The abiotic factor that is essential for all aquatic ecosystem with the exception of hydro thermal vent is SUNLIGHT, THIS IS BECAUSE IT PROVIDES A SOURCE OF ENERGY.
Sunlight is very essential for aquatic ecosystems because it is the principal source of energy from which aquatic plants trap energy to make their food and provided mean of sustenance for themselves and other organisms in the water.
Answer: A niche is the role an organism plays in the ecosystem.
Explanation: A niche also determines how the organism interacts with other organisms in an ecosystem
I believe blood vessels constrict
South America, Brazil, Canada, And Hawaii
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