Relict Geophytes

פורסם: October 3rd, 2010 | עודכן: 14/01/15

There are a few typical Mediterranean geophytes confined to smooth-faced rock-outcrops in the Middle-Eastern deserts. They are assumed to have arrived in periods of moister climate. The boundary of the Mediterranean territory extended south of its present day boundary. In soil pockets (Fig. 3.1.36) of smooth rock outcrops [Narcissus tazetta] continues to grow and to reproduce. All around the Mediterranean Sea [“Narcissus tazetta” N. tazetta] grows in deep wet clayey soil (Fig. 3.1.37) or in rock crevices and soil pockets of Mediterranean cliffs (Fig. 3.1.38). [Sternbergia clusiana] is a plant growing in large patches in the Mediterranean region (Fig. 3.1.39). It is found as a relict in the deserts of Israel and Jordan (Fig. 3.1.40). The last two species disperse their seeds only a short distance. There is, however, a great distance between the desert populations and the Mediterranean populations. It is not known how the seeds may have been transported to these distant areas, but I assume they are relicts from a period when the climate was moister. At that time, the boundary of the Mediterranean territory extended much closer to the desert sites and reached the dispersal distance of each of the two species.
There are additional geophytes, such as [Astomaea seselifolium] (Fig. 3.1.41), which have a similar distribution area.

Fig. 3.1.36: A north-facing smooth-faced limestone outcrop supporting Narcissus tazetta. The Negev Highlands (P=100 mm).

Fig. 3.1.37: Narcissus tazetta in deep clayey soil (Grumusol) of the coastal plain (P=500 mm).

Fig. 3.1.38: Narcissus tazetta on the cliffs of Mt. Carmel (P=600 mm).

Fig. 3.1.39: Sternbergia clusiana in a semi-steppe batha (P=300 mm). It grows also in the Upper Galilee (P=1000 mm).

Fig. 3.1.40: Sternbergia clusiana in a soil pocket in a hard smooth-faced limestone outcrop covered with epilithic lichens (P=100 mm).

Fig. 3.1.41: Astomea seselifolium, a weed in wheat fields of the Mediterranean territory, confined to soil pockets in rocks of the Negev Highlands and the N. Sinai anticlines.