Man stands at the top of the ecological pyramid. He is an omnivore – a tertiary consumer, consuming both plants and animals.
The negative impact of humans on the biosphere
(i) The growth in human population and industrialization has resulted in the extinction of a number of flora and fauna by deforestation.
(ii) Clearing the natural vegetation and its replacement by a single crop has reduced the biological diversity and the single crop has become susceptible to pests and insects.
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(iii) Burning of fossil fuels, automobile exhausts, gaseous effluents from factories have led to pollution of land, air and water and its related consequences.
(iv) Hunting of animals and birds and introduction of new predators in the environment has caused extinction of some species.
The positive impact of humans on the biosphere
(i) Humans are responsible for the introduction of new species of plants from one part of the world to another; for example, rubber from the Amazon Basin of Brazil was brought to Malaysia, which is now the world’s largest producer of rubber.
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(ii) By selective breeding, he has improved the yields of crops.
(iii) By domesticating animals he has protected them from their predators.
(iv) New breeds of cattle have been developed which give much higher yields.
(v) He has made his life comfortable by using the natural resources.