Genetic recolonization of mangrove: genetic diversity still increasing in the Mekong Delta 30 years after Agent Orange

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 390:129-135 (2009) - DOI: https://doi.org/10.3354/meps08183 Genetic recolonization of mangrove: genetic diversity still increasing in the Mekong Delta 30 years after Agent Orange Sophie Arnaud-Haond1,2,*, Carlos M. Duarte3, Sara Teixeira1, Sonia Isabel Massa1, Jorge Terrados3, Nguyen Hong Tri4,5, Phan Nguyen Hong4,5, Ester A. Serrão1 1CCMAR - CIMAR, Center of Marine Sciences, Universidade do Algarve, Gambelas, 8005-139, Faro, Portugal 2IFREMER, Centre de Brest, BP70, 29280 Plouzané, France 3Instituto Mediterraneo de Estudios Avanzados, CSIC-Universitat de les Illes Balears, C/ Miquel Marques 21, 07190 Esporles, Mallorca, Spain 4Mangrove Ecosystem Research Division (MERD), Vietnam National University, N°7 Ngo 115 Nguyen Khuyen St, Van Mieu, Hanoi, Vietnam 5Present address: Center for Environmental Research and Education (CERE), Hanoi University of Education, 136 Xuan thuy, Quan Hoa, Cau Giay, Hanoi, Vietnam *Email: sarnaud@ifremer.fr ABSTRACT: The widespread use of Agent Orange (a mixture of phenoxyl herbicides) over Southern Vietnam by US Forces led to the decimation of mangrove forests in the Mekong Delta. Mangrove trees Avicennia alba were sampled across the Mekong Delta; their age was assessed using models based on internode growth and samples were genotyped for 6 microsatellite loci. The evolution of genetic diversity over time elapsed since local extinction was reconstructed and compared with the genetic diversity of an unaffected population from Thailand. The results show that genetic diversity of the A. alba population is still increasing in the Mekong Delta 3 decades after the end of the Vietnam War, but is reaching an asymptotic level that is comparable to the adjacent non-affected population of Thailand. This might be a sign of genetic recovery, but may also reveal a limitation, either of genetic enrichment due to current predominance of auto-recruitment or of demographic increase due to intraspecific competition in this pioneer species. In any case, these results, although encouraging, demonstrate that genetic recovery after complete or almost complete population depletion continues over a longer time-scale than apparent demographic recovery. KEY WORDS: Recolonization genetics · Genetic recovery · Demographic recovery · Local extinction · Mangrove · Deforestation · Agent Orange Full text in pdf format PreviousNextCite this article as: Arnaud-Haond S, Duarte CM, Teixeira S, Massa SI and others (2009) Genetic recolonization of mangrove: genetic diversity still increasing in the Mekong Delta 30 years after Agent Orange. Mar Ecol Prog Ser 390:129-135. https://doi.org/10.3354/meps08183 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 390. Online publication date: September 18, 2009 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2009 Inter-Research.