Rushewar gandun daji na Carboniferous

Rushewar gandun daji na Carboniferous ( CRC ) wani ƙaramin ɓarna ne wanda ya faru kusan shekaru miliyan 305 da suka gabata a lokacin Carboniferous .  Lamarin ya faru ne a ƙarshen Moscovian kuma ya ci gaba zuwa farkon matakan Kasimovian na Pennsylvania (Upper Carboniferous).

Ya canza manyan gandun daji na kwal wanda ya rufe yankin equatorial na Euramerica (Yuropa da Arewacin Amurka). Wannan taron na iya ragargaza gandun daji zuwa mafaka mai nisa ko "tsibirai" na muhalli, wanda hakan ya karfafa dwarfism kuma, jim kadan bayan haka, halaka yawancin nau'ikan shuke-shuke da dabbobi. Bayan taron, gandun daji na wurare masu zafi sun ci gaba a manyan yankuna na Duniya, amma an canza girman su da abun da ke ciki. 

 Tsarin lalacewa a ƙasa 
A cikin Carboniferous, manyan gandun daji na wurare masu zafi na Euramerica sun goyi bayan lycopodiophyta mai tsawo, cakuda tsire-tsire daban-daban, da kuma bambancin rayuwar dabbobi: giant griffinflies, millipedes, blattopterans, karamin amphibians, da amniotes na farko.

 Shuke-shuke 
Haɓakar gandun daji a cikin Carboniferous ya canza yanayin ƙasa sosai ta hanyar lalata ƙananan makamashi, tsarin kogi mai wadataccen kwayoyin halitta tare da tashoshi da yawa da tsibirai masu ɗorewa. Ci gaba da juyin halitta na tsire-tsire masu kama da itace ya kara kwanciyar hankali na ambaliyar ruwa (ƙarancin rushewa da motsi) ta hanyar yawan gandun daji na ambaliwar ruwa, samar da tarkace mai laushi, da karuwa a cikin rikitarwa da bambancin tarkace.

Rushewa ya faru ne ta hanyar jerin canje-canje. Da farko akwai karuwar sannu a hankali a cikin mitar ferns masu amfani da dama a ƙarshen zamanin Moscovian. Wannan ya biyo baya a cikin Kasimovian na farko ta hanyar babban, ba yawo ba tsammani lalacewar lycopsids masu rinjaye da canji ga tsarin halittu na fern. Wannan ya tabbatar da wani binciken da aka yi a shekara ta 2011 wanda ya nuna cewa kasancewar koguna masu juyawa da anabranching, abubuwan da suka faru na manyan tarkace, da kuma rikodin jams sun ragu sosai a iyakar Moscovian-Kasimovian.Davies, N.S.; Gibling, M. R. (2011). "Evolution of fixed-channel alluvial plains in response to Carboniferous vegetation". Nature Geoscience. 21 (9): 629–633. Bibcode:2011NatGe...4..629D. doi:10.1038/ngeo1237. An ragargaza gandun daji, suna samar da 'tsibirin' da ke raguwa, kuma a cikin sabon lokacin Kasimovian, gandun daji sun ɓace daga tarihin burbushin halittu. Ƙananan haɗuwa da nau'ikan shuke-shuke daban-daban sun faru a duk wannan canjin; tarin furanni sun kasance masu hankali sosai kuma masu ra'ayin mazan jiya kuma sun ba da damar sababbin ba tare da wani nau'in tsakiya na tsakiya ba dangane da wanda ya gabata da wanda ya biyo baya.

 Dabbobi marasa rai 
Tarihin burbushin kwari na iya zama da wahala a yi nazari, saboda yawanci karami da kuma yanayin jikinsu. Ɗaya daga cikin binciken ya lissafa ƙimar asali da halaka fiye da 600 na iyalai na dabbobi na ƙasa da na ruwa mai laushi. Yankunan su na stratigraphic sun kunshi wani lokaci na geologic daga tsakiyar Paleozoic biotic mamayewar ƙasar zuwa Permian-Triassic. Insects sun ƙunshi fiye da rabin iyalai da aka samo, mafi yawansu daga Euramerica mai zafi ne. Wannan binciken ya sami bugun lalacewar ƙarshen Pennsylvanian wanda ke nuna yanayin bushewa da sauyawa na lycopod zuwa bishiyoyi masu rinjaye na fern. 

 Dabbobi masu ƙashi 
Kafin rushewar, rarraba nau'in dabbobi na kashin baya ya kasance mai yawa, tare da nau'in iri ɗaya da ke cikin yankin Pangaea mai zafi. Bayan rushewar, kowane gandun daji mai rai 'tsibiran' ya haɓaka nasa nau'in jinsuna na musamman. Yawancin nau'o'in amphibian sun ƙare, yayin da kakannin dabbobi masu rarrafe da dabbobi masu shayarwa suka bambanta zuwa wasu nau'o-nau'i bayan rikicin farko. Wadannan alamu an bayyana su ta hanyar ka'idar illar biogeography, ra'ayi wanda ke bayyana yadda juyin halitta ke ci gaba lokacin da aka ƙuntata yawan jama'a a cikin aljihun da aka ware. Wannan ka'idar an samo asali ne daga tsibirai na teku, amma ana iya amfani da shi daidai ga kowane tsarin halittu wanda ya ragargaje, kawai yana cikin ƙananan wurare kuma yana kewaye da wani wurin zama mara kyau.

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