154
Chapter 17
3.2
Ecological needs
Forest inventories have traditionally provided information related to the
biological diversity of forests, such as the structure of growing stock, areas
of site fertility classes and sometimes the distribution and abundance of plant
species. An increasing concern about the loss of diversity, caused by, e.g.,
deforestation, human induced environmental and climate changes as well as
the extinction of species, has promoted interest in the whole forest
ecosystem and its biological diversity. It has been estimated that the present
extinction rate is 100–10,000 times higher than would occur naturally. There
is wide agreement that some components and indicators of forest
biodiversity can only be measured efficiently in the context of large area
inventories. Examples of such components or indicators are the composition
and structure of landscape, the existence of ‘ecological corridors’ between
different habitat types, the fragmentation of forests or land types, the areas
and spatial distributions of important habitat types which support rich flora
and fauna, as well as the amount of rotting wood in the Boreal zone.
3.3
Carbon fixation
Forests have also been seen as having a role in reducing the effects of
global warming by sequestering some of the increasing amount of carbon
dioxide in the atmosphere for periods of years (Kauppi et al. 1995). It has
been estimated that the current forest area is only one half of the area that
was forested 8000 years ago (under hypothetical similar climate conditions).
The total carbon release in the beginning of 1990s was 6.2 gigatons. The
estimated carbon storage in the world’s trees is 360 gigatons. The recent
annual carbon flux to trees is not well known because tree growth estimates
for the whole Earth are unreliable. However, the figures 1±1 gigatons per
year are often given. A proper use of wood resources and an increase of
forest area have a good potential to decrease the amount of atmospheric
3.4
Forest health monitoring needs
Industrialization has resulted in transboundary air pollution effects. For
several decades, acidic deposition has threatened forest trees and soil, as well
as other environmental components, especially in Central and Eastern
Europe. Awareness of wide area forest damages caused by air pollution
arose at the beginning of the 1970s. As a result, more recent inventories and
wide forest health monitoring programs have gathered information on new
Chapter 17
3.2
Ecological needs
Forest inventories have traditionally provided information related to the
biological diversity of forests, such as the structure of growing stock, areas
of site fertility classes and sometimes the distribution and abundance of plant
species. An increasing concern about the loss of diversity, caused by, e.g.,
deforestation, human induced environmental and climate changes as well as
the extinction of species, has promoted interest in the whole forest
ecosystem and its biological diversity. It has been estimated that the present
extinction rate is 100–10,000 times higher than would occur naturally. There
is wide agreement that some components and indicators of forest
biodiversity can only be measured efficiently in the context of large area
inventories. Examples of such components or indicators are the composition
and structure of landscape, the existence of ‘ecological corridors’ between
different habitat types, the fragmentation of forests or land types, the areas
and spatial distributions of important habitat types which support rich flora
and fauna, as well as the amount of rotting wood in the Boreal zone.
3.3
Carbon fixation
Forests have also been seen as having a role in reducing the effects of
global warming by sequestering some of the increasing amount of carbon
dioxide in the atmosphere for periods of years (Kauppi et al. 1995). It has
been estimated that the current forest area is only one half of the area that
was forested 8000 years ago (under hypothetical similar climate conditions).
The total carbon release in the beginning of 1990s was 6.2 gigatons. The
estimated carbon storage in the world’s trees is 360 gigatons. The recent
annual carbon flux to trees is not well known because tree growth estimates
for the whole Earth are unreliable. However, the figures 1±1 gigatons per
year are often given. A proper use of wood resources and an increase of
forest area have a good potential to decrease the amount of atmospheric
3.4
Forest health monitoring needs
Industrialization has resulted in transboundary air pollution effects. For
several decades, acidic deposition has threatened forest trees and soil, as well
as other environmental components, especially in Central and Eastern
Europe. Awareness of wide area forest damages caused by air pollution
arose at the beginning of the 1970s. As a result, more recent inventories and
wide forest health monitoring programs have gathered information on new