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Svi znamo da je morska voda slana, ali jeste li se ikad zapitali zašto? Nije li čudno da je morska (oceanska) voda uvijek slana, a druge vode poput jezera i rijeka uopće nisu slane.

U prosjeku se oceani sastoje od oko 3,5 % soli, što iznosi milijun milijardi tona soli. Ako nakupimo svu tu oceansku sol na kopno, to bi stvorilo sloj visok 152 metra. Dakle, pitanje je – kako je sol dospjela u ocean?

Sol u oceanu dolazi iz dva izvora: otjecanje s kopna i otvori u morskom dnu, prenosi Pomorac.net.

Stijene na kopnu glavni su izvor soli otopljene u morskoj vodi. Kišna voda koja padne na kopno je blago kisela, pa erodira stijene koje zauzvrat oslobađaju ione koji oteku u potoke i rijeke koji na kraju dospiju u ocean. Mnogo otopljenih iona koriste organizmi u oceanu i tim putem nestaju iz vode. Ostatak ostaje pa se koncentracija s vremenom povećava.

Voda u rijekama i jezerima također sadrži sol, ali količina soli u tim vodama je vrlo mala, otprilike 220 puta manja od morske vode, ali je ima i ta se sol taloži u more kad se rijeka ulije u more. Važno je napomenuti da se sol koncentrira u moru jer sunčeva toplina destilira vodu s površine.

Drugi izvor soli u oceanu su hidrotermalne tekućine koje dolaze iz otvora u morskom dnu. Oceanska voda prodire u pukotine u morskom dnu i zagrijava se magmom iz Zemljine jezgre. Toplina uzrokuje niz kemijskih reakcija. Voda gubi kisik, magnezij i sulfate, a iz okolnih stijena skuplja metale poput željeza, cinka i bakra. Zagrijana voda izlazi kroz otvore u morskom dnu, noseći sa sobom metale. Neke oceanske soli potječu od podvodnih vulkanskih erupcija koje izravno oslobađaju minerale u ocean.

Dva najrasprostranjenija iona u morskoj vodi su klorid i natrij. Zajedno čine oko 85 posto svih otopljenih iona u oceanu. Magnezij i sulfat čine još 10 posto ukupnog broja. Ostali ioni poput kalcija nalaze se u vrlo malim koncentracijama, jer živi organizmi poput mekušaca, rakova i koralja koriste ogromne količine kalcija za izgradnju svoje tjelesne strukture. Bez ovog priljeva soli i minerala iz rijeka i potoka život u oceanima bio bi vrlo različit.

Postoje razlike u salinitetu širom svijeta. Prema polovima, morska se voda razrijeđuje otapanjem leda i obilnim oborinama dok na područjima koja graniče s ekvatorom, gdje je vruće, brzina isparavanja premašuje količinu kiše pa je voda ovdje puno slanija.

Također, postoje dokazi koji ukazuju na to da se ove razlike povećavaju kako temperature mora rastu, prenosi Pomorac.net.

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Svi znamo da je morska voda slana, ali jeste li se ikad zapitali zašto? Nije li čudno da je morska (oceanska) voda uvijek slana, a druge vode poput jezera i rijeka uopće nisu slane.

U prosjeku se oceani sastoje od oko 3,5 % soli, što iznosi milijun milijardi tona soli. Ako nakupimo svu tu oceansku sol na kopno, to bi stvorilo sloj visok 152 metra. Dakle, pitanje je – kako je sol dospjela u ocean?

Sol u oceanu dolazi iz dva izvora: otjecanje s kopna i otvori u morskom dnu, prenosi Pomorac.net.

Stijene na kopnu glavni su izvor soli otopljene u morskoj vodi. Kišna voda koja padne na kopno je blago kisela, pa erodira stijene koje zauzvrat oslobađaju ione koji oteku u potoke i rijeke koji na kraju dospiju u ocean. Mnogo otopljenih iona koriste organizmi u oceanu i tim putem nestaju iz vode. Ostatak ostaje pa se koncentracija s vremenom povećava.

Voda u rijekama i jezerima također sadrži sol, ali količina soli u tim vodama je vrlo mala, otprilike 220 puta manja od morske vode, ali je ima i ta se sol taloži u more kad se rijeka ulije u more. Važno je napomenuti da se sol koncentrira u moru jer sunčeva toplina destilira vodu s površine.

Drugi izvor soli u oceanu su hidrotermalne tekućine koje dolaze iz otvora u morskom dnu. Oceanska voda prodire u pukotine u morskom dnu i zagrijava se magmom iz Zemljine jezgre. Toplina uzrokuje niz kemijskih reakcija. Voda gubi kisik, magnezij i sulfate, a iz okolnih stijena skuplja metale poput željeza, cinka i bakra. Zagrijana voda izlazi kroz otvore u morskom dnu, noseći sa sobom metale. Neke oceanske soli potječu od podvodnih vulkanskih erupcija koje izravno oslobađaju minerale u ocean.

Dva najrasprostranjenija iona u morskoj vodi su klorid i natrij. Zajedno čine oko 85 posto svih otopljenih iona u oceanu. Magnezij i sulfat čine još 10 posto ukupnog broja. Ostali ioni poput kalcija nalaze se u vrlo malim koncentracijama, jer živi organizmi poput mekušaca, rakova i koralja koriste ogromne količine kalcija za izgradnju svoje tjelesne strukture. Bez ovog priljeva soli i minerala iz rijeka i potoka život u oceanima bio bi vrlo različit.

Postoje razlike u salinitetu širom svijeta. Prema polovima, morska se voda razrijeđuje otapanjem leda i obilnim oborinama dok na područjima koja graniče s ekvatorom, gdje je vruće, brzina isparavanja premašuje količinu kiše pa je voda ovdje puno slanija.

Također, postoje dokazi koji ukazuju na to da se ove razlike povećavaju kako temperature mora rastu, prenosi Pomorac.net.

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znanstveni kutakSvi znamo da je morska voda slana, no jeste li se ikad zapitali zašto je tomu tako?

Piše OM
17. veljače 2021. - 13:45

Svi znamo da je morska voda slana, ali jeste li se ikad zapitali zašto? Nije li čudno da je morska (oceanska) voda uvijek slana, a druge vode poput jezera i rijeka uopće nisu slane.

U prosjeku se oceani sastoje od oko 3,5 % soli, što iznosi milijun milijardi tona soli. Ako nakupimo svu tu oceansku sol na kopno, to bi stvorilo sloj visok 152 metra. Dakle, pitanje je – kako je sol dospjela u ocean?

Sol u oceanu dolazi iz dva izvora: otjecanje s kopna i otvori u morskom dnu, prenosi Pomorac.net.

Stijene na kopnu glavni su izvor soli otopljene u morskoj vodi. Kišna voda koja padne na kopno je blago kisela, pa erodira stijene koje zauzvrat oslobađaju ione koji oteku u potoke i rijeke koji na kraju dospiju u ocean. Mnogo otopljenih iona koriste organizmi u oceanu i tim putem nestaju iz vode. Ostatak ostaje pa se koncentracija s vremenom povećava.

Voda u rijekama i jezerima također sadrži sol, ali količina soli u tim vodama je vrlo mala, otprilike 220 puta manja od morske vode, ali je ima i ta se sol taloži u more kad se rijeka ulije u more. Važno je napomenuti da se sol koncentrira u moru jer sunčeva toplina destilira vodu s površine.

Drugi izvor soli u oceanu su hidrotermalne tekućine koje dolaze iz otvora u morskom dnu. Oceanska voda prodire u pukotine u morskom dnu i zagrijava se magmom iz Zemljine jezgre. Toplina uzrokuje niz kemijskih reakcija. Voda gubi kisik, magnezij i sulfate, a iz okolnih stijena skuplja metale poput željeza, cinka i bakra. Zagrijana voda izlazi kroz otvore u morskom dnu, noseći sa sobom metale. Neke oceanske soli potječu od podvodnih vulkanskih erupcija koje izravno oslobađaju minerale u ocean.

Dva najrasprostranjenija iona u morskoj vodi su klorid i natrij. Zajedno čine oko 85 posto svih otopljenih iona u oceanu. Magnezij i sulfat čine još 10 posto ukupnog broja. Ostali ioni poput kalcija nalaze se u vrlo malim koncentracijama, jer živi organizmi poput mekušaca, rakova i koralja koriste ogromne količine kalcija za izgradnju svoje tjelesne strukture. Bez ovog priljeva soli i minerala iz rijeka i potoka život u oceanima bio bi vrlo različit.

Postoje razlike u salinitetu širom svijeta. Prema polovima, morska se voda razrijeđuje otapanjem leda i obilnim oborinama dok na područjima koja graniče s ekvatorom, gdje je vruće, brzina isparavanja premašuje količinu kiše pa je voda ovdje puno slanija.

Također, postoje dokazi koji ukazuju na to da se ove razlike povećavaju kako temperature mora rastu, prenosi Pomorac.net.

13. svibanj 2024 21:39