Environmental Engineering Reference
In-Depth Information
Protected areas, eviction and encroachment, game theory as an analytical
tool for assessing the viability of policy options
A central policy in Tanzania has been the creation of protected areas as
part of a broader strategy aiming to promote biodiversity conservation
and the meeting of local and national development needs. The viability of
these policies cannot be isolated from strategic interactions and decisions
made by dif erent individuals and institutions at the local level. As will
be illustrated in this section, game theory can also be useful in assessing
the viability and desirability of policy options in the context of strategic
interactions.
Until now, we have considered games made under the assumption that
players are symmetric, facing the same decision alternatives and being
in the same position, for example, both players being appropriators and
facing cooperate or defect strategies. These symmetries, however, can be
relaxed to construct games in which the strategies do not need to be the
same, nor the players to be assigned to the same positions.
Let us i rst try to map a decision problem faced by communities who are
living adjacent to a reserve and who are completely prevented from the use
of resources within the reserve.
Consider i rst a hypothetical scenario illustrated by Figure 10.11,
where M.1 represents the i rst node for a member or members of the
reserve adjacent communities and Ch.1 represents a chance decision
node with a probability distribution equal to 1. M.1 has two available
strategies: to trespass (t) and use the resources within the area or not to
trespass (~t). If the user trespasses and is not detected (~D) he or she
will receive a benei t (
B
) from the additional resources within the reserve
(for example, grazing land, water, wood, bushmeat, medical plants, and
so on) with a probability of (1 − a).
B
will be shaped by the availability,
quality and dependence of resources inside the reserve relative to those
D (
)
-
F
t
Ch.1
B
~D (1 -
)
M.1
~t
Figure 10.11
The trespassing game
