Agriculture Reference
In-Depth Information
Figure
9.16.
World soil moisture regimes where: Aridic is dry more than half the year. Ustic is
between Aridic and Udic. Xeric in winter is cool and wet and in summer is warm and dry. Udic is
not dry for more than 90 days. Perudic is always wet. Interfrost is frozen at some depth most of
the year. Permafrost soil is frozen at some depth all the time. (Courtesy of U.S. Department of
Agriculture, Natural Resources Conservation Service, Soil Survey Division, World Soil Resources,
Washington, D.C. (http:
//
soils.usda.gov
/
use
/
worldsoils.mapindex
/
.)
Niger and Water
The agriculture problem in Niger is the lack of water because the country lies on
the edge of the Sahara Desert. Therefore, planting on the contour, contour fur-
rowing, and increasing the organic matter in the A horizon will all result in slow-
ing or preventing rain runoff as well as increasing infiltration and the
water-holding capacity of the soil. Mulching and minimum tillage will also result
in water conservation and an increase in the available water for crop production
and thus food availability. Irrigation is not an option in many areas as there is no
source of water for irrigation.
9.11.1 Water Sources
Water for agriculture comes from three main sources: rain, bodies of water (including
streams, rivers, ponds, and lakes), and wells. These sources are not equal in quantity
nor quality. Natural rain when available in sufficient quantity is the best source of
water for crops. Worldwide well water is most frequently used for human and
animal consumption. Bodies of water are used for both irrigation and drinking water
for humans and animals.
