title: Differences in root aeration, iron plaque formation and waterlogging tolerance in six mangroves along a continues tidal gradient.
abstract: Mangrove is a special coastal forest along tropical and subtropical intertidal shores. However, how mangroves adapt to tidal flooding and the mechanisms involved in mangrove zonation are still poorly understood. In this study, a pot trial with different tide treatments was conducted to investigate the differences in root anatomy, porosity, radial oxygen loss, iron plaque formation and waterlogging tolerance among six mangroves along a continuous tidal gradient. The index of waterlogging tolerance illustrated that Sonneratia apetala possessed the highest index, followed by Aeguceras corniculatum/Kandelia, Rhizophora stylosa, Heritiera littorlis and Thespesia populnea. Waterlogging tolerances of the mangroves were found to be positively correlated with their root porosity, radial oxygen loss and iron plaque formation. Waterlogging-sensitive species such as landward semi-mangroves exhibited small root porosity and ROL, while waterlogging-tolerant species such as seaward pioneer and rhizophoraceous mangroves exhibited extensive porosity, ROL and iron plaque formation. Nevertheless, grater root porosity and iron plaque formation were detected in permanent waterlogged plants when compared to drained plants. In conclusion, The present study proposes a structural adaptive strategy to tidal flooding in mangroves, such that the mangroves with higher root porosity, ROL and iron plaque appeared to exhibit higher waterlogging tolerance and adaptability in anaerobic foreshores.
authors.affiliation: State Key Laboratory of Tropical Oceanography and Daya Bay Marine Biology Research Station, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Cheng
authors.affiliation: State Key Laboratory of Tropical Oceanography and Daya Bay Marine Biology Research Station, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China. yswang@scsio.ac.cn.
authors.forename: You-Shao
authors.initials: YS
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Tropical Oceanography and Daya Bay Marine Biology Research Station, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China.
authors.forename: Jiao
authors.initials: J
authors.lastname: Fei
authors.affiliation: State Key Laboratory of Tropical Oceanography and Daya Bay Marine Biology Research Station, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China.
authors.forename: Zhao-Yu
authors.initials: ZY
authors.lastname: Jiang
authors.affiliation: State Key Laboratory for Bio-control, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510006, China.
authors.forename: Zhi-Hong
authors.initials: ZH
authors.lastname: Ye
mesh_terms: D002681:China; D007501:Iron / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D018517:Plant Roots / Q000033:anatomy & histology / Q000502:physiology*; D016062:Porosity; D013045:Species Specificity; D055871:Tidal Waves; D014197:Trees / Q000033:anatomy & histology / Q000502:physiology*; D014867:Water / Q000502:physiology*; D053833:Wetlands
chemical_list: D014867:Water; D007501:Iron; D010100:Oxygen
keywords: Iron plaque; Mangrove; Root aeration; Waterlogging