环境因子对瓦氏马尾藻吸收溶解性无机碳及提升海水pH的影响

The effects of environmental factors on dissolved inorganic carbon absorption and increasing pH abilities of Sargassum vachellianum

探讨了温度、光照强度以及氮、磷加富对瓦氏马尾藻(Sargassum vachellianum)溶解性无机碳(DIC)吸收及提升海水pH能力的影响。结果表明:(1)温度、光照强度对瓦氏马尾藻的DIC吸收速率及海水pH提升速率影响显著(P<0.05),在光照强度60μmol/(m2·s)、温度20℃条件下,瓦氏马尾藻对DIC吸收速率和海水pH提升速率最大,分别高达82.14μmol/(g·h)和0.138/(g·h),当环境条件低于或高于这一阈值,藻体对DIC吸收和海水pH提升能力均有不同程度的降低;(2)氮、磷加富能够显著提高瓦氏马尾藻DIC吸收及提升海水pH能力(P<0.05),高氮、磷(HNP)组藻体对DIC吸收及提升海水pH能力均显著高于低氮、磷(LNP)组(P<0.05),且N、P的添加对增加藻体吸收DIC及提升海水pH的能力具有促进作用。该研究为利用瓦氏马尾藻增养殖技术进行近岸富营养化及藻场退化海域生态修复及减缓海洋酸化提供了理论依据。

We studied the effects of different temperatures,light intensity,nitrogen（ N） and phosphorus（ P）on the absorption of dissolved inorganic carbon（ DIC） and pH-improving rate of Sargassum vachellianum. The results showed that： 1） Temperature and light intensity all had a significant effect on the DIC sequestration and pH-improving capability of S. vachellianum（ P〈0. 05）. S. vachellianum shows the highest DIC sequestration [82. 14 μmol/（ g · h） ]and pH-improving capability [0. 138/（ g · h） ]when cultured at 20℃ and at a light intensity of 60 μmol/（ m2·s）. When the environmental conditions are below or above this threshold,the DIC sequestration and pH-improving capability of S. vachellianum appeared different degree reduction. 2） N and P enrichment could dramatically increase the DIC sequestration and pH-improving capability of S. vachellianum（ P〈0. 05）. The HNP group had significantly higher DIC sequestration and pH-improving capability than that of LNP group（ P〈0. 05）,and the addition of N and P showed strong complementary effects on improving the DIC absorption and pH-improving rate of S. vachellianum. The results could provide theoretical basis for the bioremediation and acidification mitigation by S. vachellianum cultivation in coastal eutrophication waters.