General
Scope
Ecological
and economic sustainability of land use on a savanna landscape in northern
Namibia
Savannas are the most common type of vegetation in the tropics and the subtropics. Some of the savannas of the African continent have been productive rangelands for thousands of years. Nowadays they are the home for large parts of the African population. At the same time, these ecosystems are increasingly endangered by environmentally mal-adapted human land use.
Considering the enormous economic significance of this ecosystem, it is astonishing how little we know about its ecological connections. Until recently savannas were understood to be systems in which one or several stages of stable equilibrium occurred. However, lately some authors postulate that savannas, on the level of several criteria, are event-driven systems in which certain disturbances play an important role in maintaining a savanna-like vegetation structure. The dynamic processes in savannas under pastoral land use are particularly complex. A fundamental understanding of these multiple interactions is indispensable for identifying or developing adequate forms of land management.
The dynamic processes in savanna rangelands are extremely complex, though. It is impossible to identify or even develop a successful land management without a fundamental understanding of these processes. Such an understanding can most probably be achieved through an interdisciplinary approach. For this, range ecology will be connected with analyses of the value systems and the economical profitability of such land management.
Therefore,
our research project “Range management and sustainability - Ecological and
economic sustainability of land use on a savanna landscape in northern
Namibia” has an integrative research design. Its scientific roots
lie in the collaborative research centre ACACIA at the University of
Cologne.
The project concentrates on an evaluation of the pasture management:
- “Which pasture system the most successful one from an ethnological and economic point of view (in the sense of profitably, risk minimization, and social acceptance)?”
- “Which
pasture system is ecologically the most successful one (in the
sense of the protection
of natural resources and maintaining productivity)?”
We will compare four different pasture systems in north-western Namibia that lay within a spatially narrow-limited area:
- Pastoral nomadism (Namibia’s Kaokoland under traditional use by the Himba people);
- Communal conservancy (communal land use of the Herero in nationally promoted game protectorates)
- Cattle farm (conservatively run cattle farms)
- Game farm (former cattle farms, now
run with game)
Similar sets of methods will be applied to all grazing systems so that results can be directly compared. We monitor vegetation traits on permanent plots that we set up along land use gradients (i. e. leading away from water places or settlements). In order to estimate the regeneration potential of the vegetation, we set up grazing exclosures. Studies on the demography, the household economy and social networks serve for the investigation of the socio-economical sustainability criteria. We interview shepherds and farmers on their knowledge of food types, their perception of current and former degradation, and their conceptualisation of degradation.
The results of our project will reveal causal relationships within the grazing systems under investigation and thus generate an understanding of processes, which is indispensable for the development of adequate management practices.