P\u0159ibli\u017en\u011b p\u0159ed 252 miliony let za\u017eila Zem\u011b sv\u00e9 nejhor\u0161\u00ed hromadn\u00e9 vym\u00edr\u00e1n\u00ed, zn\u00e1m\u00e9 jako Velk\u00e9 vym\u00edr\u00e1n\u00ed. B\u011bhem t\u00e9to katastrofick\u00e9 ud\u00e1losti vym\u0159elo odhadem 75 % suchozemsk\u00fdch druh\u016f a 90 % mo\u0159sk\u00fdch druh\u016f. Tato ud\u00e1lost vym\u00edr\u00e1n\u00ed byla po cel\u00e1 desetilet\u00ed z\u00e1hadou a v\u011bdci hledali vin\u00edka zodpov\u011bdn\u00e9ho za tak rozs\u00e1hlou devastaci.<\/p>\n\n
Jedn\u00edm z hlavn\u00edch podez\u0159el\u00fdch ve Velk\u00e9m vym\u00edr\u00e1n\u00ed je s\u00e9rie masivn\u00edch sope\u010dn\u00fdch erupc\u00ed zn\u00e1m\u00fdch jako Sibi\u0159sk\u00e9 trapy. Tyto erupce vyvrhly na zemsk\u00fd povrch obrovsk\u00e9 mno\u017estv\u00ed magmatu a l\u00e1vy a pokryly oblast Sibi\u0159e, kter\u00e1 se rovn\u00e1 cel\u00e9 z\u00e1padn\u00ed Evrop\u011b. V\u011bdci se domn\u00edvaj\u00ed, \u017ee tyto erupce mohly do atmosf\u00e9ry uvolnit jedovat\u00e9 plyny a \u010d\u00e1stice, co\u017e vedlo ke glob\u00e1ln\u00ed ekologick\u00e9 katastrof\u011b.<\/p>\n\n
Aby bylo mo\u017en\u00e9 ur\u010dit, zda erupce sibi\u0159sk\u00fdch trap\u016f byly spou\u0161t\u011b\u010dem Velk\u00e9ho vym\u00edr\u00e1n\u00ed, museli v\u011bdci stanovit p\u0159esnou \u010dasovou osu obou ud\u00e1lost\u00ed. D\u0159\u00edv\u011bj\u0161\u00ed studie odhadovaly, \u017ee ob\u011b ud\u00e1losti nastaly v rozmez\u00ed n\u011bkolika milion\u016f let od sebe, ale p\u0159esn\u00e1 posloupnost byla nejist\u00e1.<\/p>\n\n
Ned\u00e1vn\u00e9 v\u00fdzkumy poskytly p\u0159esn\u011bj\u0161\u00ed datov\u00e1n\u00ed jak hromadn\u00e9ho vym\u00edr\u00e1n\u00ed, tak erupc\u00ed sibi\u0159sk\u00fdch trap\u016f. V\u011bdci zjistili, \u017ee ud\u00e1lost hromadn\u00e9ho vym\u00edr\u00e1n\u00ed nastala v obdob\u00ed 60 000 let p\u0159ed 252 miliony let. Vypo\u010d\u00edtali tak\u00e9, \u017ee erupce sibi\u0159sk\u00fdch trap\u016f za\u010daly asi 300 000 let p\u0159ed hromadn\u00fdm vym\u00edr\u00e1n\u00edm a pokra\u010dovaly asi 500 000 let po n\u011bm.<\/p>\n\n
Nov\u00e1 \u010dasov\u00e1 osa nazna\u010duje, \u017ee magmatismus ze sibi\u0159sk\u00fdch trap\u016f byl mo\u017en\u00fdm spou\u0161t\u011b\u010dem Velk\u00e9ho vym\u00edr\u00e1n\u00ed. V\u011bdci v\u0161ak st\u00e1le zkoumaj\u00ed, pro\u010d hromadn\u00e9 vym\u00edr\u00e1n\u00ed neza\u010dalo d\u0159\u00edve ne\u017e stovky tis\u00edc let po za\u010d\u00e1tku erupc\u00ed. Jedna teorie \u0159\u00edk\u00e1, \u017ee planeta dos\u00e1hla bodu zvratu a\u017e pot\u00e9, co vybuchlo kritick\u00e9 mno\u017estv\u00ed magmatu. Dal\u0161\u00ed mo\u017enost\u00ed je, \u017ee a\u017e t\u011bsn\u011b p\u0159ed za\u010d\u00e1tkem hromadn\u00e9ho vym\u00edr\u00e1n\u00ed vybuchlo pouze mal\u00e9 mno\u017estv\u00ed magmatu.<\/p>\n\n
Erupce sibi\u0159sk\u00fdch trap\u016f m\u011bly hlubok\u00fd dopad na zemsk\u00e9 prost\u0159ed\u00ed. Krom\u011b uvoln\u011bn\u00ed magmatu a l\u00e1vy uvolnily erupce do atmosf\u00e9ry tak\u00e9 obrovsk\u00e9 mno\u017estv\u00ed oxidu uhli\u010dit\u00e9ho. To zp\u016fsobilo prudk\u00fd n\u00e1r\u016fst kyselosti oce\u00e1n\u016f, co\u017e by vyhnalo mnoho mo\u0159sk\u00fdch druh\u016f k vyhynut\u00ed.<\/p>\n\n
Vyhynut\u00ed \u010delili tak\u00e9 suchozem\u0161t\u00ed \u017eivo\u010dichov\u00e9, i kdy\u017e p\u0159esn\u00e9 p\u0159\u00ed\u010diny jsou st\u00e1le nejasn\u00e9. Teorie zahrnuj\u00ed vysok\u00e9 atmosf\u00e9rick\u00e9 teploty, obrovsk\u00e9 po\u017e\u00e1ry a d\u00e9\u0161\u0165 kysel\u00fd jako citronov\u00e1 \u0161\u0165\u00e1va.<\/p>\n\n
P\u0159esto\u017ee v\u011bdci dos\u00e1hli zna\u010dn\u00e9ho pokroku v porozum\u011bn\u00ed Velk\u00e9ho vym\u00edr\u00e1n\u00ed, mnoho ot\u00e1zek z\u016fst\u00e1v\u00e1 nezodpov\u011bzeno. V\u00fdzkumn\u00edci st\u00e1le zkoumaj\u00ed p\u0159esn\u00e9 mechanismy, kter\u00fdmi magmatismus ze sibi\u0159sk\u00fdch trap\u016f zp\u016fsobil tak rozs\u00e1hlou devastaci. Zkoumaj\u00ed tak\u00e9 dopady erupc\u00ed na \u017eivotn\u00ed prost\u0159ed\u00ed a dlouhodob\u00e9 d\u016fsledky permsk\u00e9ho vym\u00edr\u00e1n\u00ed.<\/p>\n\n
Velk\u00e9 vym\u00edr\u00e1n\u00ed m\u011blo hlubok\u00fd dopad na v\u00fdvoj \u017eivota na Zemi. Vym\u00edr\u00e1n\u00ed \u010detn\u00fdch druh\u016f vytvo\u0159ilo ekologick\u00e9 niky, kter\u00e9 umo\u017enily vznik a diverzifikaci nov\u00fdch druh\u016f. Tato ud\u00e1lost sehr\u00e1la kl\u00ed\u010dovou roli p\u0159i formov\u00e1n\u00ed biodiverzity, kterou dnes vid\u00edme.<\/p>\n\n
Pochopen\u00ed Velk\u00e9ho vym\u00edr\u00e1n\u00ed nejen poskytuje poznatky o geologick\u00e9 historii Zem\u011b, ale m\u00e1 tak\u00e9 d\u016fsledky pro budoucnost. Studiem d\u0159\u00edv\u011bj\u0161\u00edch hromadn\u00fdch vym\u00edr\u00e1n\u00ed mohou v\u011bdci z\u00edskat cenn\u00e9 poznatky o potenci\u00e1ln\u00edch dopadech budouc\u00edch ekologick\u00fdch katastrof a o tom, jak by na takov\u00e9 v\u00fdzvy mohl reagovat \u017eivot na Zemi.<\/p>","protected":false},"excerpt":{"rendered":"
Velk\u00e9 vym\u00edr\u00e1n\u00ed: Zni\u010duj\u00edc\u00ed hromadn\u00e9 vym\u00edr\u00e1n\u00ed Permsk\u00e9 vym\u00edr\u00e1n\u00ed: Nejhor\u0161\u00ed hromadn\u00e9 vym\u00edr\u00e1n\u00ed na Zemi P\u0159ibli\u017en\u011b p\u0159ed 252 miliony let za\u017eila Zem\u011b sv\u00e9 nejhor\u0161\u00ed hromadn\u00e9 vym\u00edr\u00e1n\u00ed, zn\u00e1m\u00e9 jako Velk\u00e9 vym\u00edr\u00e1n\u00ed. B\u011bhem t\u00e9to katastrofick\u00e9…<\/p>\n","protected":false},"author":6,"featured_media":24006,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[138],"tags":[36,207,561,137,559,560,558],"class_list":["post-201","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-paleontology","tag-environmental-science","tag-geology","tag-mass-extinction","tag-paleontology","tag-permian-extinction","tag-siberian-traps","tag-great-dying"],"_links":{"self":[{"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/posts\/201","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/comments?post=201"}],"version-history":[{"count":1,"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/posts\/201\/revisions"}],"predecessor-version":[{"id":202,"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/posts\/201\/revisions\/202"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/media\/24006"}],"wp:attachment":[{"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/media?parent=201"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/categories?post=201"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/tags?post=201"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}