Landscapes Forest and Global Change - ESA - Escola Superior ...

V. Caboun 2010. New classification and utilization of forest functions in landscape
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Forest management as a production sector lives on the sale of own products. From this
viewpoint production forest functions brings profit and all other forest functions are
only a load for forest manager, it means they are not equal to production function. The
core of the integration of forest functions is namely mutual comparison and evaluation
of various forest functions, their reflection in the system of management in forest and
assessment of benefits resulting from various ways and interlinking of forest functions
use into optimal proportions. Forest manager must know which forest benefits the
society needs to be able to set the goals of management.
Our task was not simple as it is to construct the classification system of the assessment of the
potential of forest functions and real fulfilment of the functions by forest growing in various site
conditions and types of the landscape with various utilization and degree of anthropic changes
with regard to real state of forest, its current tree species composition, age and spatial structure,
ecological stability considering not only historical development and present state but also
expected global and regional (mainly climatic) changes and anthropogenic effects as well as
with regard to social requirements and interests of the owners.
2.2 Analysis of ecological-stabilization and functional effectiveness of forest
ecosystems in the landscape
On the basis of available literature experimental results there was carried out primary analysis of
the functional effectiveness of forest ecosystems in the landscape and the system for its
detection and classification was worked out. This system follows up the system of the
classification of ecological stability (Caboun 2002, 2003), as long-term ecological stability is a
basic precondition for securing long-term functionality of forests.
We understand ecological stability as an ability of the ecosystem to resist or compensate
external as well as internal effects without any marked permanent disturbing of the functional
structure of this system.
Natural ecosystem develops in accordance with given conditions and usual abiotic and biotic
factors. These conditions and factors form ecosystem (the effect of the environment) what
appears also for the given conditions in its specific structure (tree species composition, age and
spatial structure) and subsequently in its ecological stability. Optimal solution from the
viewpoint of ecological stability, and thus also optimal functionality of the ecosystem is on the
basis of our knowledge solution of nature through natural ecosystems. A man from the
viewpoint of the need of satisfying own needs influenced the structure of forests to different
extent, and thus he influenced also their ecological balance, ecological stability and
subsequently resulting fulfilment of the forest functions.
Graphs of percent reduction of partial ecological stability in dependence on the degree of
difference of the studied indicator of a real (assessed) forest ecosystem in comparison with
optimal forest ecosystem corresponding to the site are a part of the classification system of
partial ecological stability of individual indicators. Construction of models or their specification
to the level of forest types or types of forest is a demanding and long-term task of further
research in cooperation with the people who implemented and verified the proposed system.
The determination of the ecological stability for individual time horizons is based on individual
development phases or their changes during the studied period as well as presupposed site
changes during this time.
For each development phase it is possible to determine in general the range of its primary –
initial ecological stability on the basis of hypothetical models of ecological stability and its
components of individual development phases of tree species.
The sense and practical importance of ecological stability lies in the fact that on the basis of
found facts and values it is possible to propose and optimal way of management in accordance
with natural regularities in a way to strengthen the required component of ecological stability –
resistance or flexibility with regard to the fulfilment of the required forest functions, the time of
Forest Landscapes and Global Change - New Frontiers in Management, Conservation and Restoration. Proceedings of the IUFRO Landscape
Ecology International Conference, September 21-27, 2010, Bragança, Portugal. J.C. Azevedo, M. Feliciano, J. Castro & M.A. Pinto (eds.) 2010,
Instituto Politécnico de Bragança, Portugal.