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:
Earth, Mars
Explanation:
Earth is the only planet on which life is known to exist. Water on earth exists in all three forms
Presence of water on Mars was recently confirmed. Though liquid water is no more present, in solid form, water is present in polar ice caps.
