铁元素限制海藻生长可能会阻碍海洋造林。

Iron limitation of kelp growth may prevent ocean afforestation.

机构信息

Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS, 7001, Australia.

Australian Antarctic Program Partnership (AAPP), Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS, Australia.

出版信息

Commun Biol. 2023 Jun 6;6(1):607. doi: 10.1038/s42003-023-04962-4.

DOI:10.1038/s42003-023-04962-4

PMID:37280329

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC10244339/

Abstract

Carbon dioxide removal (CDR) and emissions reduction are essential to alleviate climate change. Ocean macroalgal afforestation (OMA) is a CDR method already undergoing field trials where nearshore kelps, on rafts, are purposefully grown offshore at scale. Dissolved iron (dFe) supply often limits oceanic phytoplankton growth, however this potentially rate-limiting factor is being overlooked in OMA discussions. Here, we determine the limiting dFe concentrations for growth and key physiological functions of a representative kelp species, Macrocystis pyrifera, considered as a promising candidate for OMA. dFe additions to oceanic seawater ranging 0.01-20.2 nM Fe' ‒ Fe' being the sum of dissolved inorganic Fe(III) species ‒ result in impaired physiological functions and kelp mortality. Kelp growth cannot be sustained at oceanic dFe concentrations, which are 1000-fold lower than required by M. pyrifera. OMA may require additional perturbation of offshore waters via dFe fertilisation.

摘要

去除二氧化碳（CDR）和减少排放对于缓解气候变化至关重要。海洋大型海藻造林（OMA）是一种已经在进行野外试验的 CDR 方法，即将近岸海带放在筏子上，有目的地在近海大规模种植。然而，溶解铁（dFe）供应通常限制了海洋浮游植物的生长，但这一潜在的限速因素在 OMA 的讨论中被忽视了。在这里，我们确定了一种有前途的 OMA 候选物种——巨藻（Macrocystis pyrifera）生长和关键生理功能的限制 dFe 浓度。向海洋海水中添加范围为 0.01-20.2nM 的 dFe——Fe'表示溶解无机 Fe(III)物种的总和——会导致生理功能受损和海带死亡。在海洋 dFe 浓度下，海带无法生长，而这一浓度比巨藻所需的浓度低 1000 倍。OMA 可能需要通过 dFe 施肥来进一步干扰近海水域。