Skógræktarritið - 15.05.2001, Side 105

ment decision-making. But there
are still two main limitations to
most current DSTs: (1) firstly,
most are not yet spatially explicit.
i.e. they do not incorporate infor-
mation at the landscape scale on
the impacts of vegetation pattern
and topography on ranging
behaviour, partly because of a
lack of data and partly because
the software and computing
power have only recently become
sufficiently sophisticated; (2) sec-
ondly, most of the available graz-
ing models in the UK and else-
where deal either only with open-
ground vegetation or only with
forest, because as yet we still
have a poor understanding of for-
est use when it represents only a
small component of a whole
complex of vegetation types. For
this reason, a scoping studyis
currently being undertaken to see
where the main data shortages
are, before we embark on new
DST development for complex
landscapes containing patches of
forest within a ránge of other veg-
etation types. This would aid
managers of areas where trees
form only a minor part of the
landscape but where tree regen-
eration is a major aim.
Conclusion
Grazing management for forest
regeneration is a fundamentally
important, yet highly complex,
issue in countries such as
Scotland, where natural forests
have declined to such small
remaining areas. Development of
appropriate and sustainable
management recommendations
requires an integrated approach
to a subject which encompasses
many fields of expertise, from
plant and animal physiology and
ecology, through landscape sci-
ence, to economics. it is only by
integrating such approaches that
we will be able to move towards
the provision of sound prescrip-
tions for a range of herbivore/for-
est regeneration options within a
changing economic and political
climate.
Acknowledgements
I am grateful to Throstur
Eysteinsson for inviting me to
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