mededelingen der zittingen bulletin des seances - Royal Academy ...

Suitability
class
Table 24
N um ber of food portions of 2,220 Kcal produced per km 2 under intensive farming
in the South Kivu test area
Cultivable
surface area
(ha)
Farm
size
(ha)
Number
of farms
Daily energetic
value of the
farm
(Kcalories)
Daily energetic
value of the
suitability class
(Kcalories)
Number of
food portions
of 2,220 Kcal
S l,l 12.67 1 12.6 22,142 278,989 125.7
S I,2 31.00 1 31.0 21,097 654,007 294.6
S2 5.92 1 5.9 16,551 97,650 44.0
Total/ mean 49.59 1 49.5 20,821 1,030,646 464.3
4. Conclusions
The test areas represent the western part of the Kivu mountain range where
recent developments of the population pressure have increased the demands
on agricultural resources. The currently applied traditional farming systems
do not allow a yield increase nor a sustainable intensification of the land
use. Unless more intensive agricultural systems are introduced, an increasing
population pressure will force farmers to cultivate steep lands and shorten
the fallow period, which will finally result in degradation of the land. The
introduction of intensive farming should consider adequate fertilizer application,
production of cash crops and the installation of anti-erosion measures.
Three of the four test areas, Butembo, Lubero and South Kivu, with soils
mainly developed on the sedimentary and metamorphic substrata of the Urundi
and Ruzizi systems, have a similar population supporting capacity (table 25).
Under traditional farming conditions our assessment suggests a population
supporting capacity of about 170 inhabitants per km2, consisting of a farmers’
population of 130 to 140 persons which, in addition to their own subsistence,
may produce the required food for 40 to 50 non-farming people. Under
intensive farming, these areas may supply food for 528 to 594 inhabitants
per km2 with a farmers’ population of 270 to 350 which may produce food
for 220 to 300 non-farming people.
The collectivities of the Lubero zone reported 24 to 83 inhabitants per km2
in 1984. The population of Butembo (73,312 in 1984) has reached at present
nearly 100,000 people, equivalent to about 78,000 adults. Assuming the availability
of 25.4 commercializable portions per km2, a saturated neighbouring
rural area of more than 3,000 km2, corresponding to a region with a radius
of above 30 km surrounding Butembo, is required for the food supply. This
suggests the intensification of agriculture around Butembo. The population
of Lubero, 13,343 in 1984, has grown to approximately 17,000 at present.