Sub-topic 1
2025 · National Preliminary
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Estuaries: mixing zone of fresh and salt water
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Sub-topic 2
2025 · National Preliminary
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Pond as a freshwater habitat with slow water and abundant aquatic plants
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Sub-topic 3
2025 · National Semifinal
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Marine heatwaves: persistent anomalously warm ocean temperatures
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Sub-topic 4
2024 · National Semifinal
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Brackish water: salinity intermediate between fresh water and seawater
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Sub-topic 5
2025 · National Quarterfinal
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Role of green plants in an aquarium ecosystem
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Sub-topic 6
2023 · National One-Eighth
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Riddle: zooplankton
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Sub-topic 7
2013 · National Preliminary
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Problem of the day: structural adaptations of plants to aquatic habitats
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Sub-topic 8
2016 · National One-Eighth
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Turbidity as the abiotic factor controlling light penetration depth in water
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Sub-topic 9
2017 · National Quarterfinal
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Riddle: the intertidal zone, exposed at low tide and submerged at high tide
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Sub-topic 10
2022 · National Preliminary
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Benthic vs pelagic zones distinguished by light and temperature
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Sub-topic 11
2022 · National Preliminary
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Benthic vs pelagic zones distinguished by nourishment and resources
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Sub-topic 12
2022 · National Preliminary
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Benthic vs pelagic zones distinguished by food sources for organisms
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