Globally, floodplains have experienced floods of different magnitudes at different times.
As such the inundations of floodplains affect agricultural activities and such impact is
evident. In Namibia, the Zambezi Region has experienced high variability in rainfall
patterns, extreme rainfall and flood in space (spatial) and time (temporal) more than any
other region as a result of climate variability. The non-flooded landscape units
consequently become the only available option for crop farming activities during
flooded years. The agronomic productivity status of these non-flooded landscape units
in terms of soil and climatic factors as well as their land suitability for maize production
in space and time given the prevailing climatic conditions has not been investigated. At
the same time our understanding of how small-scale farmers in the region incorporate
soil and climate factors into their crop production decisions is limited and affects the
provision of extension advice. Yet soil and climatic factors clearly influence land use
activities, including rain-fed maize production. The overall objective using maize as a
case study crop was to assess possible ways that might optimize the non-flooded
landscape units to support arable production in the Zambezi Region. The study was
undertaken at both local and regional level using the Kwalala non-flooded landscape
unit in the Kabbe North Constituency. Thus, the soil moisture and temperature were
measured at various soil depths (20, 40 and 60 cm) between October 2012 and October
2015 using the Decagon data collection system (data loggers and sensors). In addition,
secondary climatic and soil data were collected. Hence, Multiple Regression Analysis
ii
(model) and the CropWat model (K4 research model) as quantitative methods were used
for data analysis. Findings in this study suggests that the observed soil moisture content
varied from 9.7 to 33 VWC % loamy sand soils; 7.9 to 26.1 VWC % sandy loamy soils;
and 4.9 to 22.9 VWC % sandy soils during the growing period between October and
April. At the same time the maize crop water requirements (CWR) and maize water use
(ETo) observed for the area ranged from 1.25 to 5.79 mm/day (CWR) and 4.01 to 4.44
mm/day (ETo). Therefore water content sufficiency was significantly (p< 0.05)
available to sustain the agronomic crops during the growing period between October and
April. Thus these findings implies that the non-flooded landscape units are suitable for
rainfed maize production in the context of rainfall, soil type, soil depth, soil temperature,
and soil water content sufficiency as well as maize CWR and ETo as long as November
is the planting date or 130 days growing period. The incorporation of these findings
may mitigate the effects of land conversion by guiding such transformation in an
ecologically appropriate direction to ensure sustainable agronomic production, for
example, if such non-flooded landscape units are aimed to be used for maize production
purposes. It is therefore recommended that further studies on soil moisture induced by
the flood be carried out to provide an insight on the soil moisture content driven to top
soil surface by flood, since during the period of this study extreme flood did not take
place and led to question one of this study not been answered