Quantitative Phytosociological Study of Some Halophytes and Xerophytes in Egypt

Document Type : Original Article

Author

Botany Department, Faculty of Science, Mansoura University, Mansoura, Egypt

Abstract

The present study was carried out on some halophytes and xerophytes in the Deltaic Mediterranean
coastal salt marshes, desert of north and south Sinai and the northern part of the Red Sea coastal desert by
studying their distribution and response to prevailing environmental factors. Vegetation and soil were
sampled in 56 stands representing different saline and xeric habitat types. Relative values of frequency,
density and cover were determined for each perennial species and were then added to provide an estimate
of its importance value. Two Way Indicator Species Analysis (TWINSPAN) classified the stands into
four defined vegetation groups using importance values of plant species. Detrended Correspondence
Analysis (DCA) and Canonical Correspondence Analysis (CCA) were used to study species-environment
relationships. The vegetation groups obtained by TWINSPAN classification were distinguishable and had
a clear pattern of segregation on the ordination planes. Moisture content, porosity, sand fraction, sodium
cation, electrical conductivity (EC) and chloride contents were the most important soil factors for the
distribution of halophytic species. While the contents of calcium carbonate, magnesium and calcium
cations, total nitrogen, silt and clay fractions and the soil reaction (pH) were the most effective soil
factors affecting the distribution of xerophytic species.

Keywords