Africa is the second largest continent after Asia with a total
area of 30.22 million km2 (including the adjacent islands).
It has great rivers such as the River Nile, which is the longest
in the world and flows a distance of 6650 km, and the River
Congo, which is the deepest in the world, as well as the second
largest in the world in terms of water availability. Yet,
Africa also has vast stretches of arid, semiarid, and desert
lands with little or no water. Further, Africa’s population is
projected to increase by four times by the year 2100, reaching
about four billion from the current population of little over
one billion. Food insecurity and malnutrition are already
highest in Africa (Heidhues et al., 2004) and the challenge
of meeting the food security needs of the fastest-growing
continent in the twenty-first century is daunting. So, many
solutions are thought of to ensure food security in Africa.
These ideas include such measures as increasing irrigation
in a continent that currently has just about 2% of the global
irrigated areas (Thenkabail et al., 2009a, 2010), improving
crop productivity (kg m−2), and increasing water productivity
(kg m−3). However, an overwhelming proportion of Africa’s
agriculture now takes place on uplands that have poor soil
fertility and water availability (Scholes, 1990). Thereby, the
interest in developing sustainable agriculture in Africa’s lowland
wetlands, considered by some as the “new frontier” in
agriculture, has swiftly increased in recent years. The lowland
wetland systems include the big wetland systems that
are prominent and widely recognized (Figure 9.1) as well as
the less prominent, but more widespread, inland valley (IV)
wetlands (Figures 9.2 through 9.8) that are all along the first
to highest order river systems..
