Water regenerates itself

When polluted, fresh water basins have the capacity to self-clean their water, i.e. to make the water return to its original quality and purity. This self-cleaning phenomenon is provoked by bacteria that, in the presence of oxygen, degrade and transform the polluting substances into inert inorganic compounds. Obviously this process is not effective on all types of pollutants and for any amount of polluting substances present in the water. In some cases, human intervention is necessary to clean the water reserves that have been polluted. The type of treatment that must be used to clean the water depends essentially on the type of pollutant that must be eliminated. The greater the number of pollutants in the water, the more difficult it is to clean it. In some cases polluted water is extracted, purified and then returned to the water table, river or lake. In other cases water is purified on site (i.e. without removing the water from its natural site). Also the sea has a great self-regenerating capacity, which can neutralize human polluting actions. However, if human activities continue to persevere in an uncontrolled and unsustainable exploitation of a resource that seems (but is not) inexhaustible, this regenerating capacity will cease and it will permanently jeopardize the sea’s capacity to correctly carry out all the vital functions that it provides today. Man is now aware of this and is increasingly aware of the mechanisms that regulate the water cycle , that allow rivers, lakes, seas and oceans to live. Therefore we know where and how to intervene: the problem is to succeed in improving and spreading good practices and sustainable use of the water resource all over the world, in our communities and in those countries where respect for natural resources seems to be applicable only to the richer countries.

Special reports

  • 15 April 2014

    How rich are we …. in blue gold?

    Water footprint, water availability and use on a planetary scale...

    26 February 2014

    How much water is on your plate?

    Water footprint and water consumption...

    8 July 2022

    Who’s coming to dinner

    A shark in my hamburger Summer is finally here! As usual, we have waited for it all year long and…

  • 10 February 2020

    Coral turns pale!

    The coral reef is one of the ecosystems with the richest biodiversity...

    13 May 2018

    Small steps, great footprints

    Have you ever wondered how much space is taken up by an apple or a steak?...

    7 October 2021

    Water grabbing

    “Clear, sweet fresh water,” wrote Petrarch, by many considered a precursor of Italian literature. Before him, St. Francis dedicated two…

  • 17 May 2021

    Lost ice

    According to a study conducted by a French and Swiss research team recently published in the leading journal Nature, continental…

    15 April 2021

    Oceans of plastic

    The invisible invasion of microplastics...

    26 December 2019

    Life in Antarctica

    How is it possible to live and work in Antarctica...

From the Multimedia section

  • water

    Map of water scarcity

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    water

    Availability of water resources

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    life

    Algae proliferation

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  • water

    Water and man

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    water

    Water and sustainability

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    water

    Components of the water footprint

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  • air

    The polar bear will become extinct

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    life

    Algae living in heavily polluted

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    air

    Desertification

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  • water

    Map of water scarcity

    Look

    water

    Availability of water resources

    Look
  • life

    Algae proliferation

    Look

    water

    Water and man

    Listen
  • water

    Water and sustainability

    Listen

    water

    Components of the water footprint

    Look
  • water

    Map of water scarcity

    Look
  • water

    Availability of water resources

    Look
  • life

    Algae proliferation

    Look

Facts

  • 16 May 2011

    The “wave-swallowing” dragon

    Wave Dragon, that swallows waves and generates electricity is a plant...

    13 May 2011

    Niño and Niña

    The Humbolt ocean current goes north along the Peruvian coasts and...

  • Water as a percentage

    Only 3% of total water reserves is made up of fresh water...

    Water in the human body

    In some organisms, water can compose up to 90% of their total weight...

  • 11 May 2011

    Sea in love

    In Italy, the "mare in amore" phenomenon occurs very often: the part of the sea coast where this occurs is…

    16 May 2011

    Ephemeral lakes

    Even big lakes can form on the surface, inside or at the contact with...