Neuston - Environment Notes

Neuston, also called pleuston, is a group of organisms that live on the surface of the ocean, an estuary, a lake, river, or pond. Neuston can live on top of the water's surface or on the underside of it. They could also be found in the surface microlayer that arises between the top and bottom sides of the surface. Whirligig beetles and water striders are among the insects found in the neuston, as are several spiders and protozoans, as well as worms, snails, insect larvae, and hydras. It is distinct from plankton, which becomes linked with the surface coating through possibility. This article will explain to you Neuston about which will help prepare the Environment syllabus for the UPSC Civil service exam.

Water Strider, a common freshwater neuston

Neuston - Distribution

• One of the less well-known aquatic biological groups is the neuston of the surface layer.
• The term neuston was coined by Naumann in 1917 to characterize organisms found in freshwater ecosystems' surface layers.
• Sunlight and a variety of endogenous (organic matter, respiratory, photosynthetic, decompositional processes) and exogenous (atmospheric deposition, inorganic matter, winds, wave action, precipitation, UV radiation, oceanic currents, surface temperature) variables and processes influence nutrient inputs and recycling.

Presence of Neuston in the Aquatic Ecosystem

Neuston - Types

Based on the Niche of Neustons

• Epineuston: organisms that live on the surface of the water.
• Hyponeuston: organisms within a particular depth directly beneath the surface layer (hyponeuston).
• Microlayer neuston: Organisms (microorganisms) that live in the surface microlayer, which is sandwiched between the upper and lower surfaces.

Based on the Concentration of Neustons

• Euneuston: creatures that are most abundant near the surface on which they spend the most of their time.
• Facultative neuston: Organisms that cluster at the surface only at particular hours of the day, usually when it's dark.
• Pseudoneuston: Pseudoneustons are creatures that have their highest concentrations in deeper strata yet reach the surface layer at least once every few hours.

Neuston - Significance

• The neuston is a vital ecosystem that has an impact on other ocean systems.
• The neuston, like a reef or the shallow banks, acts as a nursery for some fish, making it a perfect location for other species like leatherback turtles, octopuses, and other fish to hunt for easy food.
• The neuston also serves as a food source for zooplankton traveling from deeper layers to the surface, as well as seabirds flying above the oceans.

Conclusion

The neustonic community is thought to play a crucial role in the structure and function of marine food webs for all the above reasons. However, neuston complexity remains poorly understood, with few studies on the community structure and taxonomic mix of animals. Thus it inhabits this (neuston’s) ecological niche and has no global-scale analysis.