Effects of flow alteration on Apple‐ring Acacia (Faidherbia albida) stands, Middle Zambezi floodplains, Zimbabwe. Issue 5 (21st August 2014)

• Record Type: Journal Article
• Authors: Gope, Evelyn T.; Sass‐Klaassen, Ute G. W.; Irvine, Kenneth; Beevers, Lindsay; Hes, Edwin M. A.; Boudell, Jere A.; Dixon, Mark D.; Rood, Stewart B.; Stromberg, Juliet C.
• Is Part Of: Ecohydrology. Volume 8:Issue 5(2015)
• Page Start: 922
• Page End: 934
• Publication Date: 2014-08-21
• Subjects: Ecohydrology -- Periodicals; Hydrology -- Periodicals; Water -- Environmental aspects -- Periodicals; 577.6
• DOI: 10.1002/eco.1541
• Languages: English
• ISSNs: 1936-0584

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <p>The impounding of the Zambezi River by Kariba dam has regulated the river discharge of the Middle Zambezi river. This has been implicated in the failure of regeneration of <italic>Faidherbia albida</italic> in the downstream flood plain. This study aimed (1) to assess the effect of the altered flow regime of the river on the establishment and growth of <italic>F. albida</italic> on the Middle Zambezi floodplain and islands and (2) to test the potential of dendrochronology in detecting the age and long‐term growth rates of <italic>F. albida</italic> in response to flow regime.</p> <p>Results indicated an uneven age distribution of <italic>F. albida</italic> stands on relatively 'new islands', dominated by young trees, while the floodplain and the 'old island' exhibited an even‐aged stand but with a lack of regeneration, and a dying‐off of older trees. The lack of <italic>F. albida</italic> establishment on the floodplain was linked to the decreased occurrence of flooding events, associated with a decrease in alluvial deposits, soil moisture and groundwater recharge. These effects may be enhanced by impact from browsers on regeneration of trees. Tree‐ring analyses revealed the presence of distinct annual growth rings in <italic>F. albida</italic> and the applicability of dendrochronology for estimating <italic>F. albida</italic> population dynamics<italic>.</italic> The trees on the 'new islands' are younger and grow faster than those on the floodplain. Lack of competition and possible favourable moisture conditions suggest beneficial conditions for establishment and growth of the trees on the islands. Copyright © 2014 John Wiley & Sons, Ltd.</p> </abstract>