Shayarot Ridge (Continued)

פורסם: December 18th, 2011 | עודכן: 14/01/15

A special growth in the spring of 2011 was that of [Zilla spinosa] (Figs. 6.1.33-6.1.35). Many shrubs continued to grow during the rainless year, using the resources of previous years, and reached an extraordinary size. A similar situation was seen in other parts of the southern Negev.

Fig.6.1.33: Zilla spinosa flourishing

Fig.6.1.34: Zilla spinosa flowering

Fig.6.1.35: Anastatica hierochuntica with remnants of a plant from previous years and young, blooming individuals. The individuals size reflects the local water regime

[Anastatica hierochuntica]

Being one of the Saharo-Arabian species, this species has a unique means of survival. It is one of the few lignified annuals on earth. The plant stores its seeds in efficiently closed fruits and spreads them whenever there is a wealth of rains sufficient for germination, growth, flowering and fruiting. Even if the offspring die, there are plenty of closed fruits on the old plants containing seeds that may develop in good, rainy years to come. In photographs from 1994 (Figs. 6.1.36,6.1.37) a carpet of this plant can be seen, with millions of individuals. The same area in the dry year 2011 (Figs.6.1.38, 6.1.39) looks ready for the next unpredictable rainy year. The plant is fully adapted to unpredictable climatic events in the area of its growth.

Fig.6.1.36: A field of Anastatica hierochuntica on fine-grained soil in Biq’at ‘Uvda

Fig.6.1.37: A field of Anastatica hierochuntica blooming in 1991

Fig.6.1.38: A field of Anastatica hierochuntica in the spring of 2011 – not even one green seedling was found in Biq’at ‘Uvda

Fig.6.1.39: Plants of Anastatica hierochuntica ready for the next rain

List of plants found in Biq’at ‘Uvda and Shayarot Ridge

In the data base list of plants that I have been compiling for the last 40 years, are data on plants that I see in the field. The listing units are 5 X 5 km squares. All plant species found in the entire square are listed as if found in the center of the 25 km2 square. 200 species are present in the eight squares of Biq’at ‘Uvda and the Shayarot Ridge. Included in this list are 10 species that grow in the irrigated ornamental plots of the airport; these plants cannot survive in the natural conditions prevailing in Biq’at ‘Uvda and the Shayarot Ridge. The quantitative relations according to growth forms in the list are: annuals = 46.3%; geophytes = 3.2%; perennial herbs = 11.2%; semi-shrubs = 33.7%; shrubs = 3.7%; trees = 2.1%.

Bibliography

Danin, A. 1983. Desert Vegetation of Israel and Sinai. Cana, Jerusalem. 148 pp.
Danin, A. and Orshan, G. (eds.) 1999. Vegetation of Israel. I. Desert and coastal vegetation. Backhuys, Leiden, 341 pp.
Lipkin, J. 1971. Vegetation of the Southern Negev. PhD thesis, the Hebrew University of Jerusalem (in Hebrew with an English abstract).
Rudich, D. and Danin, A. 1978. The vegetation of the Hazeva area, Israel. Israel J. Bot. 27: 160 176.