Grasslands of the World.pdf - Disasters and Conflicts - UNEP

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Grasslands of the world
recently, molecular techniques using RAPD markers were applied to study the
genetic diversity in the same collection, and also among farm clones in Kenya
(Lowe et al., 2003). This technique was able to separate out hybrids between
P. purpureum and P. glaucum from pure elephant grass accessions. Despite being
clonally propagated, genetic diversity (Magguran, 1988) across all accessions
was found to be fairly high, with a Shannon’s diversity index of 0.306.
Panicum maximum is another tall, fast growing species that is often found
associated with Pennisetum in eastern Africa n grasslands or associated with
Cenchrus and Bothriochloa in Acacia woodland in the dry savannah areas
(Rattray, 1960). Herlocker (1999) recognized the Panicum-Hyparrhenia region
along the coast northwards from Tanzania , through Kenya into Somalia .
Panicum maximum is more widely distributed in Kenya, Ethiopia and Tanzania
and is typical of shady places in the foothills of mountain ranges up to 2 000 m.
P. maximum is a pioneer grass that comes in after clearing and cultivation of
the lowland forest . There is a wide variation in plant habit, robustness of culms
and pubescence (Phillips, 1995), and ecotypes with good agronomic characters
have been selected as commercial cultivars. P. maximum is fast growing and
palatable, and its wide adaptation and variability make it an excellent grazing
species in the savannahs. A collection of 426 ecotypes of P. maximum collected
from Tanzania and Kenya were evaluated for morphological and agronomic
traits in Brazil (Jank et al., 1997). Twenty-one morphological descriptors were
found to discriminate among accessions and were used to cluster the collection.
Considerable variation was found among the ecotypes and some with
wide adaptation were selected for establishment of a breeding programme.
Other locally well -adapted ecotypes are also being developed for use within
the region of adaptation.
POLITICAL AND SOCIAL SYSTEMS IN PASTORAL LANDS OF EASTERN
AFRICA
Most dry grasslands of eastern Africa are characterized by frequent droughts
and high levels of risk of production for pastoral peoples (Little, [2000]).
Livestock are one of the few ways to convert sunlight into nutritious food in
these drylands (wildlife are also important). Pastoralists traditionally manage
risk by moving their livestock on a daily and seasonal basis to follow changes in
the quality and quantity of pasture (IFAD, 1995). Cattle , camels , sheep , goats
and donkeys are the main livestock species and are kept by the pastoralists for
subsistence for their milk , meat and traction. Most herds are mixed as a means
of adaptation to a changing environment, to supply food for the family and to
act as a cash reserve in times of shortage, during droughts or disease-pandemics
(Niamir, 1991).
Although sale of livestock is a major source of income for pastoralists today,
widespread sale (or commoditization) of livestock only became common in the
last century, with colonialism (Hodgson, 2000). Settled crop-livestock farmers