Geoscience Reference
In-Depth Information
Table 8.1 (continued)
Ecosystem
Human life support
Regulation of the state of the environment and
human life support
Grass
ecosystems
Domestic animals
Water for drinking and
reclamation
Genetic resources
Maintaining the functions of watersheds
(in
ltration, water cleaning, regulation of
run-offs, stabilization of soil properties)
Cycles of nutrients
Removal of atmospheric pollutants and
formation of oxygen
Biodiversity maintenance
Soil formation
Accumulation of carbon from the atmosphere
Provision of habitat for humans and animals
Provision of places for recreation and
aesthetic satisfaction
ones have not only changed the traditional way of people
'
s life but also caused a
de
cit of wood fuel and timber to the detriment of 275 millions of rural population.
As for the estimates of the consequences of the global anthropogenic impacts,
the situation with the water resources is an example: about 28 % of the global
population have no access to pure drinking water; every year about 5 million people
die because of drinking low quality water and anti-sanitary conditions; about 90 %
of wastes in the developing countries go to rivers, lakes, and coastal regions of the
seas, etc. Intensi
ed emissions of CO
2
into the atmosphere have caused consider-
able changes in the global carbon cycle (Demirchian and Kondratyev 2004;
Kondratyev et al. 2003c; Field et al. 2004; Archer 2010).
The most important fact is that the levels of impact on the ecosystems have
become of a global scale. About 75 % of marine
fish populations have either
decreased due to violation of the permissible amounts of catch or come close to the
threshold of their survival. An intensive forest cutting has almost halved the for-
ested areas, and the construction of various economic infrastructures has caused a
fragmentation of the forest cover (Kaiser 2000; Keller et al. 2001). About 58 % of
coral reefs are seriously affected by
fishery, tourism, and pollution. Almost 65 % of
arable lands have partially lost their fertility. The scales of economic usage of
ground waters exceed the rate of their natural recovery by at least 160
10
9
m
3
/
×
year. In most cases the anthropogenic load on the ecosystems has intensi
ed. This
especially concerns the pasture ecosystems where the interference of the human
'
s
factor has reached the level of direct control (Schulte 2003; Schulte et al. 2003).
It is well known that the main causes of ecosystems
degradation are the growing
size of population and, respectively, increased needs for natural resources as well as
enhancing loads on the environments (Table
8.2
). Concrete detailed data charac-
terizing the present global situation can be found in numerous publications
(Kondratyev 1998a, 1999, 2000a; A Guide
'
2000; Watson et al. 2000). It is
notable that the strongest geographical non-uniformly of the growing scales of
…
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