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Can the new
recorded species be established in Burullus protected area:
A Ramsar site in Egypt
Yassin Mohamed Al-Sodany
Botany Department, Faculty of Science, Kafr El-Sheikh
University, Kafr El-Sheikh, Egypt. E-mail:
yalsodany@yahoo.com
. Tel.: 0020124385751.
Accepted 3 July, 2009 |
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Invasions by alien plant species are causing major
conservation problems in many regions of the world and are
viewed as an important component of human caused global
change. Lake Burullus (one of the protected areas and RAMSAR
site in Egypt) and its surroundings are subjected to
ecological constraints that relate to excessive use of
resources such as the construction of an International
Highway that runs along its sand bar. This paper aims in
evaluating the extent of the new invaded species in Burullus
Wetland and in studying the demography of the populations of
these species in terms of size structure, natality,
mortality, survival and demographic flux. Such type of study
helps in understanding the invasive ability of these species
in this area, which consequently helps in managing their
populations in the wetland. The questions addressed are: 1-
How many invaded plant species does Burullus Wetland have?
2- What is the Egyptian geographical origin of these
species? 3- Which population can be established and which
can be excluded in this area? and 4- Which population can't
be adapted? Thirteen perennial species were recoded in the
last 8 years: four were recoded for the first time in 2001
at Kassarah site and were established up till 2008 (Convolvulus
lanatus, Artemisia monosperma, Cornulaca monacantha
and Panicum turgidum), Nine species were recoded in
2006 at Kassarah and along International Highway; five of
them were established themselves up till 2008 (Thymelaea
hirsuta, Astragalus spinosus, Deverra tortuosa,
Zygophyllum coccineum and Retama raetam). Four
species can't be adapted in this region (Stipa capensis
in Kassarah site and Salsola tetrandra, Astragalus Siberi
and Zilla spinosa along International Highway). The
yearly variation in the demographic variables indicated that
2006 and 2008 had the maximum natality for all species,
while 2004 had the maximum mortality. The size distribution
at the end of the monitoring period indicated that the
invaded species may approximate J-shape, stationary or
inverse J-shaped size distributions. The number of
individuals along the International Highway decreased from
2006 to 2008, but the individual dimensions (That is, size)
increased for some species and decreased for another.
The present study suggested that, carrying out long-term
studies and monitoring on the vegetation and the invaded
species of the International Highway and its surrounding
habitats, especially Kassarah site (That is, conservation of
biodiversity).
Key words: Invasive plants, demography, natality, mortality, size
distribution. |
