Vegetation‐environment relations along water courses in the Nile Delta region

Abstract

The present study analyses the vegetation of canals and drains in the Nile Delta in relation to environmental factors. 30 clusters were generated by the TWINSPAN technique. A DC A (DECORANA) ordination revealed a moisture gradient, and, less clearly, a salinity and a fertility gradient. The resultant clusters were assigned to seven vegetation types arranged according to moisture preference as follows: Imperata cylindrica ‐ Desmostachya bipinnata, Phragmites australis, Panicum repens ‐ Cynodon dactylon, Echinochloa stagninum ‐ Polygonum salicifolium, Echinochloa stagninum, Eichhornia crassipes , and Ceratophyllum demersum‐Pótame geton crispas. Their species diversity is discussed in view of the disturbance and heterogeneity hypotheses.