Kanadha Subartic Lakes
Kuderera kwekunaya nenzira yechando kunoonekwa mumakore achangopfuura mu nzvimbo dzesanyika Canada yakonzera kuomesa kunetseka kubva muLake District.
Iyi ndiyo yakave mhedziso yakasvikwa nevamwe vaongorori kubva kuLaval University, Wilfrid Laurier University, Brock University uye University of Waterloo mune ongororo yakaburitswa mavhiki mashoma apfuura papeji repamutemo rejenali resainzi Geophysical Research Letters. Kufumura humwe humwe humbowo, kana izvo zvisati zvakwana iko pachena kweiyo kupisa kwepasi pose.
Vatsvakurudzi vakasvika pamhedziso iyi mushure mekudzidza madhamu makumi manomwe padhuze neOld Crow, Yukon uye Churchill, Manitoba, Canada. Mazhinji emakungwa akafundwa aive asingasviki mita imwe yakadzika. Sekureva kweongororo dzakaitwa, inopfuura hafu yemakungwa ari munzvimbo dzakapetana uye dzakakomberedzwa nemakwenzi, anoratidza zviratidzo zvekushushikana.
Iri dambudziko rinouya kunyanya kubva pakuderera kwemvura kunouya kubva ku nyungudika. Semuenzaniso, kubva muna 2010 kusvika 2012 avhareji yemvura yekunaya muchando muChurchil yakadzikira ne76 mm zvichienzaniswa neavhareji akanyorwa pakati pa1971 na2000. Kuomeswa kwemamwe madziva, ayo akazoonekwa neziso rekushama kekutanga muna 2010, akatonyanya yakataurwa muna 2013.
Kune aya marudzi emakungwa, kunaya kwechimiro kwechando kunomiririra pakati pe30% ne50% yemvura yegore negore. Rudzi rwekuomesa rwakacherechedzwa nevatsvakurudzi rwanga rusati rwamboitika mumakore 200 apfuura Zvakare, iyo isotopic ongororo yakaitwa pane iyo phytoplankton inoramba yakaunganidzwa mumabhedha edziva inoratidza kuti madziva akachengetedza iyo aquiferi chiyero kwemakore mazana maviri.
Kudzikama uku kwakangoerekana kwakanganiswa makore mashoma apfuura. Kana maitiro echando akaoma uye echando ane chando chidiki akaenderera, sezvakafanotaurwa nemamiriro ekunze, mazhinji emakungwa asina kudzika e-arctic anogona kupedzisira aoma zvachose. Zvakaoma kufungidzira mhedzisiro yese yekurasikirwa nenzvimbo iyi, asi ichokwadi kuti mhedzisiro yezvakatipoteredza ingave yakakosha.
Snowmelt ndiyo sosi yakakosha yemvura kumadhamu mazhinji epasi pearctic, asi mamodheru emamiriro ekunze anofungidzira kuti kunaya kwechando kuchadzikira mune mamwe matunhu, zviine mhedzisiro yezvakatipoteredza. Muchinyorwa chino, matatu ma parameter anoshandiswa senge isotopic dhata remvura yegungwa pamwe chete, gradients yevhu yepasi pevhu (kubva kuvhurika tundra kusvika kumasango akavharwa) uye nzvimbo yepamusoro yekuona makungwa ari panjodzi yekudonha pasi pemamiriro e yakadzika meltwater inomhanya munzvimbo mbiri dzepasi pearctic - Iyo Old Crow Plains, Yukon, uye Hudson Bay Shoals, Manitoba, Canada.
Madziva ari mukati memakungwa uye munzvimbo dzakashama dzematundra anoratidza muripo pakati pealeoclimatic indicator zviyero zvemakungwa emvura okisijeni isotopu (-18O) pamusoro pemakamputa mazhinji esampuli, akaburitswa kubva kune cellulose yakawanikwa munzvimbo dzichangoburwa dzevhu. Uku kuripwa kunofungidzirwa kuti kune kwakanyanya kubuda kwemvura kwakafumiswa muna 18O iyo inopindura kune yakaderera kupfuura avhareji yemvura yechando kuyerera mumakore apfuura.
Zvinokosha kuziva kuti nyanza zhinji dzaive dzave pedyo nekupedzisa kuoma mukati mekati kati mezhizha ra2010, raiteera nguva yechando ine kunaya kwakadzika muchimiro chechando. Kubva pane paleoimnological zvinyorwa zvemhando idzi dzemakungwa, mamiriro akaomesesa a2010 anogona kunge asina kuitika mumakore mazana maviri apfuura. Iyi mhedziso inodyisa kunetsekana kwekuti kuderera kwekuyerera kubva mukunaya kwechando kunotungamira mukuwomesa kwakadzika kubva mumakungwa asina kudzika murudzi urwu rwepasi.
Mamwe Mashoko: WWF ine hanya nekukasira uye kusimba kwekuchinja kwemamiriro ekunze, Chando cheArctic chinonyangarika pamwero werekodhi, Iko kunetseka kutsakatika kwechando muArctic
Source: Geophysical Research Research