Aquatic snails residing in flooded rice paddies feed on bacterial communities known as__________________?
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Answer: C. Azolla
Explanation
Aquatic floating ferns known as Azolla form symbiotic relationships in flooded rice paddies. Azolla hosts nitrogen-fixing cyanobacteria within specialized cavities inside its fronds. These aquatic systems naturally enrich paddy water with biologically fixed nitrogen nutrients. Flooded rice paddies provide ideal wetland environments for various aquatic plants and animals. Biological nitrogen fixation reduces the need for synthetic chemical fertilizers in agriculture. Symbiotic associations between plants and microbes are vital for sustainable ecosystem functioning.
Farmers use Azolla as a green manure to boost soil fertility and rice crop yields. Aquatic organisms in rice paddies contribute to complex ecological food webs and nutrient cycles. Sustainable farming practices encourage biological nitrogen inputs to protect surrounding water resources. Helix refers to a genus of land snails rather than the floating aquatic fern Azolla. Limnea represents a genus of freshwater snails feeding on algae rather than nitrogen-fixing ferns. Option D is incorrect because Azolla correctly identifies the organism mentioned.
- Subject
- Agriculture
- Category
- Agriculture
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- —
- Difficulty
- medium
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