Like rivers, seas are closely connected
to human activities and history.
The main activities related to the
sea are:
Navigation
Since the
beginning of history, the sea has
been used for travel, for exploring
the world, trade or war.
Today, it is used mostly as a
means to transport people and
merchandise (transatlantic ships,
oil tankers and cargo ships).
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3. Water on the Earth
4. THE IMPORTANCE OF RIVERS AND SEAS
FOR HUMANS
Humans, like plants and animals, need fresh water to live. This water comes mainly
from rivers. For this reason, most cities are located next to a river. For example,
Toledo – the
Tajo
; Seville – the
Guadalquivir
; Zaragoza – the
Ebro
; Rome – the
Tiber
; Paris – the
Seine
.
However, many cities are located at the river mouth in order to have access to a
port and have contact with people who live inland, further up the river. For example,
Lisbon – the
Tajo
; Valencia – the
Turia
; London – the
Thames
; New Orleans – the
Mississippi
; Alexandria – the
Nile
; Buenos Aires –
Río de la Plata
.
Rivers form valleys covered with sediments that they deposit, fertilising the land.
People settled in these valleys and agriculture developed. The oldest civilisations
grew around big rivers: Egypt, next to the
Nile
; Mesopotamia, along the
Euphrates
and the
Tigris
; India, on the banks of the
Ganges
and the
Indus
.
Rivers also provide energy for human activities. In the past, water was used to power
by mills. Today, water is used to produce electricity in hydroelectric stations. Rivers are
also used as a means of communication when flow rate and depth allow navigation.
Water is also extracted for use by industry and for recreation, such as water parks and
gardens.
Alcántara (Cáceres), Roman bridge over the Tajo River and dam
Rivers
and
seas
have been essential to human development, and still are
today. The majority of the
world’s population
lives on the
coasts
or next
to
rivers.
4
breed
:
produce animals from existing
ones.
