540
cucumber and cabbage for manual irrigation using groundwater and surface water,
respectively. Cabbage is the most dominant crop in terms of acreage, and it is common with people who use manual pump for irrigation with surface water. The lifting
devices commonly in use are buckets and manually operated pumps such as treadle
pumps and concrete pedal pumps.
It is apparent that the types of crops grown differ across water controls. Farmers
in rain-fed agriculture cultivate seasonal crops such as maize, beans, cassava, sorghum and cotton; green maize and tomato, on the other hand, are dominant crops
with gravity flow irrigators as the market demand of green maize and tomatoes
justifies the extra investment costs. Horticultural crops such as cabbage, tomatoes
and onions are the dominant ones in motor and manual pump irrigators. This is so
because horticultural crops have a good return on investment. For this reason, watermelon and cabbage are observed to be more dominant in motor pump irrigation.
Overall, the results show that there is limited use of groundwater and gravity flow
for irrigation in both study sites, Mara and Iringa. This can be attributed to the fact
that the required capital investment for making wells or drilling boreholes is high.
Kashaigili (2010) noted that there are limited uses of groundwater for irrigation in
Tanzania due to several factors, including the fact that the majority of people in the
community have inadequate information and understanding of groundwater
resources. This has also been echoed by Mato (2002), Sadiki (2009) and Kongola
(2008), who recommend further research before groundwater can be put to largescale use for irrigation or other uses.
3.6 Financial Returns to Irrigation Under Different Water
Control Technologies
Table 7 presents the financial returns under different water control technologies in
the study area. The total income per household derived from the sale of crops under
rain-fed farming, WC1, is US$1,011.2 while for canal irrigation, WC2, is
US$1,447.1; under manual pump irrigation from surface water, WC3a, it is
US$970.3, under manual pump irrigation from groundwater, WC3b, it is US$703.6,
under motor pump irrigation from surface water, WC4a, it is US$1,609.9 and under
motor pump irrigation from groundwater, WC4b, it is US$436.9. The results show
that the total income from the sale of crops under motor pump irrigation from surface water is higher than that for other water control technologies. Nevertheless, the
value added per family under surface and groundwater manual irrigation is comparatively higher, unlike that for other categories.
The study has revealed the existence of local markets for the agricultural crops
for both small and large scale. In Mara, horticultural crops have all-round market in
the village, especially during market days in the villages. The vegetable and fruits
are sold to hotels and lodges in Serengeti district. The owners of hotels and lodges
purchase the produce in bulk and pay farmers promptly. This has a direct benefit to
farmers. Vegetables and fruits from Iringa are sold in the local markets in Iringa, but
most of the supplies of vegetables and fruits (e.g. tomatoes, onions, cabbages, pepJ. J. Kashaigili
cucumber and cabbage for manual irrigation using groundwater and surface water,
respectively. Cabbage is the most dominant crop in terms of acreage, and it is common with people who use manual pump for irrigation with surface water. The lifting
devices commonly in use are buckets and manually operated pumps such as treadle
pumps and concrete pedal pumps.
It is apparent that the types of crops grown differ across water controls. Farmers
in rain-fed agriculture cultivate seasonal crops such as maize, beans, cassava, sorghum and cotton; green maize and tomato, on the other hand, are dominant crops
with gravity flow irrigators as the market demand of green maize and tomatoes
justifies the extra investment costs. Horticultural crops such as cabbage, tomatoes
and onions are the dominant ones in motor and manual pump irrigators. This is so
because horticultural crops have a good return on investment. For this reason, watermelon and cabbage are observed to be more dominant in motor pump irrigation.
Overall, the results show that there is limited use of groundwater and gravity flow
for irrigation in both study sites, Mara and Iringa. This can be attributed to the fact
that the required capital investment for making wells or drilling boreholes is high.
Kashaigili (2010) noted that there are limited uses of groundwater for irrigation in
Tanzania due to several factors, including the fact that the majority of people in the
community have inadequate information and understanding of groundwater
resources. This has also been echoed by Mato (2002), Sadiki (2009) and Kongola
(2008), who recommend further research before groundwater can be put to largescale use for irrigation or other uses.
3.6 Financial Returns to Irrigation Under Different Water
Control Technologies
Table 7 presents the financial returns under different water control technologies in
the study area. The total income per household derived from the sale of crops under
rain-fed farming, WC1, is US$1,011.2 while for canal irrigation, WC2, is
US$1,447.1; under manual pump irrigation from surface water, WC3a, it is
US$970.3, under manual pump irrigation from groundwater, WC3b, it is US$703.6,
under motor pump irrigation from surface water, WC4a, it is US$1,609.9 and under
motor pump irrigation from groundwater, WC4b, it is US$436.9. The results show
that the total income from the sale of crops under motor pump irrigation from surface water is higher than that for other water control technologies. Nevertheless, the
value added per family under surface and groundwater manual irrigation is comparatively higher, unlike that for other categories.
The study has revealed the existence of local markets for the agricultural crops
for both small and large scale. In Mara, horticultural crops have all-round market in
the village, especially during market days in the villages. The vegetable and fruits
are sold to hotels and lodges in Serengeti district. The owners of hotels and lodges
purchase the produce in bulk and pay farmers promptly. This has a direct benefit to
farmers. Vegetables and fruits from Iringa are sold in the local markets in Iringa, but
most of the supplies of vegetables and fruits (e.g. tomatoes, onions, cabbages, pepJ. J. Kashaigili