the role of tourism in natural resource management in the okavango ...

destination area's 'physical carrying capacity' for tourism activity. Hence, calls in the
tourism literature for environmental conservation are echoed in the World
Commission's belief that sustainable development does not endanger or degrade
the natural systems that support life on Earth. In the words of the World
Commission:
'Different limits hold for the use of energy, materials, water and land. Many of
these will manifest themselves in the form of rising costs and diminishing returns,
rather than in the form of any sudden loss of a resource base. The accumulation
of knowledge and the development of technology can enhance the carrying
capacity of the resource base. But ultimate limits there are, and sustainability
requires that long before these are reached, the world must ensure equitable
access to the constrained resource and reorient technological efforts to relieve the
pressure' (WCED, 1987, p.45).
The notion of limiting development to within environmental carrying capacities
applies to the several types of resources. Therefore, renewable resources, such as
animal and plant species used for food, clothing, building, fuel, medicines, etc., need
not be depleted for future generations provided that the rate of use does not exceed
the limits of natural regeneration and renewal, and this is the concept of 'sustainable
yield'. As previously discussed, tourism-related activities, such as collection and
killing for the souvenir trade, exceeded the sustainable yield for individual species
and since species interact, the reduction in numbers of one species through human
exploitation may have ecosystem-wide impacts, and the maximum sustainable yield
must also take account of these potential system-wide effects (Hunter and Green,
1995).
With regard to non-renewable resources such as fossil fuels, metallic and non­
metallic minerals, the World Commission upholds the view that sustainable
development requires that the rate of depletion of these resources should foreclose
as few future options as possible. Essentially, a non-renewable resource should not
be exhausted before acceptable substitutes or alternatives have been provided.
Emphasis should, therefore, focus on economy of use, re-use and recycling. Lastly,
the World Commission argues that the Earth's systems which support life,
(atmosphere, oceans, fresh-waters, soils, rock formations) are too often regarded as
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