| Popis: |
The population structure, growth rates and spacing of tamarisk were measured in the north-east corner of Sebkhet Kelbia, a shallow, evaporative lake in central Tunisia. The density of stems was 7·0/m2 with a mean age of six years and a range from three to eight years. All the bushes in the sample were established after the last inundation in 1969 with 74 per cent post-dating the 1973 flood. The analysis of growth rates suggests a relatively uniform environment since these events although the lake is probably becoming increasingly saline. The age distribution and height characteristics of the tamarisk present an unusual structure for a natural population. The age distribution shows no successful regeneration in the last three years although seedlings were present at the time of survey. The tamarisk stands were of uniform height and possibly indicate the growth potential of the site. The basal area relative growth rates were found to be inversely related to the number of stems per unit area. Vigour (width of outermost annual rings) was similarly a function of density. |
