Values, Alterations and Degradation of the Natural Landscape 87
with the gradual perturbation of the biochemical cycles and the significant degradation of the productive capacity of certain natural resources.
Energy consumption, a symbol of the industrial era, constituted the main
perturbations’ source, and in combination with the new massive production
processes, caused the accumulation of all kinds of waste and the pollution
phenomenon at a global level. At the same time, alterations of the natural
environment and over exploitation of natural resources (e.g. over fishing)
that had begun in previous periods were intensified, resulting in accelerated
decrease and degradation of biodiversity, of the forest cover of many terrestrial and marine ecosystems and of natural landscapes and seascapes.
By the late 20th century, the beginning of a meta-industrial era that came
dimly into sight with the new millennium gradually created a new frame for
human activities, where the dilemma between development and environmental protection came to the foreground (Chapter 13).
5.2 tErrEStrial EcoSyStEMS
Terrestrial ecosystems can be divided, mainly on the basis of the prevailing vegetation type, in four basic categories: forest, grassland, desert and
tundra. The forest is divided into the sub-categories temperate, tropical and
northern forest. There are also other categories of lands covered by high
natural vegetation that are characterized by a smaller expansion, such as
scrubs of temperate marine climates with winter rainfalls (Mediterranean
basin, coasts of California and Chile, regions of Australia). The type distribution of terrestrial ecosystems in the planet’s surface is determinatively
dependent on the average temperature and average rainfall of each area.
5.2.1 Forest Ecosystem
tionally wide, a series of forest types succeed one another in different geographic latitudes. Forest ecosystems correspond also to a wide range of
humidity values, from dry to very humid regions.
Further north of the northern hemisphere’s temperate forests, a wide
forest zone is formed, called taiga. It mainly consists of coniferous trees
of the Pinus, Picea and Abies genera. Diversity is small; usually only one
or two tree species dominate, while rarely can one find deciduous trees. In
this forest zone that surrounds the planet, approximately one-fourth of the
biomass and perhaps half of the biosphere’s carbon is contained; therefore
it constitutes a large store for the surplus of CO 2 that is produced by human
activities. The influence of this zone on the climate and the air renewal
of the northern temperate regions is also significant. Some characteristic
species of big mammals (bears, wolves, deer, reindeer) live in the taiga.
with the gradual perturbation of the biochemical cycles and the significant degradation of the productive capacity of certain natural resources.
Energy consumption, a symbol of the industrial era, constituted the main
perturbations’ source, and in combination with the new massive production
processes, caused the accumulation of all kinds of waste and the pollution
phenomenon at a global level. At the same time, alterations of the natural
environment and over exploitation of natural resources (e.g. over fishing)
that had begun in previous periods were intensified, resulting in accelerated
decrease and degradation of biodiversity, of the forest cover of many terrestrial and marine ecosystems and of natural landscapes and seascapes.
By the late 20th century, the beginning of a meta-industrial era that came
dimly into sight with the new millennium gradually created a new frame for
human activities, where the dilemma between development and environmental protection came to the foreground (Chapter 13).
5.2 tErrEStrial EcoSyStEMS
Terrestrial ecosystems can be divided, mainly on the basis of the prevailing vegetation type, in four basic categories: forest, grassland, desert and
tundra. The forest is divided into the sub-categories temperate, tropical and
northern forest. There are also other categories of lands covered by high
natural vegetation that are characterized by a smaller expansion, such as
scrubs of temperate marine climates with winter rainfalls (Mediterranean
basin, coasts of California and Chile, regions of Australia). The type distribution of terrestrial ecosystems in the planet’s surface is determinatively
dependent on the average temperature and average rainfall of each area.
5.2.1 Forest Ecosystem
tionally wide, a series of forest types succeed one another in different geographic latitudes. Forest ecosystems correspond also to a wide range of
humidity values, from dry to very humid regions.
Further north of the northern hemisphere’s temperate forests, a wide
forest zone is formed, called taiga. It mainly consists of coniferous trees
of the Pinus, Picea and Abies genera. Diversity is small; usually only one
or two tree species dominate, while rarely can one find deciduous trees. In
this forest zone that surrounds the planet, approximately one-fourth of the
biomass and perhaps half of the biosphere’s carbon is contained; therefore
it constitutes a large store for the surplus of CO 2 that is produced by human
activities. The influence of this zone on the climate and the air renewal
of the northern temperate regions is also significant. Some characteristic
species of big mammals (bears, wolves, deer, reindeer) live in the taiga.