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Estuarine. What is it?. It`s a transition zone between river environments and ocean environments . It`s where salty water ( ocean ) and fresh water ( rivers ) mix . Continuation . It`s one of the most productive habitats in the world.
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Whatis it? • It`s a transitionzone betweenriverenvironmentsandoceanenvironments. • It`swheresaltywater (ocean)andfreshwater (rivers)mix.
Continuation... • It`soneofthemostproductive habitats in the world. • It`sthe habitat ofmanymamals, birds, fishes, amongotheranimals. • It`sdistinticfromeveryotherplaceonearth, it`sirreplacable!!!
Wheredoes thishappen? • Island (separates de mainland from the island) • Barrior • Reefs • River meet ocean
OriginofEstuaries • Formedbythe flooding of river-eroded • Or glacially scoured valleys when sea level began to rise about 10,000-12,000 years ago.
Typesof it • Salt wedge : Wherefreshwaterfloatson top ofsaltywater, in a layer that gradually thins as it moves seaward. As a velocity difference develops between the two layers, generate internal waves that mix them both. A exemple would be the Missisipi River.
... • Partiallymixed As tidal forcing increases, river output becomes less than the marine input. current induced turbulence causes mixing of the water, becoming balanced. Example of it would be theChesapeake Bay and Narragansett Bay
... • Verticallyhomogenous Tidal mixing forces exceed river output, resulting in a well mixed water. The freshwater-seawater boundary is eliminated due to the intense turbulent mixing and eddy effects. Examples: Delaware Bay and the Raritan River in New Jersey.
... • Inverse: occur in dry climates where evaporation greatly exceeds the inflow of fresh water. A salinity maximum zone is formed, and both riverine and oceanic water flow close to the surface towards this zone. Example: Spencer Gulf
... • Intermittent Estuary type varies dramatically depending on freshwater input, and is capable of changing from a wholly marine embayment to any of the other estuary types.
Physiochemicalvariation • Salinity: salinity levels are generally highest near the mouth of a river where the ocean water enters, and lowest upstream where freshwater flows in. Salinity levels decline in the spring (snowmelt and rain) Salinity levels rise during the summer (increase evaporation)
Sediments: • often settles in intertidal mudflats which are extremely difficult to colonize. • vegetationbased habitat is not established. • Sediment can also clog feeding and respiratory structures of species
DissolvedOxygen • variation can cause problems for life forms • Nutrient-rich sediment from man-made sources can promote primary production life cycles, perhaps leading to eventual decay removing the dissolved oxygen from the water.
Marine Life • Estuaries provide habitats for a large number of organisms and support very high productivity. • provide habitats for many fish nurseries, (species depends on the geography of the estuarine and salinity) • Phytoplanktonare key primary producers
Phytoplankton are key primary producers, They move with the water bodies being able to be flushed in and out with the tides. • It is important to remember that a primary source of food for many organisms on estuaries, including bacteria, is detritus from the settlement of the sedimentation.
Importance • Home ofuniquespeciesofanimalsandplants • Benefitialtohumansmonetarily. • Benefitial to humans in form of recreational activities, scientific study, and aesthetic enjoyment.
Importance • Video...