Environmental Engineering Reference
In-Depth Information
11. Economic valuation of dif erent forms
of land-use in semi-arid Tanzania
Deborah Kirby
Introduction
In many ecosystems there is a conl ict of interest between land-users who
wish to utilize the land for dif erent purposes. In most of these situations,
the overriding factor inl uencing the use of the land is its perceived economic
value. A forest or savanna region may produce many dif erent types of goods
for human use. Although these goods have a value to humankind, many
have traditionally been excluded from estimates of valuation. This has arisen
because policy-makers have generally assumed that natural ecosystems such
as forests or savannas have no economic value other than their direct use of
producing saleable products, and thus non-monetary values from their land-
use have been excluded from any economic analysis. Thus, forested areas
have only been valued in terms of timber production or land area available
for farming (Barreto et al., 1998), and savanna areas for the volume of sale-
able livestock (for example, Bembridge and Steenkamp, 1976).
A comparison of the relative values of the dif erent forms of land-use,
which includes all values of the resource, monetary and non-monetary,
can help identify a socially equitable use of land. This chapter considers
how valuations of dif erent forms of land-use can be made and emphasizes
the importance of establishing linkages between ecological and economic
systems to facilitate valuation of biological goods and services in a devel-
oping country, Tanzania. In this context, the use of a particular tool in
economic analysis, the production function, is described.
The importance of valuation of ecosystems
Many resources provided by ecosystems do not have a direct market
value. For example, the indirect values of ecosystem services provided
under traditional pastoral systems of land-use are harder to quantify com-
pared with the direct market prices of commercial ranching. Consequently,
evaluation of the economic worth of one system of land-use against
another will not be equitable if only those products that have a direct
market value are compared. One of the principal pressures on natural eco-
systems is their conversion into more productive systems in commercial
terms (Wilson, 1994). This occurs when decisions over land-use are taken
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