The effects of salinity on growth and survival of mangrove seedlings changes with age

Kodikara, Kodikara Arachchilage Sunanda; Jayatissa, Loku Pullukuttige; Huxham, Mark; Dahdouh-Guebas, Farid; Koedam, Nico

Abstract

Six-wide ranging mangrove species, Rhizophora apiculata, R. mucronata, Avicennia marina, A. officinalis, Bruguiera gymnorrhiza, and B. sexangula, were selected to study the growth and survival of seedlings under three contrasting salinity treatments over a 30-week period: low (3-5psu), moderate (15-17psu) and high (33-36psu). Seedlings grown under high salinity exhibited significantly lower performance (p < 0.05) in survival rates, cumulative shoot height, mean growth rates, mean total leaf area, and mean dry weight, compared to those under low and moderate salinity regimes. Th e low salinity treatment provided the best conditions for initial establishment and growth of the seedlings of all species until 15-20 weeks of age. However, the same seedlings showed better performance under moderate salinity after 15-20 weeks of age (shift in optimal salinity), implying that adaptation to salt and physiological needs of mangrove seedlings varies with age. These results have practical implications of use in raising up mangrove nurse species for planting since it indicates that seedlings should get low salinity water until four to five months of age and then moderately saline water, in order to achieve maximum growth and survival.

Citation

Kodikara, K. A. S., Jayatissa, L. P., Huxham, M., Dahdouh-Guebas, F., & Koedam, N. (2018). The effects of salinity on growth and survival of mangrove seedlings changes with age. Acta botânica brasilica Sociedade Botânica do Brasil, 32(1), 37-46. https://doi.org/10.1590/0102-33062017abb0100

• Journal Article Type: Article
• Acceptance Date: Aug 23, 2017
• Online Publication Date: Nov 6, 2017
• Publication Date: 2018-01
• Deposit Date: Oct 25, 2017
• Publicly Available Date: Jul 17, 2019
• Journal: Acta Botanica Brasilica
• Print ISSN: 1677-941X
• Electronic ISSN: 0102-3306
• Peer Reviewed: Peer Reviewed
• Volume: 32
• Issue: 1
• Pages: 37-46
• DOI: https://doi.org/10.1590/0102-33062017abb0100
• Keywords: Avicennia; Bruguiera; early growth; Mangroves; nursery; planting; Rhizophora; salinity; Sri Lanka; survival
• Public URL: http://researchrepository.napier.ac.uk/Output/1001557
• Additional Information: This work described in this paper was supported by the VLIR-UOS-funded “Green Dyke project” (Flemish Interuniversity Council – University Development Cooperation) and University Grant Commission, Sri Lanka (UGC/DRIC/PG/2014AUG/RUH/02). We would also like to thank Dr. M.P. Kumara for his assistance in this study.