Ana kiran iskar oxygen ta kwayoyin halitta da aka narkar a cikin ruwa da oxygen mai narkewa kuma yawanci ana yi mata lakabi da D0. Adadin iskar oxygen da aka narkar a cikin ruwan saman shine 5-10mg/L. Idan akwai iska mai ƙarfi da raƙuman ruwa, iskar oxygen da aka narkar a cikin ruwan zai iya kaiwa 14mg/L. Cikakken iskar oxygen da aka narkar = ƙimar da aka auna ta cikakken oxygen/ruwa oxygen da aka narkar a ƙarƙashin yanayin da aka auna * 100%, wato, 90% ko sama da haka, ƙimar da aka auna ta wuce 7.5 mg/L, kuma mafi ƙarancin shine 2 mg/L.
Ƙarancin iskar oxygenruwaZai ratsa ta cikin shuke-shuke ya kuma cire iskar oxygen daga tushen sa. Haka kuma, zai rage iskar oxygen a cikin ƙasa. Shuke-shuke masu lafiya da kuma shuke-shuken ƙasa masu lafiya suna buƙatar iskar oxygen a waɗannan sassa biyu.
Rashin iskar oxygen da ke narkewa a cikin ruwa shi ma yana iya haifar da wasu matsaloli. Misali, ƙwayoyin cuta suna son ƙasa mai guba. Ban ruwa ga shuke-shuke da ruwan da ba shi da iskar oxygen zai kusantar da su kusa da saman kuma ya lalata tushen shuke-shuken cikin sauƙi.
Bincike ya nuna cewa rage yawan iskar oxygen da ke narkewa a cikin yanayin tushen tsirrai zai rage ikon tsirrai na shan nitrogen da ruwa. Rashin iskar oxygen na iya lalata tushen. A cikin tsarin daidaitawa da ƙarancin yawan iskar oxygen da ke narkewa, metabolism na tsirrai ya canza. Hypoxia a cikin shukar ana kiransa hypoxia na ciki. Ɗaya daga cikin sakamakon shine lalacewar sucrose, kuma tsire-tsire suna komawa ga hanyoyin adana makamashi don rama rashin iskar oxygen.
Tsarin photosynthesis na phytoplankton shine babban tushen iskar oxygen a cikin tafkuna, wanda gabaɗaya ya kai kashi 56%-80% na tushen iskar oxygen; sauran kuma suna fitowa ne daga iskar da raƙuman ruwa, ta yadda iskar oxygen da ke cikin iska ke narkewa kai tsaye cikin ruwa.ruwa. Mai amfani 12-14mg/L
Heilongjiang: 600-square-mitaTanda mai tanning zai iya ƙara zafin ruwa da digiri 3 zuwa 4 kuma ya ƙara yawan samar da hatsi da kashi 6%.