146
marine law, economic regulation and other preventive measures. For this the environmental attitude of decision makers in states, fishing, trade
and marine transport companies has to be developed. Moreover, everyone involved in the environmentally sound use of the sea has to be made
interested with all measures of economic
regulation.
4.3.3 State of Fresh Waters
Fresh water suitable for humans can be found in
the water systems of rivers and lakes and also in
geological formations (different types of groundwater). Today, humans are able to extract all of
them using modern technology. And as a matter
of fact we humans do extract these waters
intensely and utilise them for various purposes.
Initially the easily accessible surface waters
were utilised thus discussing the current state of
waters is started with them.
4.3.3.1 Surface Water
Three major sources of danger regarding the surface water systems of continents are highlighted:
• overuse of water and associated dam
construction,
• pollution of water,
• climate change.
In many cases the above reasons occur
together and their joint effects could have serious
consequences on both the natural environment
and the society.
Water overuse can be related to both surface
drainage networks and subsurface water bases.
The latter will be discussed in the next chapter
(Sect. 4.3.3.2). Humans so far utilised surface
waters in higher ratio and these are still the dominant fresh water sources.
Water is used for various purposes. Fresh
water has been used for agricultural purposes in
greatest ratio, mostly for irrigation. It is no surprise that the first civilizations developed along
major rivers (Egypt—Nile, Mesopotamia—
Tigris, Euphrates; Indus Valley—Ganges,
China—Yangtze) as their water could be used for
irrigating land.
Today is no different as agriculture consumes
water the most; however, the quantity depends on
the climate and the development and technical
possibilities of the given society. Globally around
60% of the total used fresh water is demanded by
agriculture. This is why the advancement of
water saving irrigation methods is important
(Box 4.6). Regarding industrial establishments
power plants use the greatest amount of water for
Box 4.6 Every Drop Is Value
In many regions on Earth severe lack of
water already makes life difficult. Under
arid or semi-arid climate crop production
requires most water considering human
activities. Next to providing drinking water
irrigating crop is the most important in
order to provide fundamental food for
locals. Irrigation practice proved that the
irrigation technique significantly influences the quantity of water used. Drip irrigation instead of spray irrigation (that
requires high performance pumps as well)
uses 40–50% less water for roughly the
same result.
In semi-arid regions of Africa or in
Monsoon areas of India the more effective
use of the limited water resources is as
essential for small-scale farmers in the dry
period as access to water. For meeting this
demand a series of cheap micro-irrigation
technologies has been developed from
5-dollar buckets to 100-dollar mobile drip
systems (Postel 2011). The common feature of these systems is that they drip irrigation water with small intensity directly
onto the soil in the root zone of plants
where water immediately filtrates into
deeper layers reducing evaporation loss to
a minimum. International Development
Enterprises (IDE, a Denver based nonprofit organisation) has sold more than
600,000 cheap drip systems in India, Nepal,
4 Changes on Earth as a Result of Interaction Between the Society and Nature
marine law, economic regulation and other preventive measures. For this the environmental attitude of decision makers in states, fishing, trade
and marine transport companies has to be developed. Moreover, everyone involved in the environmentally sound use of the sea has to be made
interested with all measures of economic
regulation.
4.3.3 State of Fresh Waters
Fresh water suitable for humans can be found in
the water systems of rivers and lakes and also in
geological formations (different types of groundwater). Today, humans are able to extract all of
them using modern technology. And as a matter
of fact we humans do extract these waters
intensely and utilise them for various purposes.
Initially the easily accessible surface waters
were utilised thus discussing the current state of
waters is started with them.
4.3.3.1 Surface Water
Three major sources of danger regarding the surface water systems of continents are highlighted:
• overuse of water and associated dam
construction,
• pollution of water,
• climate change.
In many cases the above reasons occur
together and their joint effects could have serious
consequences on both the natural environment
and the society.
Water overuse can be related to both surface
drainage networks and subsurface water bases.
The latter will be discussed in the next chapter
(Sect. 4.3.3.2). Humans so far utilised surface
waters in higher ratio and these are still the dominant fresh water sources.
Water is used for various purposes. Fresh
water has been used for agricultural purposes in
greatest ratio, mostly for irrigation. It is no surprise that the first civilizations developed along
major rivers (Egypt—Nile, Mesopotamia—
Tigris, Euphrates; Indus Valley—Ganges,
China—Yangtze) as their water could be used for
irrigating land.
Today is no different as agriculture consumes
water the most; however, the quantity depends on
the climate and the development and technical
possibilities of the given society. Globally around
60% of the total used fresh water is demanded by
agriculture. This is why the advancement of
water saving irrigation methods is important
(Box 4.6). Regarding industrial establishments
power plants use the greatest amount of water for
Box 4.6 Every Drop Is Value
In many regions on Earth severe lack of
water already makes life difficult. Under
arid or semi-arid climate crop production
requires most water considering human
activities. Next to providing drinking water
irrigating crop is the most important in
order to provide fundamental food for
locals. Irrigation practice proved that the
irrigation technique significantly influences the quantity of water used. Drip irrigation instead of spray irrigation (that
requires high performance pumps as well)
uses 40–50% less water for roughly the
same result.
In semi-arid regions of Africa or in
Monsoon areas of India the more effective
use of the limited water resources is as
essential for small-scale farmers in the dry
period as access to water. For meeting this
demand a series of cheap micro-irrigation
technologies has been developed from
5-dollar buckets to 100-dollar mobile drip
systems (Postel 2011). The common feature of these systems is that they drip irrigation water with small intensity directly
onto the soil in the root zone of plants
where water immediately filtrates into
deeper layers reducing evaporation loss to
a minimum. International Development
Enterprises (IDE, a Denver based nonprofit organisation) has sold more than
600,000 cheap drip systems in India, Nepal,
4 Changes on Earth as a Result of Interaction Between the Society and Nature