Enviromental Polution
THE BIOSPHERE The environment (biosphere) extends to about 20 km from the bottom of the ocean to the highest point in the atmosphere at which life can survive without manmade protective devices. Biosphere contains about 1.8 million known species.
The essential requisites of life for all life forms (light, heat, water, food, and habitats) are supplied by the biosphere. Biosphere is very complex and large, so it is divided into smaller units (ecosystems). Each ecosystem consists of two parts: biotic and abiotic. Biotic category is subdivided into 3 functional groups: 1) producers: the autotrophic (self-nourishing) organisms (green plants and algae) 2) consumers: the heterotrophic organisms (all animal life) 3) Decomposers: heterotrophic organisms like bacteria and fungi that break down waste materials (including dead producers and consumers) to again make chemical components available to producers. The largest and most commonly studied phyla of animals are: 1 2 3 4 5 6 7 8 Porifera (sponges) Cnidaria (jellyfish, hydras, sea anemones, Portuguese man-of-wars, and corals) Platyhelminthes (flatworms, including planaria, flukes, and tapeworms) Nematoda (roundworms, including rotifers and nematodes) Mollusca (mollusks, including bivalves, snails and slugs, and octopuses and squids) Annelida (segmented worms, including earthworms, leeches, and marine worms) Echinodermata (including sea stars, sea cucumbers, sand dollars, and sea urchins) Arthropods (including arachnids, crustaceans, millipedes, centipedes, and
Environmental Pollution Control
1
insects) 9 Chordata (animals with nerve chords - this group includes the vertebrates)
Varieties of known species KINGDOM Bacteria Protoctists (algae, protozoa, etc) Animals, invertebrates Animals, vertebrates Birds Mammals Fungi Plants Total number of described species Estimated number of unknown species No. OF SPECIES 4,000 80,000 1,272,000 52,000 10,000 45000 72,000 270,000 1,750,000 14,000,000
[UNEP-WCMC (2000).
The essential requisites of life for all life forms (light, heat, water, food, and habitats) are supplied by the biosphere. Biosphere is very complex and large, so it is divided into smaller units (ecosystems). Each ecosystem consists of two parts: biotic and abiotic. Biotic category is subdivided into 3 functional groups: 1) producers: the autotrophic (self-nourishing) organisms (green plants and algae) 2) consumers: the heterotrophic organisms (all animal life) 3) Decomposers: heterotrophic organisms like bacteria and fungi that break down waste materials (including dead producers and consumers) to again make chemical components available to producers. The largest and most commonly studied phyla of animals are: 1 2 3 4 5 6 7 8 Porifera (sponges) Cnidaria (jellyfish, hydras, sea anemones, Portuguese man-of-wars, and corals) Platyhelminthes (flatworms, including planaria, flukes, and tapeworms) Nematoda (roundworms, including rotifers and nematodes) Mollusca (mollusks, including bivalves, snails and slugs, and octopuses and squids) Annelida (segmented worms, including earthworms, leeches, and marine worms) Echinodermata (including sea stars, sea cucumbers, sand dollars, and sea urchins) Arthropods (including arachnids, crustaceans, millipedes, centipedes, and
Environmental Pollution Control
1
insects) 9 Chordata (animals with nerve chords - this group includes the vertebrates)
Varieties of known species KINGDOM Bacteria Protoctists (algae, protozoa, etc) Animals, invertebrates Animals, vertebrates Birds Mammals Fungi Plants Total number of described species Estimated number of unknown species No. OF SPECIES 4,000 80,000 1,272,000 52,000 10,000 45000 72,000 270,000 1,750,000 14,000,000
[UNEP-WCMC (2000).