Oxygen din kwayoyin da ke narkar da ruwa ana kiransa narkar da iskar oxygen kuma yawanci ana yiwa alama D0. Adadin narkar da iskar oxygen a cikin ruwan saman shine 5-10mg / L. Lokacin da aka sami iska mai ƙarfi da raƙuman ruwa, narkar da iskar oxygen a cikin ruwa na iya kaiwa 14mg/L. Narkar da jikewar iskar oxygen = narkar da iskar oxygen Ƙimar aunawa / abun ciki jikewa na narkar da iskar oxygen a ƙarƙashin yanayin da aka auna * 100%, wato 90% da sama, ƙimar da aka auna yana sama da 7.5mg/L, kuma mafi ƙarancin shine 2mg/L.
Ruwan da ba shi da iskar oxygen zai bi ta cikin shuka kuma ya cire iskar oxygen daga tushen tsarin, haka ma, zai rage iskar oxygen a cikin ƙasa. Dukan tsire-tsire masu lafiya da flora na ƙasa mai lafiya suna buƙatar iskar oxygen a cikin waɗannan sassa biyu.
Rashin narkar da iskar oxygen a cikin ruwa kuma na iya haifar da wasu matsaloli. Alal misali, nematodes kamar ƙasa anoxic. Bayar da tsire-tsire tare da ƙarancin iskar oxygen zai haifar da su kusa da saman kuma a sauƙaƙe lalata tushen tsire-tsire.
Nazarin ya nuna cewa rage yawan narkar da iskar oxygen a cikin tushen tushen shuka zai rage ikon shukar don sha nitrogen da ruwa. Rashin iskar oxygen na iya cutar da tushen. A lokacin daidaitawa zuwa ƙananan adadin iskar oxygen narkar da, ƙwayar shuka ta canza. Rashin iskar oxygen a cikin shuka ana kiransa hypoxia na ciki. Ɗaya daga cikin sakamakon shine sucrose yana raguwa, kuma tsire-tsire suna motsawa zuwa hanyoyin ceton makamashi don rama rashin iskar oxygen.
Photosynthesis na phytoplankton shine tushen farko na iskar oxygen a cikin tafki, yawanci yana lissafin 56% -80% na tushen iskar oxygen; sauran suna fitowa ne daga iskar da ke kadawa ta yadda iskar oxygen da ke cikin iska ta narke cikin ruwa kai tsaye. Amfanin 12-14mg/L
Heilongjiang: Wani yanki mai fadin murabba'in murabba'in mita 600 na tafkin basking zai inganta zafin ruwa da digiri 3 zuwa 4 kuma ya kara yawan samar da hatsi da kashi 6%.