Rashin lafiya na Tekun Baltic

**Tekun Baltic hypoxia** yana nufin ƙananan matakan oxygen a cikin ruwa na ƙasa, wanda kuma aka sani da hypoxia, yana faruwa akai-akai a cikin Tekun Baltic .   jimlar yanki na ƙasa an rufe shi da ruwan hypoxic tare da adadin iskar oxygen ƙasa da 2&nbsp;mg/L a cikin Tekun Baltic ya kai 49,000 km2 a cikin shekaru 40 da suka gabata. Babban dalilin hypoxia shine wuce gona da iri na abubuwan gina jiki daga ayyukan ɗan adam wanda ke haifar da furen algal . Furannin furanni suna nutsewa zuwa ƙasa kuma suna amfani da iskar oxygen don bazuwa a cikin sauri fiye da yadda za'a iya ƙara su cikin tsarin ta hanyar tsarin jiki na haɗuwa. Rashin iskar oxygen ( anoxia ) yana kashe kwayoyin halitta masu rai kuma yana haifar da matattun yankuna . 

## Dalilan da suka haifar
Saurin karuwa a cikin hypoxia a yankunan bakin teku a duniya saboda yawan abubuwan gina jiki na shuke-shuke, kamar nitrogen da phosphorus ta ayyukan ɗan adam. Tushen waɗannan abubuwan gina jiki sun haɗa da noma, datti, da kuma sanya nitrogen a cikin yanayi wanda ke dauke da mahadi daga ƙone burbushin burbushin halittu. Abinci yana motsa ci gaban algae wanda ke haifar da matsaloli tare da eutrophication. Algae ya nutse zuwa kasa kuma yayi amfani da iskar oxygen lokacin da suka lalace. Idan haɗuwa da ruwan da ke ƙasa yana da jinkiri, don haka ba a sabunta ajiyar iskar oxygen ba, hypoxia na iya faruwa.

## Bayyanawa
Ya zuwa shekara ta 2 jimlar yankin kasa da aka rufe da ruwa mai guba tare da iskar oxygen ƙasa da 2 MG / L a cikin Tekun Baltic ya kai kimanin kilomita 49,000 a cikin shekaru 40 da suka gabata. A cikin Tekun Baltic, shigar da ruwan gishiri daga Tekun Arewa ta hanyar Danish Straits yana da mahimmanci wajen tantance yankin hypoxia a kowace shekara. Denser, ruwan gishiri yana zuwa cikin Tekun Baltic kuma yana gudana tare da kasa. Kodayake manyan ruwan gishiri suna taimakawa wajen sabunta ruwan da ke ƙasa da kuma kara yawan iskar oxygen, ana amfani da sabon iskar oxygen da aka kara tare da ruwan gishiri da sauri don lalata kwayoyin halitta da ke cikin turɓaya. Ruwan gishiri mai yawa kuma yana rage haɗuwa da ruwan oxygen mara kyau tare da ruwan gishiri, ruwan sama mai sauƙi. Don haka, manyan wuraren hypoxia suna faruwa lokacin da ruwan gishiri ya zo cikin Tekun Baltic.&nbsp;

## Halin yanayin ƙasa
Ana amfani da tarihin ilimin ƙasa a cikin turɓaya, da farko bayyanar turɓaya mai laushi wanda ke faruwa ne kawai lokacin da yanayin hypoxic yake, don ƙayyade tarihin lokacin yanayin iskar oxygen.

Yanayin hypoxic ya zama ruwan dare a lokacin ci gaban Tekun Baltic na farko da ake kira Tekun Mastogloia da Tekun Littorina wanda ya fara kusan shekaru 8,000 Kafin Yanzu har zuwa 4,000 BP. Hypoxia ya ɓace kusan kusan shekaru 2,000, ya bayyana a karo na biyu kafin Lokacin Warm na Tsakiya a kusa da 1 AD har zuwa 1200 AD. Tekun Baltic ya sake zama hypoxic a kusa da 1900 AD kuma ya kasance hypoxic na shekaru 100 da suka gabata. 

Ana muhawara game da abubuwan da ke haifar da lokuta daban-daban na hypoxia ta hanyar kimiyya, amma an yi imanin cewa ya haifar da babban salinity, yanayi da tasirin ɗan adam.

## Tasirin
Rashin iskar oxygen a cikin ruwan kasa yana canza nau'ikan kwayoyin da ke zaune a kasa. Dabbobi suna canzawa daga dabbobi masu rai, masu zurfi, masu saurin girma zuwa nau'ikan da ke zaune a saman laka. Suna da ƙananan kuma suna girma da sauri, kuma suna iya jure ƙananan iskar oxygen. Lokacin da yawan iskar oxygen ya yi ƙasa sosai ƙwayoyin cuta da ƙwayoyin ƙwayoyin halitta ne kawai zasu iya rayuwa, wuraren da suka mutu sun samo asali. A cikin Tekun Baltic, ƙananan iskar oxygen kuma suna rage ikon cod don haifar da ruwa mai zurfi. Tsire-tsire na cod yana buƙatar babban salinity da babban iskar oxygen don ƙwayoyin ƙwayoyin cuta don haɓaka, yanayin da ba su da yawa a cikin Tekun Baltic a yau.  Rashin iskar oxygen kuma yana ƙara sakin phosphorus daga ƙasa. Yawan phosphorus a cikin ruwa na sama da rashin nitrogen yana motsa ci gaban cyanobacteria. Lokacin da cyanobacteria suka mutu kuma suka nutse zuwa kasa suna cinye iskar oxygen wanda ke haifar da ƙarin hypoxia kuma ana fitar da ƙarin phosphorus daga ƙasa. Wannan tsari yana haifar da mummunan zagaye na eutrophication wanda ke taimakawa wajen kiyaye kansa.

## Magani
Kasashen da ke kewaye da Tekun Baltic sun kafa Hukumar Kare Muhalli ta HELCOM Baltic don karewa da inganta lafiyar muhalli ta Tekun Baltic. A cikin shekara ta 2007, kasashe membobin sun amince da shirin Sea Action na Baltic don rage abubuwan gina jiki. Saboda jama'a da kafofin watsa labarai sun yi takaici saboda rashin ci gaba wajen inganta yanayin muhalli na Tekun Baltic, an yi kira ga manyan hanyoyin injiniya don ƙara iskar oxygen a cikin ruwan kasa da kuma dawo da rayuwa zuwa yankunan da suka mutu. Wani kwamitin kasa da kasa ya kimanta ra'ayoyi daban-daban  kuma ya zo ga ƙarshe cewa manyan hanyoyin injiniya ba su iya ƙara iskar oxygen ga manyan wuraren da suka mutu a cikin Tekun Baltic ba tare da canza tsarin halittu na Tekun Baltic gaba ɗaya ba. Mafi kyawun mafita na dogon lokaci shine aiwatar da manufofi da matakan rage nauyin abubuwan gina jiki zuwa Tekun Baltic.

## Manazarta