Me\u00f0 n\u00e1tt\u00farulegum uppsprettum er \u00e1tt vi\u00f0 n\u00e1tt\u00farulegt a\u00f0streymi ol\u00edu \u00ed sj\u00f3inn \u00fear sem ol\u00eda kemur upp \u00e1 sj\u00e1varbotni e\u00f0a \u00e1 landi og rennur til sj\u00e1var.<\/p>\n
![\"\"](\"https:\/\/himinnoghaf.is\/mengunsjavar\/wp-content\/uploads\/Mynd2.9-Oliuflekkur.jpg\")
<\/a>Mynd 2.9. Ol\u00eduflekkur \u00e1 sj\u00f3.<\/p><\/div>\n
Undir losun fr\u00e1 sj\u00e1vartengdri starfsemi falla \u00ed fyrsta lagi \u00f3h\u00f6pp vegna ol\u00eduflutningaskipa, annarra skipa, ol\u00eduborpalla og ol\u00edulei\u00f0slna. Tali\u00f0 er a\u00f0 \u00e1 \u00e1ratugnum 1970-1980 hafi a\u00f0 me\u00f0altali 3 millj\u00f3nir tonna af ol\u00edu runni\u00f0 \u00ed sj\u00f3inn \u00e1rlega \u00ed um 25 slysum ol\u00eduflutningaskipa. S\u00ed\u00f0an \u00fe\u00e1 hefur st\u00f3rum \u00f3h\u00f6ppum sem betur fer f\u00e6kka\u00f0 miki\u00f0 og s\u00f6mulei\u00f0is hefur minni ol\u00eda sloppi\u00f0 \u00ed sj\u00f3inn vegna \u00f3happa ol\u00eduflutningaskipa (mynd 2.10), \u00fer\u00e1tt fyrir a\u00f0 ol\u00eduflutningar hafi aukist gr\u00ed\u00f0arlega. \u00cd \u00f6\u00f0ru lagi er um a\u00f0 r\u00e6\u00f0a viljandi losun tengda rekstri skipa, ol\u00eduborpalla og ol\u00edulei\u00f0slna. \u00c1 s\u00ed\u00f0ustu \u00e1ratugum hafa veri\u00f0 settar mun strangari reglur um losun ol\u00edu \u00ed sj\u00f3 vegna sl\u00edkrar starfsemi og eftirlit auki\u00f0. \u00c1 m\u00f3ti kemur a\u00f0 skipaumfer\u00f0 og ol\u00eduvinnsla hefur aukist miki\u00f0. V\u00e6ntanlega hafa hertar reglur skila\u00f0 s\u00e9r \u00ed minni losun, \u00fe\u00f3 a\u00f0 erfitt s\u00e9 a\u00f0 segja til um \u00fea\u00f0 \u00feegar t\u00f6lfr\u00e6\u00f0in er \u00f3n\u00e1kv\u00e6m. \u00cd \u00feri\u00f0ja lagi er um a\u00f0 r\u00e6\u00f0a loftborin mengunarefni (rokgj\u00f6rn l\u00edfr\u00e6n efni, fj\u00f6lhringja ar\u00f3mat\u00edsk kolvetni) sem lenda \u00ed sj\u00f3num.<\/p>\n
<\/a>Mynd 2.10. Fj\u00f6ldi st\u00f3rra og me\u00f0alst\u00f3rra ol\u00eduslysa af v\u00f6ldum ol\u00eduflutningaskipa fr\u00e1 1970 til 2022 (vinstra megin) og magn ol\u00edu sem lenti \u00ed sj\u00f3num \u00e1 sama t\u00edmabili (h\u00e6gra megin).<\/p><\/div>\n
Undir losun fr\u00e1 starfsemi \u00ed landi fellur afrennsli me\u00f0 \u00e1m og \u00far sk\u00f3lplei\u00f0slum, losun vegna \u00f3me\u00f0h\u00f6ndla\u00f0s e\u00f0a \u00f3fulln\u00e6gjandi me\u00f0h\u00f6ndla\u00f0s affallsvatns fr\u00e1 i\u00f0na\u00f0i vi\u00f0 str\u00f6nd og losun vegna slysa og hef\u00f0bundins rekstrar ol\u00eduhreinsist\u00f6\u00f0va og ol\u00edubirg\u00f0ast\u00f6\u00f0va. \u00de\u00e1 falla loftborin mengunarefni fr\u00e1 landi \u00ed sj\u00f3inn vegna ol\u00edume\u00f0h\u00f6ndlunar og ol\u00edubrennslu (b\u00edlaumfer\u00f0). Reglur var\u00f0andi losun fr\u00e1 starfsemi \u00ed landi hafa veri\u00f0 hertar miki\u00f0 s\u00ed\u00f0ustu \u00e1r og \u00e1ratugi.<\/p>\n
2.8.1 Ve\u00f0run og afdrif ol\u00edu \u00ed sj\u00f3<\/h5>\n
Hluti ol\u00edunnar \u00ed sj\u00f3num kemur fr\u00e1 n\u00e1tt\u00farulegum uppsprettum annars vegar og dreif\u00f0um uppsprettum hins vegar. S\u00fa mengun dreifist alla jafna yfir st\u00f3rt sv\u00e6\u00f0i og langan t\u00edma og veldur \u00fev\u00ed ekki eins afgerandi \u00e1hrifum og ol\u00edumengun sem rekja m\u00e1 til slysa.<\/p>\n
\u00deegar ol\u00eda lendir \u00ed sj\u00f3 fara af sta\u00f0 \u00fdmis ferli sem stu\u00f0la a\u00f0 dreifingu og ni\u00f0urbroti ol\u00edunnar. D\u00e6mi um \u00feetta eru \u00fatbrei\u00f0sla, uppgufun, dreifing, myndun kvo\u00f0ulausnar, uppleysing, lj\u00f3sni\u00f0urbrot og l\u00edfr\u00e6nt ni\u00f0urbrot. V\u00e6gi hvers ferlis er breytilegt eftir t\u00edma, tegund ol\u00edu og fleiri \u00fe\u00e1ttum. Sko\u00f0um n\u00fa afdrif ol\u00eduflekks sem lent hefur \u00ed sj\u00f3num vegna slyss.<\/p>\n
<\/a>Mynd 2.11. Afdrif ol\u00eduflekks \u00ed sj\u00f3.<\/p><\/div>\n
<\/span><\/strong><\/em>\u00datbrei\u00f0sla<\/strong><\/em><\/h6>\nOl\u00eda byrjar a\u00f0 brei\u00f0ast \u00fat \u00e1 yfirbor\u00f0i sj\u00e1var um lei\u00f0 og h\u00fan lendir \u00ed sj\u00f3num. Hversu hratt \u00fea\u00f0 gerist fer eftir magni ol\u00edunnar og seigju hennar. Ol\u00eda me\u00f0 litla seigju brei\u00f0ist mun hra\u00f0ar \u00fat en ol\u00eda me\u00f0 mikla seigju. Til a\u00f0 byrja me\u00f0 brei\u00f0ist ol\u00edan \u00fat sem samfelldur flekkur en brotnar flj\u00f3tlega upp. S\u00e1 hluti ol\u00edunnar sem er n\u00e1nast fast efni (\u00feyngstu eimingarefnin og tj\u00f6ruhlutinn) e\u00f0a v\u00f6kvi me\u00f0 mikla seigju brotnar \u00ed b\u00fata e\u00f0a hluta sem f\u00e6rast \u00ed sundur. \u00deessir b\u00fatar geta veri\u00f0 nokkrir cm \u00e1 \u00feykkt. Hra\u00f0i \u00fatbrei\u00f0slunnar er h\u00e1\u00f0ur \u00f6ldugangi og hafstraumum. Mikill \u00f6ldugangur og sterkir straumar lei\u00f0a til hra\u00f0ari \u00fatbrei\u00f0slu.<\/p>\n
<\/span><\/strong><\/em>Uppgufun<\/strong><\/em><\/h6>\nRokgjarnasti hluti ol\u00edunnar gufar upp \u00ed andr\u00famslofti\u00f0, en hra\u00f0i uppgufunar er h\u00e1\u00f0ur lofthita og vindhra\u00f0a. Uppgufunin er hra\u00f0ari eftir \u00fev\u00ed sem ol\u00edan hefur h\u00e6rra hlutfall af eimingarefnum me\u00f0 l\u00e1gt su\u00f0umark. Almennt m\u00e1 segja a\u00f0 \u00feeir hlutar ol\u00edunnar sem hafa l\u00e6gra su\u00f0umark en 200\u00b0C gufi upp innan s\u00f3larhrings vi\u00f0 tempra\u00f0ar ve\u00f0ura\u00f0st\u00e6\u00f0ur. Eins og sj\u00e1 m\u00e1 \u00e1 mynd 2.8 er t.d. um 60% hr\u00e1ol\u00edunnar \u00ed flokki 1 me\u00f0 su\u00f0umark undir 200\u00b0C en \u00feetta hlutfall er a\u00f0eins um 5% hj\u00e1 hr\u00e1ol\u00edunni \u00ed flokki 4. \u00dev\u00ed st\u00e6rra sem yfirbor\u00f0sflatarm\u00e1l ol\u00eduflekksins er, \u00fev\u00ed meiri ver\u00f0ur uppgufun l\u00e9ttu eimingarefnanna. Hra\u00f0i \u00fatbrei\u00f0slu ol\u00edunnar fyrst eftir \u00f3happi\u00f0 hefur \u00fev\u00ed einnig \u00e1hrif \u00e1 uppgufunina. \u00d6ldugangur, mikill vindur og h\u00e1r loft- og sj\u00e1varhiti eykur einnig uppgufun. \u00de\u00e6r ol\u00eduleifar sem eftir ver\u00f0a \u00feegar uppgufun hefur \u00e1tt s\u00e9r sta\u00f0, hafa meiri e\u00f0lis\u00feyngd og meiri seigju. \u00deessir \u00fe\u00e6ttir hafa \u00e1hrif \u00e1 frekari ve\u00f0run ol\u00edunnar sem og hva\u00f0a a\u00f0fer\u00f0ir h\u00e6gt er a\u00f0 beita vi\u00f0 hreinsun.<\/p>\n
Ol\u00eduflekkur \u00far unnum ol\u00eduv\u00f6rum (t.d. steinol\u00edu e\u00f0a bens\u00edni) getur gufa\u00f0 algj\u00f6rlega upp \u00e1 nokkrum klukkut\u00edmum. L\u00e9ttar hr\u00e1ol\u00edur geta minnka\u00f0 um helming a\u00f0 umfangi \u00e1 fyrsta s\u00f3larhringnum. \u00deegar \u00f3h\u00f6pp ver\u00f0a \u00e1 loku\u00f0um sv\u00e6\u00f0um me\u00f0 svona rokgjarnar ol\u00edur er eld- og\/e\u00f0a sprengih\u00e6ttan mikil, auk \u00feess sem heilsu f\u00f3lks getur stafa\u00f0 h\u00e6tta af. L\u00edtil sprengih\u00e6tta er af v\u00f6ldum \u00feungra ol\u00eduefna. Hins vegar getur eldh\u00e6tta stafa\u00f0 af \u00feeim, t.d. ef eldur kemur upp \u00ed rusli sem g\u00e6ti veri\u00f0 til sta\u00f0ar \u00ed ol\u00eduflekknum.<\/p>\n
<\/span><\/strong><\/em>Dreifing<\/strong><\/em><\/h6>\nHra\u00f0i dreifingar er a\u00f0allega h\u00e1\u00f0ur e\u00f0liseiginleikum ol\u00edunnar og a\u00f0st\u00e6\u00f0um \u00e1 sj\u00f3. Hra\u00f0ast dreifist l\u00e1gseigju-ol\u00eda \u00ed brotsj\u00f3. \u00d6ldur og i\u00f0ustraumar vi\u00f0 yfirbor\u00f0 sj\u00e1var geta valdi\u00f0 \u00fev\u00ed a\u00f0 hluti e\u00f0a allur flekkurinn brotni upp \u00ed dropa af mismunandi st\u00e6r\u00f0um, sem s\u00ed\u00f0an blandast vi\u00f0 efri l\u00f6g sj\u00e1varins. Litlir dropar haldast \u00ed upplausn en st\u00e6rri droparnir flj\u00f3ta upp \u00e1 yfirbor\u00f0 \u00fear sem \u00feeir anna\u00f0 hvort blandast \u00f6\u00f0rum dropum og endurmynda flekkinn e\u00f0a brei\u00f0ast \u00fat eins og \u00feunn filma. Ol\u00eda me\u00f0 mikla seigju hefur litla tilhneigingu til a\u00f0 dreifast.<\/p>\n
<\/span><\/strong><\/em>Myndun kvo\u00f0ulausnar<\/strong><\/em><\/h6>\nM\u00f6rg ol\u00eduefni taka upp vatn og mynda kvo\u00f0ulausn \u00fear sem vatn er \u00ed ol\u00edudropunum. \u00deetta ferli getur auki\u00f0 r\u00famm\u00e1l mengunarflekksins allt a\u00f0 fimmfalt. Ol\u00edur sem innihalda nikkel og\/e\u00f0a vanad\u00edum \u00ed meira magni en 15 ppm<\/span> e\u00f0a asfalten \u00ed meira magni en 0,5% mynda kvo\u00f0ulausn frekar en a\u00f0rar. Hra\u00f0i kvo\u00f0umyndunar er h\u00e1\u00f0ur vindhra\u00f0a \u2013 \u00fev\u00ed meiri sem vindurinn er \u00fev\u00ed hra\u00f0ar myndast kvo\u00f0an. Ol\u00edur me\u00f0 mikla seigju taka vatn s\u00ed\u00f0ur upp en ol\u00edur me\u00f0 l\u00e6gri seigju. Me\u00f0 t\u00edmanum, \u00feegar ol\u00edan hreyfist me\u00f0 \u00f6ldum, minnka vatnsdroparnir inni \u00ed ol\u00edudropunum og kvo\u00f0an ver\u00f0ur seigari. \u00c1 sama t\u00edma falla tj\u00f6ruefni \u00fat \u00far ol\u00edunni og mynda einskonar h\u00fa\u00f0 utan um vatnsdropana. \u00deetta eykur st\u00f6\u00f0ugleika kvo\u00f0ulausnarinnar. St\u00f6\u00f0ug kvo\u00f0ulausn getur innihaldi\u00f0 70-80% vatn (sj\u00f3) og er oft h\u00e1lfpartinn eins og fast efni. Liturinn \u00e1 \u201e\u00feroska\u00f0ri\u201c kvo\u00f0ulausn er rau\u00f0br\u00fann e\u00f0a jafnvel \u00fat \u00ed appels\u00ednugult. Sl\u00edk kvo\u00f0ulausn er afar \u00fer\u00e1virk<\/span> og getur vi\u00f0haldist \u00ed mj\u00f6g langan t\u00edma. \u00d3st\u00f6\u00f0ugri kvo\u00f0ulausnir skiljast \u00ed sundur \u00ed ol\u00edu og vatn ef \u00fe\u00e6r hitna fyrir tilstilli s\u00f3larlj\u00f3ss \u00ed l\u00e1dau\u00f0um sj\u00f3 e\u00f0a \u00feegar \u00fe\u00e6r berast \u00e1 str\u00f6nd, ef \u00fea\u00f0 \u00e1 anna\u00f0 bor\u00f0 gerist.<\/p>\nMyndun kvo\u00f0ulausnar dregur \u00far \u00e1hrifum annarrar ve\u00f0runar og er helsta \u00e1st\u00e6\u00f0a \u00feess a\u00f0 l\u00e9tt og me\u00f0al\u00feung hr\u00e1ol\u00eda ver\u00f0ur \u00fer\u00e1virk \u00e1 yfirbor\u00f0i sj\u00e1var e\u00f0a vi\u00f0 strendur.<\/p>\n
![\"\"](\"https:\/\/himinnoghaf.is\/mengunsjavar\/wp-content\/uploads\/Mynd2.12-Kvodulausn_v3.jpg\")
<\/a>Mynd 2.12. Til vinstri m\u00e1 sj\u00e1 kvo\u00f0ulausn \u00e1 r\u00famsj\u00f3 og \u00ed mi\u00f0junni kvo\u00f0ulausn vi\u00f0 str\u00f6nd. \u00c1 myndinni lengst til h\u00e6gri m\u00e1 sj\u00e1 hvernig h\u00e1lfstorkna\u00f0ir ol\u00eduflekkir hafa myndast \u00fear sem ol\u00eda hefur lent \u00ed sj\u00f3 sem er kaldari en rennslismark ol\u00edunnar. \u00cd \u00feessu tilfelli er um a\u00f0 r\u00e6\u00f0a hr\u00e1ol\u00edu me\u00f0 rennslismark 33\u00b0C og sj\u00f3 vi\u00f0 28\u00b0C.<\/p><\/div>\n
<\/span><\/strong><\/em>Uppleysing<\/strong><\/em><\/h6>\nHra\u00f0i og umfang uppleysingar ol\u00edu \u00ed sj\u00f3 er h\u00e1\u00f0 samsetningu ol\u00edunnar, \u00fatbrei\u00f0slu, sj\u00e1varhita, i\u00f0ustraumum<\/span> og umfangi dreifingar. \u00deyngri eimingarhlutar hr\u00e1ol\u00edu eru n\u00e1nast \u00f3leysanlegir \u00ed vatni. L\u00e9ttari eimingarhlutarnir, s\u00e9r \u00ed lagi ar\u00f3mat\u00edsk vetniskolefni eins og bensen og t\u00f3l\u00faen, leysast hins vegar upp a\u00f0 vissu marki. \u00c1 sama t\u00edma eru \u00feetta rokgj\u00f6rnustu efnin og gufa yfirleitt upp um 10 til 1000 sinnum hra\u00f0ar en \u00feau leysast upp. Styrkur \u00feeirra \u00ed sj\u00f3 er \u00fev\u00ed yfirleitt minni en 1 ppm. Uppleysing \u00e1 \u00fev\u00ed ekki st\u00f3ran \u00fe\u00e1tt \u00ed a\u00f0 fjarl\u00e6gja ol\u00edu af sj\u00e1varyfirbor\u00f0i.<\/p>\n<\/span><\/strong><\/em>Lj\u00f3sni\u00f0urbrot<\/strong><\/em><\/h6>\nOl\u00eda er ger\u00f0 \u00far vetniskolefnum og vetniskolefni geta hvarfast vi\u00f0 s\u00farefni (oxun). Sl\u00edk efnahv\u00f6rf geta leitt annars vegar til myndunar \u00e1 uppleysanlegum efnum og hins vegar \u00e1 \u00fer\u00e1virkum tj\u00f6ruefnum. S\u00f3larlj\u00f3s \u00fdtir undir oxun en jafnvel \u00fe\u00f3tt s\u00f3lar nj\u00f3ti vi\u00f0 eru heildar\u00e1hrif lj\u00f3sni\u00f0urbrots l\u00edtil \u00ed ve\u00f0runarferlinu. \u00deykk l\u00f6g af mj\u00f6g seigri ol\u00edu, e\u00f0a ol\u00edukvo\u00f0u oxast frekar \u00ed \u00fer\u00e1virkar leifar en brotna l\u00edti\u00f0 ni\u00f0ur. \u00deetta stafar af \u00fev\u00ed a\u00f0 \u00ed ferlinu ver\u00f0a til \u00feung efnasamb\u00f6nd\u00a0 sem mynda verndandi yfirbor\u00f0slag (\u00fe.e. yfirbor\u00f0slag sem verndar ol\u00eduflekkinn fyrir frekara ni\u00f0urbroti).<\/p>\n
<\/span><\/strong><\/em>Setmyndun og botnfall<\/strong><\/em><\/h6>\nOl\u00edudropar sem dreif\u00f0ir eru \u00ed sj\u00f3num geta sest \u00e1 svifagnir og l\u00edfr\u00e6nt efni \u00ed upplausn \u00ed sj\u00f3num og \u00feannig or\u00f0i\u00f0 n\u00e6gilega e\u00f0lis\u00feungir til a\u00f0 s\u00f6kkva til botns. Magn sl\u00edkra svifagna er oft miki\u00f0 \u00e1 grunns\u00e6vi og vi\u00f0 \u00e1r\u00f3sa\u00a0 og \u00fear myndast \u00fev\u00ed kj\u00f6ra\u00f0st\u00e6\u00f0ur fyrir setmyndun ol\u00edukenndra agna. Pl\u00f6ntu- og d\u00fdrasvif geta teki\u00f0 ol\u00eduna upp. \u00deannig getur ol\u00edan enda\u00f0 sem hluti af \u00fargangsefnum svifsins og sokki\u00f0 me\u00f0 \u00feeim til botns. Vindborinn sandur e\u00f0a aska getur einnig sest \u00e1 ol\u00edudropa og valdi\u00f0 setmyndun.<\/p>\n
Flestar ol\u00edur eru n\u00e6gjanlega e\u00f0lisl\u00e9ttar til a\u00f0 flj\u00f3ta \u00e1 vatni nema \u00fe\u00e6r ver\u00f0i fyrir \u00e1hrifum \u00feyngri agna. Sumar ol\u00edur, \u00feungar hr\u00e1ol\u00edur, \u00feungar eldsneytisol\u00edur og ol\u00edukvo\u00f0ur hafa e\u00f0lis\u00feyngd sem er n\u00e1l\u00e6gt e\u00f0lis\u00feyngd sj\u00e1var, \u00feannig a\u00f0 l\u00edti\u00f0 \u00fearf af set\u00f6gnum e\u00f0a \u00e1foki til a\u00f0 \u00fe\u00e6r botnfalli. \u00d6rf\u00e1ar \u00feungaol\u00edur hafa meiri e\u00f0lis\u00feyngd en sj\u00f3r og \u00fe\u00e6r botnfalla. Sumar ol\u00edur geta sokki\u00f0 til botns eftir \u00edkveikju, \u00fear sem eldurinn brennir l\u00e9ttari efnunum \u00e1 sama t\u00edma og \u00feung efni myndast vegna hitans.<\/p>\n
\u00cd \u00f3lgusj\u00f3 getur lag af vatni fl\u00e6tt yfir e\u00f0lis\u00feunga ol\u00edu. Vi\u00f0komandi ol\u00eduflekkur getur \u00fe\u00e1 veri\u00f0 \u00ed talsver\u00f0an t\u00edma fyrir ne\u00f0an sj\u00e1varm\u00e1l og \u00fev\u00ed erfitt a\u00f0 finna hann. \u00deegar ve\u00f0ur l\u00e6gir og \u00f6ldugangur minnkar fl\u00fdtur flekkurinn aftur upp \u00e1 yfirbor\u00f0.<\/p>\n
Botnfall ol\u00edumenga\u00f0s sets er ein helsta \u00e1st\u00e6\u00f0a \u00feess a\u00f0 ol\u00edumengun safnast fyrir \u00ed l\u00edfr\u00edki sj\u00e1var. Mj\u00f6g f\u00e1t\u00edtt er a\u00f0 setmyndun eigi s\u00e9r sta\u00f0 annars sta\u00f0ar en \u00e1 grunns\u00e6vi n\u00e1l\u00e6gt str\u00f6nd, og \u00fe\u00e1 a\u00f0allega vegna v\u00edxlverkunar vi\u00f0 strandlengjuna og setagnir sem berast fr\u00e1 henni.<\/p>\n
<\/span><\/strong><\/em>L\u00edfr\u00e6nt ni\u00f0urbrot<\/strong><\/em><\/h6>\n\u00cd sj\u00f3num lifa \u00f6rverur sem geta n\u00fdtt s\u00e9r ol\u00edu til vaxtar og vi\u00f0halds. H\u00e9r er um a\u00f0 r\u00e6\u00f0a bakter\u00edur, sveppi, \u00fe\u00f6runga og frumd\u00fdr, sem n\u00fdtt geta ol\u00edu sem kolefnis- og orkugjafa. Sl\u00edkar l\u00edfverur er a\u00f0 finna um heimsh\u00f6fin en \u00fe\u00e6r eru algengari \u00fear sem n\u00e1tt\u00farlegt a\u00f0streymi ol\u00edu \u00e1 s\u00e9r sta\u00f0 og \u00e1 strandsv\u00e6\u00f0um \u00fear sem st\u00f6\u00f0uga ol\u00edumengun er a\u00f0 finna. Eiginleikar ol\u00edunnar, hitastig og frambo\u00f0 s\u00farefnis og n\u00e6ringarefna (N og P) hafa \u00e1hrif \u00e1 hra\u00f0a og umfang l\u00edfr\u00e6ns ni\u00f0urbrots. Hver \u00f6rverutegund br\u00fdtur yfirleitt ni\u00f0ur \u00e1kve\u00f0in vetniskolefni, \u00feannig a\u00f0 fyrir \u00e1framhaldandi ni\u00f0urbrot \u00fearf margar tegundir \u00f6rvera sem vinna saman e\u00f0a hver \u00e1 eftir annarri. \u00dati \u00e1 r\u00famsj\u00f3 er yfirleitt l\u00edti\u00f0 um \u00fe\u00e6r \u00f6rverur sem \u00fearf \u00ed l\u00edfni\u00f0urbroti\u00f0, en \u00feeim fj\u00f6lgar \u00fe\u00f3 tilt\u00f6lulega hratt \u00feegar ol\u00eda er til sta\u00f0ar. Ni\u00f0urbrot \u00e1 s\u00e9r \u00fe\u00e1 sta\u00f0 \u00fear til skortur ver\u00f0ur \u00e1 s\u00farefni e\u00f0a n\u00e6ringarefnum. \u00de\u00f3 a\u00f0 \u00f6rverur geti broti\u00f0 ni\u00f0ur m\u00f6rg \u00feeirra sambanda sem er a\u00f0 finna \u00ed hr\u00e1ol\u00edu, eru st\u00e6rstu og fl\u00f3knustu sameindirnar illni\u00f0urbrj\u00f3tanlegar.<\/p>\n
\u00dear sem \u00f6rverurnar \u00feurfa n\u00e6ringarefni og s\u00farefni til a\u00f0 geta n\u00fdtt s\u00e9r ol\u00eduefnin, \u00e1 l\u00edfr\u00e6nt ni\u00f0urbrot s\u00e9r einungis sta\u00f0 \u00ed yfirbor\u00f0slagi sj\u00e1var. Vi\u00f0 myndun ol\u00edudropa \u00fati \u00e1 r\u00famsj\u00f3 st\u00e6kkar yfirbor\u00f0i\u00f0 sem \u00f6rverurnar geta athafna\u00f0 sig \u00e1 og \u00fev\u00ed eykst ni\u00f0urbroti\u00f0. \u00c1 hinn b\u00f3ginn hefur \u00feykkt ol\u00edulag vi\u00f0 strandlengjuna e\u00f0a fyrir ofan h\u00e1fj\u00f6ru takmarka\u00f0 yfirbor\u00f0 og takmarka\u00f0a snertingu vi\u00f0 vatn. Vi\u00f0 sl\u00edkar a\u00f0st\u00e6\u00f0ur ver\u00f0ur l\u00edfni\u00f0urbrot mj\u00f6g h\u00e6gt, \u00feannig a\u00f0 ol\u00edan getur veri\u00f0 til sta\u00f0ar \u00ed \u00e1ratugi s\u00e9 h\u00fan ekki fjarl\u00e6g\u00f0.<\/p>\n
\u00dear sem margir \u00fe\u00e6ttir hafa \u00e1hrif \u00e1 l\u00edfni\u00f0urbrot er erfitt a\u00f0 sp\u00e1 fyrir um hversu miklu \u00fea\u00f0 skilar vi\u00f0 ni\u00f0urbrot \u00e1 ol\u00edu. L\u00edfni\u00f0urbrot getur ekki eytt ol\u00edu \u00ed miklu magni, en er til langs t\u00edma ein helsta lei\u00f0in fyrir n\u00e1tt\u00farlega ey\u00f0ingu \u00e1 s\u00ed\u00f0ustu leifum ol\u00edu af strandlengjunni.<\/p>\n
<\/span><\/strong><\/em>Samtvinnun mismunandi ve\u00f0runarferla<\/strong><\/em><\/h6>\n\u00deeir ferlar sem h\u00e9r hafa veri\u00f0 nefndir fara allir \u00ed gang \u00feegar ol\u00eduslys eiga s\u00e9r sta\u00f0, \u00fe\u00f3 a\u00f0 hlutfallslegt v\u00e6gi \u00feeirra s\u00e9 breytilegt eftir \u00fev\u00ed sem t\u00edmanum vindur fram. \u00datbrei\u00f0sla, uppgufun, dreifing, myndun kvo\u00f0ulausnar og uppleysing skipta mestu m\u00e1li stuttu eftir slys. Lj\u00f3sni\u00f0urbrot, setmyndun og l\u00edfni\u00f0urbrot eru hins vegar \u00feeir ferlar sem r\u00e1\u00f0a mestu um endanleg afdrif ol\u00eduflekksins. Dreifing annars vegar og myndun kvo\u00f0ulausnar hins vegar hafa mj\u00f6g \u00f3l\u00edk \u00e1hrif \u00e1 afdrif ol\u00eduflekkja \u00fear sem dreifing flytur ol\u00edu fr\u00e1 yfirbor\u00f0i sj\u00e1var og minnkar \u00fev\u00ed ol\u00eduflekkinn en myndun kvo\u00f0ulausnar eykur umfang hans og \u00fer\u00e1virkni mengunarinnar. \u00deeir \u00fe\u00e6ttir sem hafa \u00e1hrif \u00e1 hvort ol\u00eda dreifist e\u00f0a myndi kvo\u00f0ulausn eru m.a:<\/p>\n
\n- a\u00f0st\u00e6\u00f0ur vi\u00f0 slys (hra\u00f0i og magn ol\u00edu sem sleppur \u00fat \u00ed umhverfi\u00f0, hvort ol\u00edan s\u00e9 losu\u00f0 \u00ed yfirbor\u00f0slag e\u00f0a \u00e1 d\u00fdpi, o.fl.),<\/li>\n
- umhverfisa\u00f0st\u00e6\u00f0ur (hitastig, \u00e1stand sj\u00e1var, straumar, o.fl.) og<\/li>\n
- e\u00f0lis- og efnafr\u00e6\u00f0ilegir eiginleikar ol\u00edunnar.<\/li>\n<\/ul>\n
Mikilv\u00e6gt er a\u00f0 skilja v\u00edxlverkun mismunandi ve\u00f0runarferla til a\u00f0 h\u00e6gt s\u00e9 a\u00f0 sj\u00e1 fyrir hvernig best er a\u00f0 breg\u00f0ast vi\u00f0 ol\u00eduleka.<\/p>\n
2.8.2 \u00c1hrif ol\u00edu \u00e1 l\u00edfr\u00edki<\/h5>\n
Ol\u00eda inniheldur sem fyrr segir m\u00f6rg efnasamb\u00f6nd og eru sum \u00feeirra ska\u00f0leg jafnvel \u00ed litlu magni en \u00f6nnur ekki. Fj\u00f6lhringja ar\u00f3mat\u00edsk vetniskolefni (PAH-efni) eru d\u00e6mi um eitru\u00f0 innihaldsefni ol\u00edu, en \u00feau geta m.a. valdi\u00f0 st\u00f6kkbreytingum og krabbameini \u00ed m\u00f6nnum og d\u00fdrum (sj\u00e1 n\u00e1nari umfj\u00f6llun um PAH \u00ed kafla 5.4<\/a>). Hr\u00e1ol\u00eda, en einnig borv\u00f6kvar og dj\u00fapvatn, geta innihaldi\u00f0 \u00fdmsa eitra\u00f0a m\u00e1lma, svo sem kvikasilfur, bl\u00fd, arsen og kadm\u00edum (sj\u00e1 n\u00e1nari umfj\u00f6llun um \u00feungm\u00e1lma \u00ed kafla 5.3<\/a>). \u00deessir m\u00e1lmar hafa fundist \u00ed h\u00e1um styrk \u00ed seti \u00fear sem ol\u00eduslys hafa or\u00f0i\u00f0. Efnasamb\u00f6nd \u00e1 bor\u00f0 vi\u00f0 PAH og \u00feungm\u00e1lma eru \u00fer\u00e1virk og geta \u00fev\u00ed safnast fyrir \u00ed l\u00edfverum. Ol\u00eduefni geta \u00feannig haft eitur\u00e1hrif \u00e1 l\u00edfr\u00edki hafsins, spillt b\u00fasv\u00e6\u00f0um, skemmt sj\u00e1varfang og dregi\u00f0 verulega \u00far \u00fativistargildi strandsv\u00e6\u00f0a.<\/p>\nSem fyrr segir leysast l\u00e9ttar og \u00feunnflj\u00f3tandi ol\u00edur \u00e1 bor\u00f0 vi\u00f0 bens\u00edn og d\u00edsilol\u00edu betur upp \u00ed vatni en \u00feyngri ol\u00edur (svartol\u00eda, hr\u00e1ol\u00eda), \u00fe\u00f3 a\u00f0 l\u00edklegra s\u00e9 a\u00f0 \u00feessi efni gufi upp. L\u00e9ttari ol\u00edurnar eiga fyrir viki\u00f0 mun grei\u00f0ari a\u00f0gang inn \u00ed l\u00edfr\u00edki\u00f0 og geta \u00feannig valdi\u00f0 miklum eitur\u00e1hrifum. Ar\u00f3mat\u00edski<\/span> hluti ol\u00edunnar sker\u00f0ir til a\u00f0 mynda virkni frumuhimna og hefur sl\u00e6m \u00e1hrif \u00e1 frj\u00f3semi hryggleysingja. Einnig hefur veri\u00f0 sta\u00f0fest a\u00f0 \u00fdmis ol\u00eduefni hafa \u00e1hrif \u00e1 \u00fer\u00f3un hrogna og lirfa og h\u00e6fni \u00feeirra til a\u00f0 lifa af. \u00deyngri og seigari ol\u00eda blandast vatnsmassanum mun verr. H\u00fan fl\u00fdtur ofan \u00e1 og \u00ed efstu l\u00f6gum sj\u00e1var og veldur mikilli yfirbor\u00f0smengun vi\u00f0 strendur. Ol\u00edan leggst \u00e1 spend\u00fdr, fugla, skelfisk, fj\u00f6rugr\u00f3\u00f0ur, \u00feara og l\u00edfr\u00edki\u00f0 almennt.<\/p>\n![\"\"](\"https:\/\/himinnoghaf.is\/mengunsjavar\/wp-content\/uploads\/02.7-M2.13-SkjaldbakaogHofrungur.jpg\")
<\/a>Mynd 2.13. Ol\u00edumengu\u00f0 skjaldbaka og h\u00f6frungur eftir slysi\u00f0 \u00ed Mex\u00edk\u00f3fl\u00f3a 2010.<\/p><\/div>\n
Ol\u00eda hefur einna mest \u00e1hrif \u00e1 sj\u00f3fugla. Fuglar \u00feurfa a\u00f0 vi\u00f0halda h\u00e1um og st\u00f6\u00f0ugum l\u00edkamshita. \u00deegar ol\u00eda kl\u00edstrast \u00e1 fja\u00f0rir \u00feeirra skemmast \u00fe\u00e6r og h\u00e6tta a\u00f0 vera vatnsheldar. \u00dear me\u00f0 minnkar einangrunin og fuglunum ver\u00f0ur kalt. Ol\u00edan \u00feyngir auk \u00feess fuglana og torveldar \u00feeim \u00feannig sund og f\u00e6\u00f0u\u00f6flun. S\u00e9 mengunin mikil ver\u00f0a fuglarnir \u00e1 endanum svo \u00feungir a\u00f0 \u00feeir n\u00e1 ekki til lands og s\u00f6kkva \u00fear af lei\u00f0andi og drukkna. \u00de\u00e1 geta fuglar innbyrt eiturefni \u00feegar \u00feeir reyna a\u00f0 hreinsa fja\u00f0rirnar me\u00f0 goggnum.<\/p>\n
![\"\"](\"https:\/\/himinnoghaf.is\/mengunsjavar\/wp-content\/uploads\/02.7-M2.14-DyrIOliu.jpg\")
<\/a>Mynd 2.14. Ol\u00edumenga\u00f0ir fuglar.<\/p><\/div>\n
Sem fyrr segir getur hluti ol\u00edunnar enda\u00f0 \u00e1 botninum, \u00fear sem h\u00fan getur haft umtalsver\u00f0 \u00e1hrif \u00e1 botnd\u00fdral\u00edf, b\u00e6\u00f0i vegna eitur\u00e1hrifa og vegna k\u00e6fingar. Kem\u00edsk efni sem hafa veri\u00f0 notu\u00f0 til a\u00f0 f\u00e1st vi\u00f0 ol\u00eduflekki (sj\u00e1 kafla 2.9<\/a>) geta einnig borist me\u00f0 ol\u00edunni til botns og sum \u00feessara efna eru eitru\u00f0. F\u00e6st botnd\u00fdr hafa mikla hreyfigetu og geta \u00fev\u00ed sjaldnast f\u00e6rt sig fr\u00e1 mengu\u00f0um sv\u00e6\u00f0um eins og t.d. fiskar og spend\u00fdr geta oft gert. Sumar fisktegundir n\u00e6rast \u00e1 botnd\u00fdrum og r\u00f3ta \u00ed botnseti og geta \u00feannig fengi\u00f0 \u00ed sig mengunarefni fr\u00e1 hafsbotni. Botngr\u00f3\u00f0ur er au\u00f0vita\u00f0 botnfastur og ver\u00f0ur \u00fev\u00ed a\u00f0 taka \u00fev\u00ed sem til hans berst.<\/p>\n![\"\"](\"https:\/\/himinnoghaf.is\/mengunsjavar\/wp-content\/uploads\/Mynd2.15-KorallarOliumengadir.jpg\")
<\/a>Mynd 2.15. K\u00f3rallar, n\u00e6r al\u00feaknir br\u00fanu efni sem inniheldur ol\u00edudropa eftir slysi\u00f0 \u00ed Mex\u00edk\u00f3fl\u00f3a 2010, en \u00fear voru kem\u00edsk efni notu\u00f0 til a\u00f0 f\u00e1st vi\u00f0 ol\u00eduflekkinn.<\/p><\/div>\n
Ol\u00edumengun hefur mismunandi \u00e1hrif \u00e1 sj\u00e1varfang. \u00de\u00e6r sj\u00e1varl\u00edfverur sem vi\u00f0 neytum eru mishreyfanlegar og ver\u00f0a fyrir mismikilli mengun. Fiskar geta synt fr\u00e1 mengu\u00f0um st\u00f6\u00f0um og eru \u00fev\u00ed \u00f3l\u00edklegri til a\u00f0 komast \u00ed snertingu vi\u00f0 flj\u00f3tandi ol\u00edu. \u00deeir geta hins vegar or\u00f0i\u00f0 fyrir \u00e1hrifum uppleystrar ol\u00edu e\u00f0a ol\u00edu sem dreifist \u00ed sj\u00f3num. Eins geta fiskar or\u00f0i\u00f0 fyrir \u00e1hrifum ef b\u00fasv\u00e6\u00f0i mengast. Fiskar taka frekar upp sm\u00e6rri PAH-efni en \u00feau st\u00e6rri. St\u00e6rri PAH-efni eru eitra\u00f0ri og geta valdi\u00f0 krabbameini. PAH-efnin skiljast a\u00f0 mestu leyti \u00far holdi fiska (fiskifl\u00f6kunum) en geta safnast fyrir \u00ed lifur og gallbl\u00f6\u00f0ru. Krabbad\u00fdr eru tilt\u00f6lulega l\u00edti\u00f0 hreyfanleg, en geta \u00fe\u00f3 oft f\u00e6rt sig fr\u00e1 ol\u00edumengu\u00f0um sv\u00e6\u00f0um. B\u00fasv\u00e6\u00f0i krabbad\u00fdra og sta\u00f0ir sem \u00feau n\u00e6ra sig \u00e1 geta einnig veri\u00f0 menga\u00f0ir. \u00dea\u00f0 \u00e1 s\u00e9rstaklega vi\u00f0 um tegundir sem grafa sig ofan \u00ed botnset. L\u00edkt og fiskar taka krabbad\u00fdr upp sm\u00e6rri PAH-efni, en \u00feau skiljast hins vegar ekki eins vel fr\u00e1 holdinu og \u00ed fiskum. Lind\u00fdr \u00e1 bor\u00f0 vi\u00f0 ostrur, kr\u00e6klinga og samlokur eru n\u00e1nast \u00f3hreyfanleg og geta ekki f\u00e6rt sig fr\u00e1 mengu\u00f0um sv\u00e6\u00f0um, en ol\u00eduefni og \u00f6nnur efni safnast einmitt oft fyrir \u00e1 b\u00fasv\u00e6\u00f0um \u00feeirra. L\u00edfr\u00e6n mengunarefni safnast i\u00f0ulega fyrir \u00ed lind\u00fdrum.<\/p>\n
![\"\"](\"https:\/\/himinnoghaf.is\/mengunsjavar\/wp-content\/uploads\/mynd2.15-olia-sjavarfang-1.png\")
<\/a>Mynd 2.16. Ol\u00eda hefur mismunandi \u00e1hrif \u00e1 mismunandi sj\u00e1varfang.<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"
Talsvert magn af ol\u00edu fer \u00ed sj\u00f3inn \u00e1 hverju \u00e1ri. Tali\u00f0 er a\u00f0 magni\u00f0 s\u00e9 um 1,3 millj\u00f3nir tonna (e\u00f0a \u00e1 bilinu 0,5-8,3 millj\u00f3nir tonna). \u00dear sem uppspretturnar eru margar og dreif\u00f0ar er mj\u00f6g erfitt er a\u00f0 \u00e1\u00e6tla heildarmagni\u00f0 og Lesa meira…<\/a><\/p>\n","protected":false},"author":2,"featured_media":1750,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11],"tags":[],"class_list":["post-279","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-2-oliaogoliumengun"],"_links":{"self":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts\/279","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/comments?post=279"}],"version-history":[{"count":93,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts\/279\/revisions"}],"predecessor-version":[{"id":3939,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts\/279\/revisions\/3939"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/media\/1750"}],"wp:attachment":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/media?parent=279"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/categories?post=279"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/tags?post=279"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
Rokgjarnasti hluti ol\u00edunnar gufar upp \u00ed andr\u00famslofti\u00f0, en hra\u00f0i uppgufunar er h\u00e1\u00f0ur lofthita og vindhra\u00f0a. Uppgufunin er hra\u00f0ari eftir \u00fev\u00ed sem ol\u00edan hefur h\u00e6rra hlutfall af eimingarefnum me\u00f0 l\u00e1gt su\u00f0umark. Almennt m\u00e1 segja a\u00f0 \u00feeir hlutar ol\u00edunnar sem hafa l\u00e6gra su\u00f0umark en 200\u00b0C gufi upp innan s\u00f3larhrings vi\u00f0 tempra\u00f0ar ve\u00f0ura\u00f0st\u00e6\u00f0ur. Eins og sj\u00e1 m\u00e1 \u00e1 mynd 2.8 er t.d. um 60% hr\u00e1ol\u00edunnar \u00ed flokki 1 me\u00f0 su\u00f0umark undir 200\u00b0C en \u00feetta hlutfall er a\u00f0eins um 5% hj\u00e1 hr\u00e1ol\u00edunni \u00ed flokki 4. \u00dev\u00ed st\u00e6rra sem yfirbor\u00f0sflatarm\u00e1l ol\u00eduflekksins er, \u00fev\u00ed meiri ver\u00f0ur uppgufun l\u00e9ttu eimingarefnanna. Hra\u00f0i \u00fatbrei\u00f0slu ol\u00edunnar fyrst eftir \u00f3happi\u00f0 hefur \u00fev\u00ed einnig \u00e1hrif \u00e1 uppgufunina. \u00d6ldugangur, mikill vindur og h\u00e1r loft- og sj\u00e1varhiti eykur einnig uppgufun. \u00de\u00e6r ol\u00eduleifar sem eftir ver\u00f0a \u00feegar uppgufun hefur \u00e1tt s\u00e9r sta\u00f0, hafa meiri e\u00f0lis\u00feyngd og meiri seigju. \u00deessir \u00fe\u00e6ttir hafa \u00e1hrif \u00e1 frekari ve\u00f0run ol\u00edunnar sem og hva\u00f0a a\u00f0fer\u00f0ir h\u00e6gt er a\u00f0 beita vi\u00f0 hreinsun.<\/p>\n
Ol\u00eduflekkur \u00far unnum ol\u00eduv\u00f6rum (t.d. steinol\u00edu e\u00f0a bens\u00edni) getur gufa\u00f0 algj\u00f6rlega upp \u00e1 nokkrum klukkut\u00edmum. L\u00e9ttar hr\u00e1ol\u00edur geta minnka\u00f0 um helming a\u00f0 umfangi \u00e1 fyrsta s\u00f3larhringnum. \u00deegar \u00f3h\u00f6pp ver\u00f0a \u00e1 loku\u00f0um sv\u00e6\u00f0um me\u00f0 svona rokgjarnar ol\u00edur er eld- og\/e\u00f0a sprengih\u00e6ttan mikil, auk \u00feess sem heilsu f\u00f3lks getur stafa\u00f0 h\u00e6tta af. L\u00edtil sprengih\u00e6tta er af v\u00f6ldum \u00feungra ol\u00eduefna. Hins vegar getur eldh\u00e6tta stafa\u00f0 af \u00feeim, t.d. ef eldur kemur upp \u00ed rusli sem g\u00e6ti veri\u00f0 til sta\u00f0ar \u00ed ol\u00eduflekknum.<\/p>\n
<\/span><\/strong><\/em>Dreifing<\/strong><\/em><\/h6>\nHra\u00f0i dreifingar er a\u00f0allega h\u00e1\u00f0ur e\u00f0liseiginleikum ol\u00edunnar og a\u00f0st\u00e6\u00f0um \u00e1 sj\u00f3. Hra\u00f0ast dreifist l\u00e1gseigju-ol\u00eda \u00ed brotsj\u00f3. \u00d6ldur og i\u00f0ustraumar vi\u00f0 yfirbor\u00f0 sj\u00e1var geta valdi\u00f0 \u00fev\u00ed a\u00f0 hluti e\u00f0a allur flekkurinn brotni upp \u00ed dropa af mismunandi st\u00e6r\u00f0um, sem s\u00ed\u00f0an blandast vi\u00f0 efri l\u00f6g sj\u00e1varins. Litlir dropar haldast \u00ed upplausn en st\u00e6rri droparnir flj\u00f3ta upp \u00e1 yfirbor\u00f0 \u00fear sem \u00feeir anna\u00f0 hvort blandast \u00f6\u00f0rum dropum og endurmynda flekkinn e\u00f0a brei\u00f0ast \u00fat eins og \u00feunn filma. Ol\u00eda me\u00f0 mikla seigju hefur litla tilhneigingu til a\u00f0 dreifast.<\/p>\n
<\/span><\/strong><\/em>Myndun kvo\u00f0ulausnar<\/strong><\/em><\/h6>\nM\u00f6rg ol\u00eduefni taka upp vatn og mynda kvo\u00f0ulausn \u00fear sem vatn er \u00ed ol\u00edudropunum. \u00deetta ferli getur auki\u00f0 r\u00famm\u00e1l mengunarflekksins allt a\u00f0 fimmfalt. Ol\u00edur sem innihalda nikkel og\/e\u00f0a vanad\u00edum \u00ed meira magni en 15 ppm<\/span> e\u00f0a asfalten \u00ed meira magni en 0,5% mynda kvo\u00f0ulausn frekar en a\u00f0rar. Hra\u00f0i kvo\u00f0umyndunar er h\u00e1\u00f0ur vindhra\u00f0a \u2013 \u00fev\u00ed meiri sem vindurinn er \u00fev\u00ed hra\u00f0ar myndast kvo\u00f0an. Ol\u00edur me\u00f0 mikla seigju taka vatn s\u00ed\u00f0ur upp en ol\u00edur me\u00f0 l\u00e6gri seigju. Me\u00f0 t\u00edmanum, \u00feegar ol\u00edan hreyfist me\u00f0 \u00f6ldum, minnka vatnsdroparnir inni \u00ed ol\u00edudropunum og kvo\u00f0an ver\u00f0ur seigari. \u00c1 sama t\u00edma falla tj\u00f6ruefni \u00fat \u00far ol\u00edunni og mynda einskonar h\u00fa\u00f0 utan um vatnsdropana. \u00deetta eykur st\u00f6\u00f0ugleika kvo\u00f0ulausnarinnar. St\u00f6\u00f0ug kvo\u00f0ulausn getur innihaldi\u00f0 70-80% vatn (sj\u00f3) og er oft h\u00e1lfpartinn eins og fast efni. Liturinn \u00e1 \u201e\u00feroska\u00f0ri\u201c kvo\u00f0ulausn er rau\u00f0br\u00fann e\u00f0a jafnvel \u00fat \u00ed appels\u00ednugult. Sl\u00edk kvo\u00f0ulausn er afar \u00fer\u00e1virk<\/span> og getur vi\u00f0haldist \u00ed mj\u00f6g langan t\u00edma. \u00d3st\u00f6\u00f0ugri kvo\u00f0ulausnir skiljast \u00ed sundur \u00ed ol\u00edu og vatn ef \u00fe\u00e6r hitna fyrir tilstilli s\u00f3larlj\u00f3ss \u00ed l\u00e1dau\u00f0um sj\u00f3 e\u00f0a \u00feegar \u00fe\u00e6r berast \u00e1 str\u00f6nd, ef \u00fea\u00f0 \u00e1 anna\u00f0 bor\u00f0 gerist.<\/p>\nMyndun kvo\u00f0ulausnar dregur \u00far \u00e1hrifum annarrar ve\u00f0runar og er helsta \u00e1st\u00e6\u00f0a \u00feess a\u00f0 l\u00e9tt og me\u00f0al\u00feung hr\u00e1ol\u00eda ver\u00f0ur \u00fer\u00e1virk \u00e1 yfirbor\u00f0i sj\u00e1var e\u00f0a vi\u00f0 strendur.<\/p>\n
<\/a>Mynd 2.12. Til vinstri m\u00e1 sj\u00e1 kvo\u00f0ulausn \u00e1 r\u00famsj\u00f3 og \u00ed mi\u00f0junni kvo\u00f0ulausn vi\u00f0 str\u00f6nd. \u00c1 myndinni lengst til h\u00e6gri m\u00e1 sj\u00e1 hvernig h\u00e1lfstorkna\u00f0ir ol\u00eduflekkir hafa myndast \u00fear sem ol\u00eda hefur lent \u00ed sj\u00f3 sem er kaldari en rennslismark ol\u00edunnar. \u00cd \u00feessu tilfelli er um a\u00f0 r\u00e6\u00f0a hr\u00e1ol\u00edu me\u00f0 rennslismark 33\u00b0C og sj\u00f3 vi\u00f0 28\u00b0C.<\/p><\/div>\n
<\/span><\/strong><\/em>Uppleysing<\/strong><\/em><\/h6>\nHra\u00f0i og umfang uppleysingar ol\u00edu \u00ed sj\u00f3 er h\u00e1\u00f0 samsetningu ol\u00edunnar, \u00fatbrei\u00f0slu, sj\u00e1varhita, i\u00f0ustraumum<\/span> og umfangi dreifingar. \u00deyngri eimingarhlutar hr\u00e1ol\u00edu eru n\u00e1nast \u00f3leysanlegir \u00ed vatni. L\u00e9ttari eimingarhlutarnir, s\u00e9r \u00ed lagi ar\u00f3mat\u00edsk vetniskolefni eins og bensen og t\u00f3l\u00faen, leysast hins vegar upp a\u00f0 vissu marki. \u00c1 sama t\u00edma eru \u00feetta rokgj\u00f6rnustu efnin og gufa yfirleitt upp um 10 til 1000 sinnum hra\u00f0ar en \u00feau leysast upp. Styrkur \u00feeirra \u00ed sj\u00f3 er \u00fev\u00ed yfirleitt minni en 1 ppm. Uppleysing \u00e1 \u00fev\u00ed ekki st\u00f3ran \u00fe\u00e1tt \u00ed a\u00f0 fjarl\u00e6gja ol\u00edu af sj\u00e1varyfirbor\u00f0i.<\/p>\n<\/span><\/strong><\/em>Lj\u00f3sni\u00f0urbrot<\/strong><\/em><\/h6>\nOl\u00eda er ger\u00f0 \u00far vetniskolefnum og vetniskolefni geta hvarfast vi\u00f0 s\u00farefni (oxun). Sl\u00edk efnahv\u00f6rf geta leitt annars vegar til myndunar \u00e1 uppleysanlegum efnum og hins vegar \u00e1 \u00fer\u00e1virkum tj\u00f6ruefnum. S\u00f3larlj\u00f3s \u00fdtir undir oxun en jafnvel \u00fe\u00f3tt s\u00f3lar nj\u00f3ti vi\u00f0 eru heildar\u00e1hrif lj\u00f3sni\u00f0urbrots l\u00edtil \u00ed ve\u00f0runarferlinu. \u00deykk l\u00f6g af mj\u00f6g seigri ol\u00edu, e\u00f0a ol\u00edukvo\u00f0u oxast frekar \u00ed \u00fer\u00e1virkar leifar en brotna l\u00edti\u00f0 ni\u00f0ur. \u00deetta stafar af \u00fev\u00ed a\u00f0 \u00ed ferlinu ver\u00f0a til \u00feung efnasamb\u00f6nd\u00a0 sem mynda verndandi yfirbor\u00f0slag (\u00fe.e. yfirbor\u00f0slag sem verndar ol\u00eduflekkinn fyrir frekara ni\u00f0urbroti).<\/p>\n
<\/span><\/strong><\/em>Setmyndun og botnfall<\/strong><\/em><\/h6>\nOl\u00edudropar sem dreif\u00f0ir eru \u00ed sj\u00f3num geta sest \u00e1 svifagnir og l\u00edfr\u00e6nt efni \u00ed upplausn \u00ed sj\u00f3num og \u00feannig or\u00f0i\u00f0 n\u00e6gilega e\u00f0lis\u00feungir til a\u00f0 s\u00f6kkva til botns. Magn sl\u00edkra svifagna er oft miki\u00f0 \u00e1 grunns\u00e6vi og vi\u00f0 \u00e1r\u00f3sa\u00a0 og \u00fear myndast \u00fev\u00ed kj\u00f6ra\u00f0st\u00e6\u00f0ur fyrir setmyndun ol\u00edukenndra agna. Pl\u00f6ntu- og d\u00fdrasvif geta teki\u00f0 ol\u00eduna upp. \u00deannig getur ol\u00edan enda\u00f0 sem hluti af \u00fargangsefnum svifsins og sokki\u00f0 me\u00f0 \u00feeim til botns. Vindborinn sandur e\u00f0a aska getur einnig sest \u00e1 ol\u00edudropa og valdi\u00f0 setmyndun.<\/p>\n
Flestar ol\u00edur eru n\u00e6gjanlega e\u00f0lisl\u00e9ttar til a\u00f0 flj\u00f3ta \u00e1 vatni nema \u00fe\u00e6r ver\u00f0i fyrir \u00e1hrifum \u00feyngri agna. Sumar ol\u00edur, \u00feungar hr\u00e1ol\u00edur, \u00feungar eldsneytisol\u00edur og ol\u00edukvo\u00f0ur hafa e\u00f0lis\u00feyngd sem er n\u00e1l\u00e6gt e\u00f0lis\u00feyngd sj\u00e1var, \u00feannig a\u00f0 l\u00edti\u00f0 \u00fearf af set\u00f6gnum e\u00f0a \u00e1foki til a\u00f0 \u00fe\u00e6r botnfalli. \u00d6rf\u00e1ar \u00feungaol\u00edur hafa meiri e\u00f0lis\u00feyngd en sj\u00f3r og \u00fe\u00e6r botnfalla. Sumar ol\u00edur geta sokki\u00f0 til botns eftir \u00edkveikju, \u00fear sem eldurinn brennir l\u00e9ttari efnunum \u00e1 sama t\u00edma og \u00feung efni myndast vegna hitans.<\/p>\n
\u00cd \u00f3lgusj\u00f3 getur lag af vatni fl\u00e6tt yfir e\u00f0lis\u00feunga ol\u00edu. Vi\u00f0komandi ol\u00eduflekkur getur \u00fe\u00e1 veri\u00f0 \u00ed talsver\u00f0an t\u00edma fyrir ne\u00f0an sj\u00e1varm\u00e1l og \u00fev\u00ed erfitt a\u00f0 finna hann. \u00deegar ve\u00f0ur l\u00e6gir og \u00f6ldugangur minnkar fl\u00fdtur flekkurinn aftur upp \u00e1 yfirbor\u00f0.<\/p>\n
Botnfall ol\u00edumenga\u00f0s sets er ein helsta \u00e1st\u00e6\u00f0a \u00feess a\u00f0 ol\u00edumengun safnast fyrir \u00ed l\u00edfr\u00edki sj\u00e1var. Mj\u00f6g f\u00e1t\u00edtt er a\u00f0 setmyndun eigi s\u00e9r sta\u00f0 annars sta\u00f0ar en \u00e1 grunns\u00e6vi n\u00e1l\u00e6gt str\u00f6nd, og \u00fe\u00e1 a\u00f0allega vegna v\u00edxlverkunar vi\u00f0 strandlengjuna og setagnir sem berast fr\u00e1 henni.<\/p>\n
<\/span><\/strong><\/em>L\u00edfr\u00e6nt ni\u00f0urbrot<\/strong><\/em><\/h6>\n\u00cd sj\u00f3num lifa \u00f6rverur sem geta n\u00fdtt s\u00e9r ol\u00edu til vaxtar og vi\u00f0halds. H\u00e9r er um a\u00f0 r\u00e6\u00f0a bakter\u00edur, sveppi, \u00fe\u00f6runga og frumd\u00fdr, sem n\u00fdtt geta ol\u00edu sem kolefnis- og orkugjafa. Sl\u00edkar l\u00edfverur er a\u00f0 finna um heimsh\u00f6fin en \u00fe\u00e6r eru algengari \u00fear sem n\u00e1tt\u00farlegt a\u00f0streymi ol\u00edu \u00e1 s\u00e9r sta\u00f0 og \u00e1 strandsv\u00e6\u00f0um \u00fear sem st\u00f6\u00f0uga ol\u00edumengun er a\u00f0 finna. Eiginleikar ol\u00edunnar, hitastig og frambo\u00f0 s\u00farefnis og n\u00e6ringarefna (N og P) hafa \u00e1hrif \u00e1 hra\u00f0a og umfang l\u00edfr\u00e6ns ni\u00f0urbrots. Hver \u00f6rverutegund br\u00fdtur yfirleitt ni\u00f0ur \u00e1kve\u00f0in vetniskolefni, \u00feannig a\u00f0 fyrir \u00e1framhaldandi ni\u00f0urbrot \u00fearf margar tegundir \u00f6rvera sem vinna saman e\u00f0a hver \u00e1 eftir annarri. \u00dati \u00e1 r\u00famsj\u00f3 er yfirleitt l\u00edti\u00f0 um \u00fe\u00e6r \u00f6rverur sem \u00fearf \u00ed l\u00edfni\u00f0urbroti\u00f0, en \u00feeim fj\u00f6lgar \u00fe\u00f3 tilt\u00f6lulega hratt \u00feegar ol\u00eda er til sta\u00f0ar. Ni\u00f0urbrot \u00e1 s\u00e9r \u00fe\u00e1 sta\u00f0 \u00fear til skortur ver\u00f0ur \u00e1 s\u00farefni e\u00f0a n\u00e6ringarefnum. \u00de\u00f3 a\u00f0 \u00f6rverur geti broti\u00f0 ni\u00f0ur m\u00f6rg \u00feeirra sambanda sem er a\u00f0 finna \u00ed hr\u00e1ol\u00edu, eru st\u00e6rstu og fl\u00f3knustu sameindirnar illni\u00f0urbrj\u00f3tanlegar.<\/p>\n
\u00dear sem \u00f6rverurnar \u00feurfa n\u00e6ringarefni og s\u00farefni til a\u00f0 geta n\u00fdtt s\u00e9r ol\u00eduefnin, \u00e1 l\u00edfr\u00e6nt ni\u00f0urbrot s\u00e9r einungis sta\u00f0 \u00ed yfirbor\u00f0slagi sj\u00e1var. Vi\u00f0 myndun ol\u00edudropa \u00fati \u00e1 r\u00famsj\u00f3 st\u00e6kkar yfirbor\u00f0i\u00f0 sem \u00f6rverurnar geta athafna\u00f0 sig \u00e1 og \u00fev\u00ed eykst ni\u00f0urbroti\u00f0. \u00c1 hinn b\u00f3ginn hefur \u00feykkt ol\u00edulag vi\u00f0 strandlengjuna e\u00f0a fyrir ofan h\u00e1fj\u00f6ru takmarka\u00f0 yfirbor\u00f0 og takmarka\u00f0a snertingu vi\u00f0 vatn. Vi\u00f0 sl\u00edkar a\u00f0st\u00e6\u00f0ur ver\u00f0ur l\u00edfni\u00f0urbrot mj\u00f6g h\u00e6gt, \u00feannig a\u00f0 ol\u00edan getur veri\u00f0 til sta\u00f0ar \u00ed \u00e1ratugi s\u00e9 h\u00fan ekki fjarl\u00e6g\u00f0.<\/p>\n
\u00dear sem margir \u00fe\u00e6ttir hafa \u00e1hrif \u00e1 l\u00edfni\u00f0urbrot er erfitt a\u00f0 sp\u00e1 fyrir um hversu miklu \u00fea\u00f0 skilar vi\u00f0 ni\u00f0urbrot \u00e1 ol\u00edu. L\u00edfni\u00f0urbrot getur ekki eytt ol\u00edu \u00ed miklu magni, en er til langs t\u00edma ein helsta lei\u00f0in fyrir n\u00e1tt\u00farlega ey\u00f0ingu \u00e1 s\u00ed\u00f0ustu leifum ol\u00edu af strandlengjunni.<\/p>\n
<\/span><\/strong><\/em>Samtvinnun mismunandi ve\u00f0runarferla<\/strong><\/em><\/h6>\n\u00deeir ferlar sem h\u00e9r hafa veri\u00f0 nefndir fara allir \u00ed gang \u00feegar ol\u00eduslys eiga s\u00e9r sta\u00f0, \u00fe\u00f3 a\u00f0 hlutfallslegt v\u00e6gi \u00feeirra s\u00e9 breytilegt eftir \u00fev\u00ed sem t\u00edmanum vindur fram. \u00datbrei\u00f0sla, uppgufun, dreifing, myndun kvo\u00f0ulausnar og uppleysing skipta mestu m\u00e1li stuttu eftir slys. Lj\u00f3sni\u00f0urbrot, setmyndun og l\u00edfni\u00f0urbrot eru hins vegar \u00feeir ferlar sem r\u00e1\u00f0a mestu um endanleg afdrif ol\u00eduflekksins. Dreifing annars vegar og myndun kvo\u00f0ulausnar hins vegar hafa mj\u00f6g \u00f3l\u00edk \u00e1hrif \u00e1 afdrif ol\u00eduflekkja \u00fear sem dreifing flytur ol\u00edu fr\u00e1 yfirbor\u00f0i sj\u00e1var og minnkar \u00fev\u00ed ol\u00eduflekkinn en myndun kvo\u00f0ulausnar eykur umfang hans og \u00fer\u00e1virkni mengunarinnar. \u00deeir \u00fe\u00e6ttir sem hafa \u00e1hrif \u00e1 hvort ol\u00eda dreifist e\u00f0a myndi kvo\u00f0ulausn eru m.a:<\/p>\n
\n- a\u00f0st\u00e6\u00f0ur vi\u00f0 slys (hra\u00f0i og magn ol\u00edu sem sleppur \u00fat \u00ed umhverfi\u00f0, hvort ol\u00edan s\u00e9 losu\u00f0 \u00ed yfirbor\u00f0slag e\u00f0a \u00e1 d\u00fdpi, o.fl.),<\/li>\n
- umhverfisa\u00f0st\u00e6\u00f0ur (hitastig, \u00e1stand sj\u00e1var, straumar, o.fl.) og<\/li>\n
- e\u00f0lis- og efnafr\u00e6\u00f0ilegir eiginleikar ol\u00edunnar.<\/li>\n<\/ul>\n
Mikilv\u00e6gt er a\u00f0 skilja v\u00edxlverkun mismunandi ve\u00f0runarferla til a\u00f0 h\u00e6gt s\u00e9 a\u00f0 sj\u00e1 fyrir hvernig best er a\u00f0 breg\u00f0ast vi\u00f0 ol\u00eduleka.<\/p>\n
2.8.2 \u00c1hrif ol\u00edu \u00e1 l\u00edfr\u00edki<\/h5>\n
Ol\u00eda inniheldur sem fyrr segir m\u00f6rg efnasamb\u00f6nd og eru sum \u00feeirra ska\u00f0leg jafnvel \u00ed litlu magni en \u00f6nnur ekki. Fj\u00f6lhringja ar\u00f3mat\u00edsk vetniskolefni (PAH-efni) eru d\u00e6mi um eitru\u00f0 innihaldsefni ol\u00edu, en \u00feau geta m.a. valdi\u00f0 st\u00f6kkbreytingum og krabbameini \u00ed m\u00f6nnum og d\u00fdrum (sj\u00e1 n\u00e1nari umfj\u00f6llun um PAH \u00ed kafla 5.4<\/a>). Hr\u00e1ol\u00eda, en einnig borv\u00f6kvar og dj\u00fapvatn, geta innihaldi\u00f0 \u00fdmsa eitra\u00f0a m\u00e1lma, svo sem kvikasilfur, bl\u00fd, arsen og kadm\u00edum (sj\u00e1 n\u00e1nari umfj\u00f6llun um \u00feungm\u00e1lma \u00ed kafla 5.3<\/a>). \u00deessir m\u00e1lmar hafa fundist \u00ed h\u00e1um styrk \u00ed seti \u00fear sem ol\u00eduslys hafa or\u00f0i\u00f0. Efnasamb\u00f6nd \u00e1 bor\u00f0 vi\u00f0 PAH og \u00feungm\u00e1lma eru \u00fer\u00e1virk og geta \u00fev\u00ed safnast fyrir \u00ed l\u00edfverum. Ol\u00eduefni geta \u00feannig haft eitur\u00e1hrif \u00e1 l\u00edfr\u00edki hafsins, spillt b\u00fasv\u00e6\u00f0um, skemmt sj\u00e1varfang og dregi\u00f0 verulega \u00far \u00fativistargildi strandsv\u00e6\u00f0a.<\/p>\nSem fyrr segir leysast l\u00e9ttar og \u00feunnflj\u00f3tandi ol\u00edur \u00e1 bor\u00f0 vi\u00f0 bens\u00edn og d\u00edsilol\u00edu betur upp \u00ed vatni en \u00feyngri ol\u00edur (svartol\u00eda, hr\u00e1ol\u00eda), \u00fe\u00f3 a\u00f0 l\u00edklegra s\u00e9 a\u00f0 \u00feessi efni gufi upp. L\u00e9ttari ol\u00edurnar eiga fyrir viki\u00f0 mun grei\u00f0ari a\u00f0gang inn \u00ed l\u00edfr\u00edki\u00f0 og geta \u00feannig valdi\u00f0 miklum eitur\u00e1hrifum. Ar\u00f3mat\u00edski<\/span> hluti ol\u00edunnar sker\u00f0ir til a\u00f0 mynda virkni frumuhimna og hefur sl\u00e6m \u00e1hrif \u00e1 frj\u00f3semi hryggleysingja. Einnig hefur veri\u00f0 sta\u00f0fest a\u00f0 \u00fdmis ol\u00eduefni hafa \u00e1hrif \u00e1 \u00fer\u00f3un hrogna og lirfa og h\u00e6fni \u00feeirra til a\u00f0 lifa af. \u00deyngri og seigari ol\u00eda blandast vatnsmassanum mun verr. H\u00fan fl\u00fdtur ofan \u00e1 og \u00ed efstu l\u00f6gum sj\u00e1var og veldur mikilli yfirbor\u00f0smengun vi\u00f0 strendur. Ol\u00edan leggst \u00e1 spend\u00fdr, fugla, skelfisk, fj\u00f6rugr\u00f3\u00f0ur, \u00feara og l\u00edfr\u00edki\u00f0 almennt.<\/p>\n<\/a>Mynd 2.13. Ol\u00edumengu\u00f0 skjaldbaka og h\u00f6frungur eftir slysi\u00f0 \u00ed Mex\u00edk\u00f3fl\u00f3a 2010.<\/p><\/div>\n
Ol\u00eda hefur einna mest \u00e1hrif \u00e1 sj\u00f3fugla. Fuglar \u00feurfa a\u00f0 vi\u00f0halda h\u00e1um og st\u00f6\u00f0ugum l\u00edkamshita. \u00deegar ol\u00eda kl\u00edstrast \u00e1 fja\u00f0rir \u00feeirra skemmast \u00fe\u00e6r og h\u00e6tta a\u00f0 vera vatnsheldar. \u00dear me\u00f0 minnkar einangrunin og fuglunum ver\u00f0ur kalt. Ol\u00edan \u00feyngir auk \u00feess fuglana og torveldar \u00feeim \u00feannig sund og f\u00e6\u00f0u\u00f6flun. S\u00e9 mengunin mikil ver\u00f0a fuglarnir \u00e1 endanum svo \u00feungir a\u00f0 \u00feeir n\u00e1 ekki til lands og s\u00f6kkva \u00fear af lei\u00f0andi og drukkna. \u00de\u00e1 geta fuglar innbyrt eiturefni \u00feegar \u00feeir reyna a\u00f0 hreinsa fja\u00f0rirnar me\u00f0 goggnum.<\/p>\n
<\/a>Mynd 2.14. Ol\u00edumenga\u00f0ir fuglar.<\/p><\/div>\n
Sem fyrr segir getur hluti ol\u00edunnar enda\u00f0 \u00e1 botninum, \u00fear sem h\u00fan getur haft umtalsver\u00f0 \u00e1hrif \u00e1 botnd\u00fdral\u00edf, b\u00e6\u00f0i vegna eitur\u00e1hrifa og vegna k\u00e6fingar. Kem\u00edsk efni sem hafa veri\u00f0 notu\u00f0 til a\u00f0 f\u00e1st vi\u00f0 ol\u00eduflekki (sj\u00e1 kafla 2.9<\/a>) geta einnig borist me\u00f0 ol\u00edunni til botns og sum \u00feessara efna eru eitru\u00f0. F\u00e6st botnd\u00fdr hafa mikla hreyfigetu og geta \u00fev\u00ed sjaldnast f\u00e6rt sig fr\u00e1 mengu\u00f0um sv\u00e6\u00f0um eins og t.d. fiskar og spend\u00fdr geta oft gert. Sumar fisktegundir n\u00e6rast \u00e1 botnd\u00fdrum og r\u00f3ta \u00ed botnseti og geta \u00feannig fengi\u00f0 \u00ed sig mengunarefni fr\u00e1 hafsbotni. Botngr\u00f3\u00f0ur er au\u00f0vita\u00f0 botnfastur og ver\u00f0ur \u00fev\u00ed a\u00f0 taka \u00fev\u00ed sem til hans berst.<\/p>\n<\/a>Mynd 2.15. K\u00f3rallar, n\u00e6r al\u00feaknir br\u00fanu efni sem inniheldur ol\u00edudropa eftir slysi\u00f0 \u00ed Mex\u00edk\u00f3fl\u00f3a 2010, en \u00fear voru kem\u00edsk efni notu\u00f0 til a\u00f0 f\u00e1st vi\u00f0 ol\u00eduflekkinn.<\/p><\/div>\n
Ol\u00edumengun hefur mismunandi \u00e1hrif \u00e1 sj\u00e1varfang. \u00de\u00e6r sj\u00e1varl\u00edfverur sem vi\u00f0 neytum eru mishreyfanlegar og ver\u00f0a fyrir mismikilli mengun. Fiskar geta synt fr\u00e1 mengu\u00f0um st\u00f6\u00f0um og eru \u00fev\u00ed \u00f3l\u00edklegri til a\u00f0 komast \u00ed snertingu vi\u00f0 flj\u00f3tandi ol\u00edu. \u00deeir geta hins vegar or\u00f0i\u00f0 fyrir \u00e1hrifum uppleystrar ol\u00edu e\u00f0a ol\u00edu sem dreifist \u00ed sj\u00f3num. Eins geta fiskar or\u00f0i\u00f0 fyrir \u00e1hrifum ef b\u00fasv\u00e6\u00f0i mengast. Fiskar taka frekar upp sm\u00e6rri PAH-efni en \u00feau st\u00e6rri. St\u00e6rri PAH-efni eru eitra\u00f0ri og geta valdi\u00f0 krabbameini. PAH-efnin skiljast a\u00f0 mestu leyti \u00far holdi fiska (fiskifl\u00f6kunum) en geta safnast fyrir \u00ed lifur og gallbl\u00f6\u00f0ru. Krabbad\u00fdr eru tilt\u00f6lulega l\u00edti\u00f0 hreyfanleg, en geta \u00fe\u00f3 oft f\u00e6rt sig fr\u00e1 ol\u00edumengu\u00f0um sv\u00e6\u00f0um. B\u00fasv\u00e6\u00f0i krabbad\u00fdra og sta\u00f0ir sem \u00feau n\u00e6ra sig \u00e1 geta einnig veri\u00f0 menga\u00f0ir. \u00dea\u00f0 \u00e1 s\u00e9rstaklega vi\u00f0 um tegundir sem grafa sig ofan \u00ed botnset. L\u00edkt og fiskar taka krabbad\u00fdr upp sm\u00e6rri PAH-efni, en \u00feau skiljast hins vegar ekki eins vel fr\u00e1 holdinu og \u00ed fiskum. Lind\u00fdr \u00e1 bor\u00f0 vi\u00f0 ostrur, kr\u00e6klinga og samlokur eru n\u00e1nast \u00f3hreyfanleg og geta ekki f\u00e6rt sig fr\u00e1 mengu\u00f0um sv\u00e6\u00f0um, en ol\u00eduefni og \u00f6nnur efni safnast einmitt oft fyrir \u00e1 b\u00fasv\u00e6\u00f0um \u00feeirra. L\u00edfr\u00e6n mengunarefni safnast i\u00f0ulega fyrir \u00ed lind\u00fdrum.<\/p>\n
<\/a>Mynd 2.16. Ol\u00eda hefur mismunandi \u00e1hrif \u00e1 mismunandi sj\u00e1varfang.<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"
Talsvert magn af ol\u00edu fer \u00ed sj\u00f3inn \u00e1 hverju \u00e1ri. Tali\u00f0 er a\u00f0 magni\u00f0 s\u00e9 um 1,3 millj\u00f3nir tonna (e\u00f0a \u00e1 bilinu 0,5-8,3 millj\u00f3nir tonna). \u00dear sem uppspretturnar eru margar og dreif\u00f0ar er mj\u00f6g erfitt er a\u00f0 \u00e1\u00e6tla heildarmagni\u00f0 og Lesa meira…<\/a><\/p>\n","protected":false},"author":2,"featured_media":1750,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11],"tags":[],"class_list":["post-279","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-2-oliaogoliumengun"],"_links":{"self":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts\/279","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/comments?post=279"}],"version-history":[{"count":93,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts\/279\/revisions"}],"predecessor-version":[{"id":3939,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts\/279\/revisions\/3939"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/media\/1750"}],"wp:attachment":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/media?parent=279"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/categories?post=279"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/tags?post=279"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
M\u00f6rg ol\u00eduefni taka upp vatn og mynda kvo\u00f0ulausn \u00fear sem vatn er \u00ed ol\u00edudropunum. \u00deetta ferli getur auki\u00f0 r\u00famm\u00e1l mengunarflekksins allt a\u00f0 fimmfalt. Ol\u00edur sem innihalda nikkel og\/e\u00f0a vanad\u00edum \u00ed meira magni en 15 ppm<\/span> e\u00f0a asfalten \u00ed meira magni en 0,5% mynda kvo\u00f0ulausn frekar en a\u00f0rar. Hra\u00f0i kvo\u00f0umyndunar er h\u00e1\u00f0ur vindhra\u00f0a \u2013 \u00fev\u00ed meiri sem vindurinn er \u00fev\u00ed hra\u00f0ar myndast kvo\u00f0an. Ol\u00edur me\u00f0 mikla seigju taka vatn s\u00ed\u00f0ur upp en ol\u00edur me\u00f0 l\u00e6gri seigju. Me\u00f0 t\u00edmanum, \u00feegar ol\u00edan hreyfist me\u00f0 \u00f6ldum, minnka vatnsdroparnir inni \u00ed ol\u00edudropunum og kvo\u00f0an ver\u00f0ur seigari. \u00c1 sama t\u00edma falla tj\u00f6ruefni \u00fat \u00far ol\u00edunni og mynda einskonar h\u00fa\u00f0 utan um vatnsdropana. \u00deetta eykur st\u00f6\u00f0ugleika kvo\u00f0ulausnarinnar. St\u00f6\u00f0ug kvo\u00f0ulausn getur innihaldi\u00f0 70-80% vatn (sj\u00f3) og er oft h\u00e1lfpartinn eins og fast efni. Liturinn \u00e1 \u201e\u00feroska\u00f0ri\u201c kvo\u00f0ulausn er rau\u00f0br\u00fann e\u00f0a jafnvel \u00fat \u00ed appels\u00ednugult. Sl\u00edk kvo\u00f0ulausn er afar \u00fer\u00e1virk<\/span> og getur vi\u00f0haldist \u00ed mj\u00f6g langan t\u00edma. \u00d3st\u00f6\u00f0ugri kvo\u00f0ulausnir skiljast \u00ed sundur \u00ed ol\u00edu og vatn ef \u00fe\u00e6r hitna fyrir tilstilli s\u00f3larlj\u00f3ss \u00ed l\u00e1dau\u00f0um sj\u00f3 e\u00f0a \u00feegar \u00fe\u00e6r berast \u00e1 str\u00f6nd, ef \u00fea\u00f0 \u00e1 anna\u00f0 bor\u00f0 gerist.<\/p>\n Myndun kvo\u00f0ulausnar dregur \u00far \u00e1hrifum annarrar ve\u00f0runar og er helsta \u00e1st\u00e6\u00f0a \u00feess a\u00f0 l\u00e9tt og me\u00f0al\u00feung hr\u00e1ol\u00eda ver\u00f0ur \u00fer\u00e1virk \u00e1 yfirbor\u00f0i sj\u00e1var e\u00f0a vi\u00f0 strendur.<\/p>\n Mynd 2.12. Til vinstri m\u00e1 sj\u00e1 kvo\u00f0ulausn \u00e1 r\u00famsj\u00f3 og \u00ed mi\u00f0junni kvo\u00f0ulausn vi\u00f0 str\u00f6nd. \u00c1 myndinni lengst til h\u00e6gri m\u00e1 sj\u00e1 hvernig h\u00e1lfstorkna\u00f0ir ol\u00eduflekkir hafa myndast \u00fear sem ol\u00eda hefur lent \u00ed sj\u00f3 sem er kaldari en rennslismark ol\u00edunnar. \u00cd \u00feessu tilfelli er um a\u00f0 r\u00e6\u00f0a hr\u00e1ol\u00edu me\u00f0 rennslismark 33\u00b0C og sj\u00f3 vi\u00f0 28\u00b0C.<\/p><\/div>\n Hra\u00f0i og umfang uppleysingar ol\u00edu \u00ed sj\u00f3 er h\u00e1\u00f0 samsetningu ol\u00edunnar, \u00fatbrei\u00f0slu, sj\u00e1varhita, i\u00f0ustraumum<\/span> og umfangi dreifingar. \u00deyngri eimingarhlutar hr\u00e1ol\u00edu eru n\u00e1nast \u00f3leysanlegir \u00ed vatni. L\u00e9ttari eimingarhlutarnir, s\u00e9r \u00ed lagi ar\u00f3mat\u00edsk vetniskolefni eins og bensen og t\u00f3l\u00faen, leysast hins vegar upp a\u00f0 vissu marki. \u00c1 sama t\u00edma eru \u00feetta rokgj\u00f6rnustu efnin og gufa yfirleitt upp um 10 til 1000 sinnum hra\u00f0ar en \u00feau leysast upp. Styrkur \u00feeirra \u00ed sj\u00f3 er \u00fev\u00ed yfirleitt minni en 1 ppm. Uppleysing \u00e1 \u00fev\u00ed ekki st\u00f3ran \u00fe\u00e1tt \u00ed a\u00f0 fjarl\u00e6gja ol\u00edu af sj\u00e1varyfirbor\u00f0i.<\/p>\n Ol\u00eda er ger\u00f0 \u00far vetniskolefnum og vetniskolefni geta hvarfast vi\u00f0 s\u00farefni (oxun). Sl\u00edk efnahv\u00f6rf geta leitt annars vegar til myndunar \u00e1 uppleysanlegum efnum og hins vegar \u00e1 \u00fer\u00e1virkum tj\u00f6ruefnum. S\u00f3larlj\u00f3s \u00fdtir undir oxun en jafnvel \u00fe\u00f3tt s\u00f3lar nj\u00f3ti vi\u00f0 eru heildar\u00e1hrif lj\u00f3sni\u00f0urbrots l\u00edtil \u00ed ve\u00f0runarferlinu. \u00deykk l\u00f6g af mj\u00f6g seigri ol\u00edu, e\u00f0a ol\u00edukvo\u00f0u oxast frekar \u00ed \u00fer\u00e1virkar leifar en brotna l\u00edti\u00f0 ni\u00f0ur. \u00deetta stafar af \u00fev\u00ed a\u00f0 \u00ed ferlinu ver\u00f0a til \u00feung efnasamb\u00f6nd\u00a0 sem mynda verndandi yfirbor\u00f0slag (\u00fe.e. yfirbor\u00f0slag sem verndar ol\u00eduflekkinn fyrir frekara ni\u00f0urbroti).<\/p>\n Ol\u00edudropar sem dreif\u00f0ir eru \u00ed sj\u00f3num geta sest \u00e1 svifagnir og l\u00edfr\u00e6nt efni \u00ed upplausn \u00ed sj\u00f3num og \u00feannig or\u00f0i\u00f0 n\u00e6gilega e\u00f0lis\u00feungir til a\u00f0 s\u00f6kkva til botns. Magn sl\u00edkra svifagna er oft miki\u00f0 \u00e1 grunns\u00e6vi og vi\u00f0 \u00e1r\u00f3sa\u00a0 og \u00fear myndast \u00fev\u00ed kj\u00f6ra\u00f0st\u00e6\u00f0ur fyrir setmyndun ol\u00edukenndra agna. Pl\u00f6ntu- og d\u00fdrasvif geta teki\u00f0 ol\u00eduna upp. \u00deannig getur ol\u00edan enda\u00f0 sem hluti af \u00fargangsefnum svifsins og sokki\u00f0 me\u00f0 \u00feeim til botns. Vindborinn sandur e\u00f0a aska getur einnig sest \u00e1 ol\u00edudropa og valdi\u00f0 setmyndun.<\/p>\n Flestar ol\u00edur eru n\u00e6gjanlega e\u00f0lisl\u00e9ttar til a\u00f0 flj\u00f3ta \u00e1 vatni nema \u00fe\u00e6r ver\u00f0i fyrir \u00e1hrifum \u00feyngri agna. Sumar ol\u00edur, \u00feungar hr\u00e1ol\u00edur, \u00feungar eldsneytisol\u00edur og ol\u00edukvo\u00f0ur hafa e\u00f0lis\u00feyngd sem er n\u00e1l\u00e6gt e\u00f0lis\u00feyngd sj\u00e1var, \u00feannig a\u00f0 l\u00edti\u00f0 \u00fearf af set\u00f6gnum e\u00f0a \u00e1foki til a\u00f0 \u00fe\u00e6r botnfalli. \u00d6rf\u00e1ar \u00feungaol\u00edur hafa meiri e\u00f0lis\u00feyngd en sj\u00f3r og \u00fe\u00e6r botnfalla. Sumar ol\u00edur geta sokki\u00f0 til botns eftir \u00edkveikju, \u00fear sem eldurinn brennir l\u00e9ttari efnunum \u00e1 sama t\u00edma og \u00feung efni myndast vegna hitans.<\/p>\n \u00cd \u00f3lgusj\u00f3 getur lag af vatni fl\u00e6tt yfir e\u00f0lis\u00feunga ol\u00edu. Vi\u00f0komandi ol\u00eduflekkur getur \u00fe\u00e1 veri\u00f0 \u00ed talsver\u00f0an t\u00edma fyrir ne\u00f0an sj\u00e1varm\u00e1l og \u00fev\u00ed erfitt a\u00f0 finna hann. \u00deegar ve\u00f0ur l\u00e6gir og \u00f6ldugangur minnkar fl\u00fdtur flekkurinn aftur upp \u00e1 yfirbor\u00f0.<\/p>\n Botnfall ol\u00edumenga\u00f0s sets er ein helsta \u00e1st\u00e6\u00f0a \u00feess a\u00f0 ol\u00edumengun safnast fyrir \u00ed l\u00edfr\u00edki sj\u00e1var. Mj\u00f6g f\u00e1t\u00edtt er a\u00f0 setmyndun eigi s\u00e9r sta\u00f0 annars sta\u00f0ar en \u00e1 grunns\u00e6vi n\u00e1l\u00e6gt str\u00f6nd, og \u00fe\u00e1 a\u00f0allega vegna v\u00edxlverkunar vi\u00f0 strandlengjuna og setagnir sem berast fr\u00e1 henni.<\/p>\n \u00cd sj\u00f3num lifa \u00f6rverur sem geta n\u00fdtt s\u00e9r ol\u00edu til vaxtar og vi\u00f0halds. H\u00e9r er um a\u00f0 r\u00e6\u00f0a bakter\u00edur, sveppi, \u00fe\u00f6runga og frumd\u00fdr, sem n\u00fdtt geta ol\u00edu sem kolefnis- og orkugjafa. Sl\u00edkar l\u00edfverur er a\u00f0 finna um heimsh\u00f6fin en \u00fe\u00e6r eru algengari \u00fear sem n\u00e1tt\u00farlegt a\u00f0streymi ol\u00edu \u00e1 s\u00e9r sta\u00f0 og \u00e1 strandsv\u00e6\u00f0um \u00fear sem st\u00f6\u00f0uga ol\u00edumengun er a\u00f0 finna. Eiginleikar ol\u00edunnar, hitastig og frambo\u00f0 s\u00farefnis og n\u00e6ringarefna (N og P) hafa \u00e1hrif \u00e1 hra\u00f0a og umfang l\u00edfr\u00e6ns ni\u00f0urbrots. Hver \u00f6rverutegund br\u00fdtur yfirleitt ni\u00f0ur \u00e1kve\u00f0in vetniskolefni, \u00feannig a\u00f0 fyrir \u00e1framhaldandi ni\u00f0urbrot \u00fearf margar tegundir \u00f6rvera sem vinna saman e\u00f0a hver \u00e1 eftir annarri. \u00dati \u00e1 r\u00famsj\u00f3 er yfirleitt l\u00edti\u00f0 um \u00fe\u00e6r \u00f6rverur sem \u00fearf \u00ed l\u00edfni\u00f0urbroti\u00f0, en \u00feeim fj\u00f6lgar \u00fe\u00f3 tilt\u00f6lulega hratt \u00feegar ol\u00eda er til sta\u00f0ar. Ni\u00f0urbrot \u00e1 s\u00e9r \u00fe\u00e1 sta\u00f0 \u00fear til skortur ver\u00f0ur \u00e1 s\u00farefni e\u00f0a n\u00e6ringarefnum. \u00de\u00f3 a\u00f0 \u00f6rverur geti broti\u00f0 ni\u00f0ur m\u00f6rg \u00feeirra sambanda sem er a\u00f0 finna \u00ed hr\u00e1ol\u00edu, eru st\u00e6rstu og fl\u00f3knustu sameindirnar illni\u00f0urbrj\u00f3tanlegar.<\/p>\n \u00dear sem \u00f6rverurnar \u00feurfa n\u00e6ringarefni og s\u00farefni til a\u00f0 geta n\u00fdtt s\u00e9r ol\u00eduefnin, \u00e1 l\u00edfr\u00e6nt ni\u00f0urbrot s\u00e9r einungis sta\u00f0 \u00ed yfirbor\u00f0slagi sj\u00e1var. Vi\u00f0 myndun ol\u00edudropa \u00fati \u00e1 r\u00famsj\u00f3 st\u00e6kkar yfirbor\u00f0i\u00f0 sem \u00f6rverurnar geta athafna\u00f0 sig \u00e1 og \u00fev\u00ed eykst ni\u00f0urbroti\u00f0. \u00c1 hinn b\u00f3ginn hefur \u00feykkt ol\u00edulag vi\u00f0 strandlengjuna e\u00f0a fyrir ofan h\u00e1fj\u00f6ru takmarka\u00f0 yfirbor\u00f0 og takmarka\u00f0a snertingu vi\u00f0 vatn. Vi\u00f0 sl\u00edkar a\u00f0st\u00e6\u00f0ur ver\u00f0ur l\u00edfni\u00f0urbrot mj\u00f6g h\u00e6gt, \u00feannig a\u00f0 ol\u00edan getur veri\u00f0 til sta\u00f0ar \u00ed \u00e1ratugi s\u00e9 h\u00fan ekki fjarl\u00e6g\u00f0.<\/p>\n \u00dear sem margir \u00fe\u00e6ttir hafa \u00e1hrif \u00e1 l\u00edfni\u00f0urbrot er erfitt a\u00f0 sp\u00e1 fyrir um hversu miklu \u00fea\u00f0 skilar vi\u00f0 ni\u00f0urbrot \u00e1 ol\u00edu. L\u00edfni\u00f0urbrot getur ekki eytt ol\u00edu \u00ed miklu magni, en er til langs t\u00edma ein helsta lei\u00f0in fyrir n\u00e1tt\u00farlega ey\u00f0ingu \u00e1 s\u00ed\u00f0ustu leifum ol\u00edu af strandlengjunni.<\/p>\n \u00deeir ferlar sem h\u00e9r hafa veri\u00f0 nefndir fara allir \u00ed gang \u00feegar ol\u00eduslys eiga s\u00e9r sta\u00f0, \u00fe\u00f3 a\u00f0 hlutfallslegt v\u00e6gi \u00feeirra s\u00e9 breytilegt eftir \u00fev\u00ed sem t\u00edmanum vindur fram. \u00datbrei\u00f0sla, uppgufun, dreifing, myndun kvo\u00f0ulausnar og uppleysing skipta mestu m\u00e1li stuttu eftir slys. Lj\u00f3sni\u00f0urbrot, setmyndun og l\u00edfni\u00f0urbrot eru hins vegar \u00feeir ferlar sem r\u00e1\u00f0a mestu um endanleg afdrif ol\u00eduflekksins. Dreifing annars vegar og myndun kvo\u00f0ulausnar hins vegar hafa mj\u00f6g \u00f3l\u00edk \u00e1hrif \u00e1 afdrif ol\u00eduflekkja \u00fear sem dreifing flytur ol\u00edu fr\u00e1 yfirbor\u00f0i sj\u00e1var og minnkar \u00fev\u00ed ol\u00eduflekkinn en myndun kvo\u00f0ulausnar eykur umfang hans og \u00fer\u00e1virkni mengunarinnar. \u00deeir \u00fe\u00e6ttir sem hafa \u00e1hrif \u00e1 hvort ol\u00eda dreifist e\u00f0a myndi kvo\u00f0ulausn eru m.a:<\/p>\n Mikilv\u00e6gt er a\u00f0 skilja v\u00edxlverkun mismunandi ve\u00f0runarferla til a\u00f0 h\u00e6gt s\u00e9 a\u00f0 sj\u00e1 fyrir hvernig best er a\u00f0 breg\u00f0ast vi\u00f0 ol\u00eduleka.<\/p>\n Ol\u00eda inniheldur sem fyrr segir m\u00f6rg efnasamb\u00f6nd og eru sum \u00feeirra ska\u00f0leg jafnvel \u00ed litlu magni en \u00f6nnur ekki. Fj\u00f6lhringja ar\u00f3mat\u00edsk vetniskolefni (PAH-efni) eru d\u00e6mi um eitru\u00f0 innihaldsefni ol\u00edu, en \u00feau geta m.a. valdi\u00f0 st\u00f6kkbreytingum og krabbameini \u00ed m\u00f6nnum og d\u00fdrum (sj\u00e1 n\u00e1nari umfj\u00f6llun um PAH \u00ed kafla 5.4<\/a>). Hr\u00e1ol\u00eda, en einnig borv\u00f6kvar og dj\u00fapvatn, geta innihaldi\u00f0 \u00fdmsa eitra\u00f0a m\u00e1lma, svo sem kvikasilfur, bl\u00fd, arsen og kadm\u00edum (sj\u00e1 n\u00e1nari umfj\u00f6llun um \u00feungm\u00e1lma \u00ed kafla 5.3<\/a>). \u00deessir m\u00e1lmar hafa fundist \u00ed h\u00e1um styrk \u00ed seti \u00fear sem ol\u00eduslys hafa or\u00f0i\u00f0. Efnasamb\u00f6nd \u00e1 bor\u00f0 vi\u00f0 PAH og \u00feungm\u00e1lma eru \u00fer\u00e1virk og geta \u00fev\u00ed safnast fyrir \u00ed l\u00edfverum. Ol\u00eduefni geta \u00feannig haft eitur\u00e1hrif \u00e1 l\u00edfr\u00edki hafsins, spillt b\u00fasv\u00e6\u00f0um, skemmt sj\u00e1varfang og dregi\u00f0 verulega \u00far \u00fativistargildi strandsv\u00e6\u00f0a.<\/p>\n Sem fyrr segir leysast l\u00e9ttar og \u00feunnflj\u00f3tandi ol\u00edur \u00e1 bor\u00f0 vi\u00f0 bens\u00edn og d\u00edsilol\u00edu betur upp \u00ed vatni en \u00feyngri ol\u00edur (svartol\u00eda, hr\u00e1ol\u00eda), \u00fe\u00f3 a\u00f0 l\u00edklegra s\u00e9 a\u00f0 \u00feessi efni gufi upp. L\u00e9ttari ol\u00edurnar eiga fyrir viki\u00f0 mun grei\u00f0ari a\u00f0gang inn \u00ed l\u00edfr\u00edki\u00f0 og geta \u00feannig valdi\u00f0 miklum eitur\u00e1hrifum. Ar\u00f3mat\u00edski<\/span> hluti ol\u00edunnar sker\u00f0ir til a\u00f0 mynda virkni frumuhimna og hefur sl\u00e6m \u00e1hrif \u00e1 frj\u00f3semi hryggleysingja. Einnig hefur veri\u00f0 sta\u00f0fest a\u00f0 \u00fdmis ol\u00eduefni hafa \u00e1hrif \u00e1 \u00fer\u00f3un hrogna og lirfa og h\u00e6fni \u00feeirra til a\u00f0 lifa af. \u00deyngri og seigari ol\u00eda blandast vatnsmassanum mun verr. H\u00fan fl\u00fdtur ofan \u00e1 og \u00ed efstu l\u00f6gum sj\u00e1var og veldur mikilli yfirbor\u00f0smengun vi\u00f0 strendur. Ol\u00edan leggst \u00e1 spend\u00fdr, fugla, skelfisk, fj\u00f6rugr\u00f3\u00f0ur, \u00feara og l\u00edfr\u00edki\u00f0 almennt.<\/p>\n Mynd 2.13. Ol\u00edumengu\u00f0 skjaldbaka og h\u00f6frungur eftir slysi\u00f0 \u00ed Mex\u00edk\u00f3fl\u00f3a 2010.<\/p><\/div>\n Ol\u00eda hefur einna mest \u00e1hrif \u00e1 sj\u00f3fugla. Fuglar \u00feurfa a\u00f0 vi\u00f0halda h\u00e1um og st\u00f6\u00f0ugum l\u00edkamshita. \u00deegar ol\u00eda kl\u00edstrast \u00e1 fja\u00f0rir \u00feeirra skemmast \u00fe\u00e6r og h\u00e6tta a\u00f0 vera vatnsheldar. \u00dear me\u00f0 minnkar einangrunin og fuglunum ver\u00f0ur kalt. Ol\u00edan \u00feyngir auk \u00feess fuglana og torveldar \u00feeim \u00feannig sund og f\u00e6\u00f0u\u00f6flun. S\u00e9 mengunin mikil ver\u00f0a fuglarnir \u00e1 endanum svo \u00feungir a\u00f0 \u00feeir n\u00e1 ekki til lands og s\u00f6kkva \u00fear af lei\u00f0andi og drukkna. \u00de\u00e1 geta fuglar innbyrt eiturefni \u00feegar \u00feeir reyna a\u00f0 hreinsa fja\u00f0rirnar me\u00f0 goggnum.<\/p>\n Mynd 2.14. Ol\u00edumenga\u00f0ir fuglar.<\/p><\/div>\n Sem fyrr segir getur hluti ol\u00edunnar enda\u00f0 \u00e1 botninum, \u00fear sem h\u00fan getur haft umtalsver\u00f0 \u00e1hrif \u00e1 botnd\u00fdral\u00edf, b\u00e6\u00f0i vegna eitur\u00e1hrifa og vegna k\u00e6fingar. Kem\u00edsk efni sem hafa veri\u00f0 notu\u00f0 til a\u00f0 f\u00e1st vi\u00f0 ol\u00eduflekki (sj\u00e1 kafla 2.9<\/a>) geta einnig borist me\u00f0 ol\u00edunni til botns og sum \u00feessara efna eru eitru\u00f0. F\u00e6st botnd\u00fdr hafa mikla hreyfigetu og geta \u00fev\u00ed sjaldnast f\u00e6rt sig fr\u00e1 mengu\u00f0um sv\u00e6\u00f0um eins og t.d. fiskar og spend\u00fdr geta oft gert. Sumar fisktegundir n\u00e6rast \u00e1 botnd\u00fdrum og r\u00f3ta \u00ed botnseti og geta \u00feannig fengi\u00f0 \u00ed sig mengunarefni fr\u00e1 hafsbotni. Botngr\u00f3\u00f0ur er au\u00f0vita\u00f0 botnfastur og ver\u00f0ur \u00fev\u00ed a\u00f0 taka \u00fev\u00ed sem til hans berst.<\/p>\n Mynd 2.15. K\u00f3rallar, n\u00e6r al\u00feaknir br\u00fanu efni sem inniheldur ol\u00edudropa eftir slysi\u00f0 \u00ed Mex\u00edk\u00f3fl\u00f3a 2010, en \u00fear voru kem\u00edsk efni notu\u00f0 til a\u00f0 f\u00e1st vi\u00f0 ol\u00eduflekkinn.<\/p><\/div>\n Ol\u00edumengun hefur mismunandi \u00e1hrif \u00e1 sj\u00e1varfang. \u00de\u00e6r sj\u00e1varl\u00edfverur sem vi\u00f0 neytum eru mishreyfanlegar og ver\u00f0a fyrir mismikilli mengun. Fiskar geta synt fr\u00e1 mengu\u00f0um st\u00f6\u00f0um og eru \u00fev\u00ed \u00f3l\u00edklegri til a\u00f0 komast \u00ed snertingu vi\u00f0 flj\u00f3tandi ol\u00edu. \u00deeir geta hins vegar or\u00f0i\u00f0 fyrir \u00e1hrifum uppleystrar ol\u00edu e\u00f0a ol\u00edu sem dreifist \u00ed sj\u00f3num. Eins geta fiskar or\u00f0i\u00f0 fyrir \u00e1hrifum ef b\u00fasv\u00e6\u00f0i mengast. Fiskar taka frekar upp sm\u00e6rri PAH-efni en \u00feau st\u00e6rri. St\u00e6rri PAH-efni eru eitra\u00f0ri og geta valdi\u00f0 krabbameini. PAH-efnin skiljast a\u00f0 mestu leyti \u00far holdi fiska (fiskifl\u00f6kunum) en geta safnast fyrir \u00ed lifur og gallbl\u00f6\u00f0ru. Krabbad\u00fdr eru tilt\u00f6lulega l\u00edti\u00f0 hreyfanleg, en geta \u00fe\u00f3 oft f\u00e6rt sig fr\u00e1 ol\u00edumengu\u00f0um sv\u00e6\u00f0um. B\u00fasv\u00e6\u00f0i krabbad\u00fdra og sta\u00f0ir sem \u00feau n\u00e6ra sig \u00e1 geta einnig veri\u00f0 menga\u00f0ir. \u00dea\u00f0 \u00e1 s\u00e9rstaklega vi\u00f0 um tegundir sem grafa sig ofan \u00ed botnset. L\u00edkt og fiskar taka krabbad\u00fdr upp sm\u00e6rri PAH-efni, en \u00feau skiljast hins vegar ekki eins vel fr\u00e1 holdinu og \u00ed fiskum. Lind\u00fdr \u00e1 bor\u00f0 vi\u00f0 ostrur, kr\u00e6klinga og samlokur eru n\u00e1nast \u00f3hreyfanleg og geta ekki f\u00e6rt sig fr\u00e1 mengu\u00f0um sv\u00e6\u00f0um, en ol\u00eduefni og \u00f6nnur efni safnast einmitt oft fyrir \u00e1 b\u00fasv\u00e6\u00f0um \u00feeirra. L\u00edfr\u00e6n mengunarefni safnast i\u00f0ulega fyrir \u00ed lind\u00fdrum.<\/p>\n Mynd 2.16. Ol\u00eda hefur mismunandi \u00e1hrif \u00e1 mismunandi sj\u00e1varfang.<\/p><\/div>\n","protected":false},"excerpt":{"rendered":" Talsvert magn af ol\u00edu fer \u00ed sj\u00f3inn \u00e1 hverju \u00e1ri. Tali\u00f0 er a\u00f0 magni\u00f0 s\u00e9 um 1,3 millj\u00f3nir tonna (e\u00f0a \u00e1 bilinu 0,5-8,3 millj\u00f3nir tonna). \u00dear sem uppspretturnar eru margar og dreif\u00f0ar er mj\u00f6g erfitt er a\u00f0 \u00e1\u00e6tla heildarmagni\u00f0 og Lesa meira…<\/a><\/p>\n","protected":false},"author":2,"featured_media":1750,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11],"tags":[],"class_list":["post-279","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-2-oliaogoliumengun"],"_links":{"self":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts\/279","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/comments?post=279"}],"version-history":[{"count":93,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts\/279\/revisions"}],"predecessor-version":[{"id":3939,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts\/279\/revisions\/3939"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/media\/1750"}],"wp:attachment":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/media?parent=279"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/categories?post=279"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/tags?post=279"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}<\/a><\/span><\/strong><\/em>Uppleysing<\/strong><\/em><\/h6>\n
<\/span><\/strong><\/em>Lj\u00f3sni\u00f0urbrot<\/strong><\/em><\/h6>\n
<\/span><\/strong><\/em>Setmyndun og botnfall<\/strong><\/em><\/h6>\n
<\/span><\/strong><\/em>L\u00edfr\u00e6nt ni\u00f0urbrot<\/strong><\/em><\/h6>\n
<\/span><\/strong><\/em>Samtvinnun mismunandi ve\u00f0runarferla<\/strong><\/em><\/h6>\n
\n
2.8.2 \u00c1hrif ol\u00edu \u00e1 l\u00edfr\u00edki<\/h5>\n
<\/a><\/a><\/a><\/a>