The accessible components of environment are:
Atmosphere
This is a blanket of gaseous layer around the Earth.
Hydrosphere
This includes all sources of water like oceans, rivers, lakes, glaciers, ground water, etc. and comprises about 96% of Earth's surface.
Lithosphere
This comprises of soil, minerals, organic matter etc. and refers to Earth's solid crust containing the outer mineral cover.
Biosphere
This is the domain of living organisms in contact with atmosphere, hydrosphere as well as lithosphere.
Man has begun to effect significant changes in his natural environment mainly after the advent of the Industrial revolution. The change in industrial and agricultural practices in the last 300 years and the direction of overall economic, technological and institutional development, has led to a tremendous increase in the use of energy and its impact on the environment.Due to these climatic changes, health hazards, effects on food and water supplies, changing habitats and eco-systems are effecting plants and animals life. Effects on the environment such as ozone depletion, greenhouse effect, acid rains, etc. have surfaced in recent years and are often the hot topics of discussion.
The branch of chemistry, which deals with the study of various chemical phenomena occurring in the environment, is called environmental chemistry. It is a multidisciplinary science that refers to the study of sources and effect of certain chemical species on air, water and soil.