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18.10.2015, 22:20 | |
Environment and its Changing The life of every
living organism, from the simplest bacterium to the largest animal, is known
to depend on the structure and physiology of the living organism and also on
the kind of the environment it lives in. Physical and
biological factors act to make a wide variety of environments in different
parts of the world. Conditions are rather constant in some tropical lands and
seas, but over much of the Earth the temperature and moisture relations and
sunlight change markedly with the season. The life of each
plant or animal species is closely connected with the life of plants or
animals of other species. No animal lives entirely to itself. On the contrary,
each is part of an integrated living community that includes representatives of
its kind, many different types of animals and plants of few or many kinds. Animals and plants
are affected by various physical and chemical factors, the most important being
sunlight, temperature, water, physical substrate, gases and some others. All
the factors mentioned are interrelated and none acts independently. Sunlight provides
energy used by plants in photosynthesis, but it also warms animal environment
and animals themselves. Sunlight raises the temperature of water leading to
evaporation which in turn results in
precipitation of rain and snow. Water is the
solvent for soil nutrients used by plants as food. It is a necessity for
maintaining animal life and is the medium in which many animals live. It is interesting
to note that attempts to change the weather processes over wide areas have not
had much success. However, it is possible to make some changes in the microclimate,
that is, in the environment near the organisms. Most of the methods used are
aimed at changing either the water balance or the heat balance of an area. As
these two things are interrelated, a change in one results in a change in the
other. For example, the use of greenhouses or different materials to cover the
soil changes the heat balance of an area and leads to different requirements for
water. In addition to
changing the local climate, one can discover and develop those useful plants
and animals that grow best in the given environment, and restrict or destroy
those that are harmful. Considerable progress has been made in breeding suitable
plants and animals and in this way it is possible to extend the production
into areas they have not grown before.
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