Throughout Europe, farmland represents the major
land use; in Britain for example, 77% of the land area
(18.5 million ha) was under agricultural production in
2001 (DEFRA, 2002). As a consequence, a high proportion
of Europes biodiversity now exists on land dedicated
to the production of food, where every effort is
made to make as great a proportion of primary production
as possible available for human consumption
(Krebs et al., 1999). Such intensity of production has resulted
in the biological simplification of the farmed environment
and the creation of semi-artificial ecosystems
that require constant human intervention to regulate
their internal function (Altieri, 1999).