92 Ecology and Applied Environmental Science
still the effort for the creation of agricultural land, while other significant
causes are the demand for firewood for cooking and heating, the creation of
pastures for livestock farming, and the exploitation of tradable timber. The
change of land use and fires constitute threats for certain forests of countries with a temperate climate, whereas recently, the forests of Northern
and Central Europe faced the acid rain threat.
Coping with major global problems, such as the greenhouse threat,
erosion, desertification, water shortage and energy deficiency, requires a
gigantic effort for upgrading the planet’s forests. Programmes are needed
sive reforestation of areas that have suffered deforestation, and for forestation (creation of new forests) in areas where other uses are not necessary.
It is estimated that an immediate forest restoration is required, especially in
tropic areas, in a stretch of at least 150 million hectares. A basic necessary
resource for this endeavour is not only the capital but also work, which
only the local farmers can provide on such a scale.
5.2.6 natural vegetation in a
Mediterranean Environment
5.2.6.1 Forests
Pine forests of low altitudes occur from the coastal areas up to 1200 m; they
include several species of pine, cypresses or cedars. These forests develop
in Mediterranean climatic conditions and are extremely vulnerable to fires.
In low altitude areas, with more humidity and lower winter temperatures, mixed deciduous forests develop that include mainly various species
of oaks.
In stream beds, on river banks and on lake shores as well as in lowland
areas with high humidity, like river mouths, hydrophilous clusters of trees
develop, such as plane-trees, poplars, willows and tamarisks. The latter
often appear along beaches as well.
Mountain forests mostly occur between 500 and 2000 m, in climatic
tures, snowfall and frequent rainfall. They are distinguished into coniferous forests that mainly include Pinus nigra and species of firs, and into
deciduous forests that include beech in higher altitudes and various species
of oak or other trees in lower places.
During the past century, forest cover of many European countries has
increased; for example, in Greece, it exhibits an ascending course in the last
decades, given that the percentage of forests had previously been estimated
as 19%. In spite of the limited reliability of the old estimations, the comparison reveals that the destruction of woodland due to fires, over-grazing
etc. has been overbalanced in our days either by the natural regeneration
still the effort for the creation of agricultural land, while other significant
causes are the demand for firewood for cooking and heating, the creation of
pastures for livestock farming, and the exploitation of tradable timber. The
change of land use and fires constitute threats for certain forests of countries with a temperate climate, whereas recently, the forests of Northern
and Central Europe faced the acid rain threat.
Coping with major global problems, such as the greenhouse threat,
erosion, desertification, water shortage and energy deficiency, requires a
gigantic effort for upgrading the planet’s forests. Programmes are needed
sive reforestation of areas that have suffered deforestation, and for forestation (creation of new forests) in areas where other uses are not necessary.
It is estimated that an immediate forest restoration is required, especially in
tropic areas, in a stretch of at least 150 million hectares. A basic necessary
resource for this endeavour is not only the capital but also work, which
only the local farmers can provide on such a scale.
5.2.6 natural vegetation in a
Mediterranean Environment
5.2.6.1 Forests
Pine forests of low altitudes occur from the coastal areas up to 1200 m; they
include several species of pine, cypresses or cedars. These forests develop
in Mediterranean climatic conditions and are extremely vulnerable to fires.
In low altitude areas, with more humidity and lower winter temperatures, mixed deciduous forests develop that include mainly various species
of oaks.
In stream beds, on river banks and on lake shores as well as in lowland
areas with high humidity, like river mouths, hydrophilous clusters of trees
develop, such as plane-trees, poplars, willows and tamarisks. The latter
often appear along beaches as well.
Mountain forests mostly occur between 500 and 2000 m, in climatic
tures, snowfall and frequent rainfall. They are distinguished into coniferous forests that mainly include Pinus nigra and species of firs, and into
deciduous forests that include beech in higher altitudes and various species
of oak or other trees in lower places.
During the past century, forest cover of many European countries has
increased; for example, in Greece, it exhibits an ascending course in the last
decades, given that the percentage of forests had previously been estimated
as 19%. In spite of the limited reliability of the old estimations, the comparison reveals that the destruction of woodland due to fires, over-grazing
etc. has been overbalanced in our days either by the natural regeneration