Resource information
Land degradation in the tropics is strongly associated with human population growth. The latter phenomenon is quite marked in humid areas and in the temperate highlands (Jahnke 1982). Notably in the plateaux of Sub-Saharan Africa and Asia, several pastoral systems have gradually evolved into mixed farming, in order to cope with such pressure (Ruthenberg, 1980). Land is more intensively utilized as population density increases since mixed systems are more efficient than specialized crop or livestock systems (McIntire et al.,1992). In fact, livestock crop integration allows:
to diversify production,
to distribute labour and harvest better throughout the year as well as distribute tasks among the different components of the household (HH),
to recycle waste products within the system, preventing nutrient losses,
to minimize the risk and the effects of livestock and crop pests;
to improve indigenous husbandry techniques and knowledge, hence
to intensify and control more efficiently input - output flows, increasing productivity and minimizing risks.
Livestock provide not only draught power, manure, milk, meat and by-products. As in traditional pastoral societies, they have cash buffer and insurance functions. The former function also supports the use of inputs in crop cultivation which in turn generates higher on-farm productivity for both crops and livestock (Brumby, 1986).
On the other hand, human population growth is responsible for decreasing land plot size. In Rwanda and Burundi, this pressure led to stocking rates much lower than in other East African highlands (50 TLU/km2 vs. 100–130 TLU/km2, according to the zone) due to increasing conversion of pasture into cultivated land (de Leeuw and Reid, 1995). In these areas, the doubling time of human population is around 20 years. In Sidama, Southern Ethiopia, a similar pattern was already described in 1975 by Ayele who stated that “cultivation has been and is invading livestock grazing areas. As population increases, people prefer to cultivate crops rather than breed livestock”.
The progressive disappearance of livestock is a key destabilizing factor responsible for the involution of the system characterized by nutrients deficiencies and degradation. It may lead to conflicts between different groups sharing resources within the system. This trend is more evident in the absence of marketing opportunities for livestock and/or crop products (Ruthenberg, 1980; Steinfeld et al., 1997).
In Sidama Awraja (or district) a WHO/UNICEF Joint Nutritional Support Programme (JNSP) was implemented during the second half of the 1980's. The area was selected because it presented a variety of environmental, socio-economic and cultural situations. This study, carried out as part of the programme activities, illustrates the role played by livestock in alleviating land degradation, poverty and the resulting child malnutrition in integrated systems.
