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Water on Earth is in a continuous state of change. The water cycle includes processes...
The rise and drop of sea levels caused by the gravitational force of the Moon.
The dissolution of limestone results in the development of karst formations.
Atmospherical nitrogen is bound by bacteria and used by living organisms in the form of...
The oxygen cycle describes the movement of oxygen within its three main reservoirs.
This animation demonstrates different types of soil.
Water is one of our key natural resources; we must protect it vigorously.
It is characterised by dry, hot summers and mild winters.