protect the beans during
hail storms.
In Sections 8.4.3 and 8.5 we discussed the adverse effects of both excess and
deficient precipitation. These, of course, also represent adverse weather conditions.
8.11 CLIMATE CHANGE AND POSSIBLE EFFECTS ON
FOOD PRODUCTION
Four aspects of climate change can have a predictable effect on food production:
increasing carbon dioxide in the air, increasing temperature, changes in rainfall, and
increasing winds. The first two changes should have a positive effect on crop pro-
duction. The third could be neutral or negative, particularly in relationship to animal
production. The last will have variable negative, neutral, and positive effects.
Changes in storm and rainfall patterns will dramatically affect crop production,
however, predicting the locality, number, and intensity of storms is not possible.
Carbon is an essential nutrient for all plants and is obtained from the atmosphere in
the form of carbon dioxide. Thus, increasing carbon dioxide concentrations in the
atmosphere are expected to lead to increases in plant growth, productivity, and yield
and thus food availability. To a certain extent increased plant productivity tends to
balance or counteract the increase of carbon dioxide in air.
Increases in temperature would lead to an increase in the land available for crop
production. Northern Hemisphere land, which is presently too cold or the growing
season too short because of low temperatures, would be available for farming. There
are large areas in North America and northern Russia that would become productive
by increased temperatures. Thus, one can make the argument that increasing world
temperatures would increase food availability.
To a certain extent this would be offset by loss of land along the oceans and other
bodies of water as their levels rise from melting polar ice. Flooding of these lowland
areas would provide high-quality fish sanctuaries and thus an increase in fish pro-
ductivity that could also be exploited to increase food production. Thus, this loss of
farmland would be, at least partially, offset by increased fish production.
Changes in rainfall can dramatically change agriculture and agricultural pro-
ductivity. Increases in rain can provide water needed for crop production and
could potentially allow crop production or increased crop production in areas
where there is little crop production today. On the other hand decreases in rainfall
will decrease agricultural productivity and can have long-range effects even out of
