aquatic life unit 1, topic 2. 1 aquatic habitats vary in characteristics streams rivers ponds lakes...
TRANSCRIPT
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Aquatic flora• Ecological requirements
• Types:Sunlight, carbon dioxide, oxygen, nutrients, space
Microscopic photosynthetic protists
Macroscopic photosynthetic protists
Plants
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Aquatic fauna
• Ecological requirements
• Types:–Microfauna (microscopic plankton)–Macrofauna (invertebrates and vertebrates)
Oxygen, space, plants, habitat, tolerance limits
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Indicator Species: Biological Smoke Alarms
• Species that serve as early warnings of damage to a community or an ecosystem.– eg: Presence or absence of trout species in freshwater bodies because they are sensitive to temperature and oxygen levels.
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Indicator species: Amphibians
• Frogs serve as indicator species because different parts of their life cycles can be easily disturbed.
Figure 7-3Figure 7-3
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Why are Amphibians Vanishing?
• Habitat loss and fragmentation.• Prolonged drought.• Pollution.• Increases in ultraviolet radiation.• Parasites.• Viral and Fungal diseases.• Overhunting.• Natural immigration or deliberate introduction of nonnative predators and competitors.
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Invertebrate indicators
• Macroinvertebrates are good measures of longterm water quality
• Broadly classify as “sensitive”, “somewhat tolerant”, and “pollution tolerant”
• Scenarios:– We only find organisms that are “tolerant”. What can we definitively say about the longterm water quality?
– We find numerous individuals of a species that is “sensitive” to pollution and many individuals of various species that are “tolerant”. What can we definitively say about the longterm water quality?