Vegetation Changes in the Long Abandoned Farms in Qatar

Abstract

An attempt was made in this study to investigate the changes that occur in vegetation cover in the totally abandoned farms in Qatar. An effort was also made to compare the vegetation communities found in the abandoned farms with those in the uncultivated "natural" depressions. The following hypothesis was formulated : In the long abandoned farms vegetation is gradually recovering to the original pre-cultivation communities due to the steady decrease in soil salinity. To test the above hypothesis soils and vegetation of both the uncultivated "natural" depressions and the long abandoned farms were sampled and analysed. Soil samples were taken for chemical analysis and their salinity content was determined. Empirical sampling methods of the vegetation were applied. Species frequency and density were calculated, while the degree of species similarity was estimated by Kulezynski's (1937) formula for community coefficient given by Oosting (1956). It was found out that following total farm abandonment, the vegetation communities start to recover in a rather slow process. This recovery process is caused and at the same time paralleled by a steady decrease in soil salinity, as salts are washed away by rain water. Different vegetation communities as well as different species within the communities were found to be in different stages of recovery, i.e., secondary succession. Only few species from the original vegetation were encountered in some abandoned farms, while in the other end of the spectrum some totally abandoned farms have almost attained full recovery.