Relict Maquis Trees

פורסם: October 17th, 2010 | עודכן: 14/01/15

Trees are found in huge desert areas mostly near wadis (dry water-courses), where large amounts of water accumulate in the alluvium during winter floods. Most of the [Acacia] trees in wadis utilize water accumulated in the alluvium (Fig. 3.1.42). Mediterranean trees grow in large soil pockets and below the outcrops of smooth-faced rocks. [Juniperus phoenicea] grows all around the Mediterranean Sea (Fig. 3.1.43). Its adult branches resemble those of [Cupressus sempervirens] (cypress tree). However, the juniper cones resemble brownish-red berries when ripe (Figs. 3.1.44, 3.1.45). In the moist parts of its distribution area, e.g. in Greece, north-east of Patras, in maquis with 400-600 mm mean annual rainfall, [“Juniperus phoenicea” J. phoenicea] develops as a tree or shrub (Fig. 3.1.46, 3.1.47). In moister areas (Fig. 3.1.48) junipers grow on cliffs where their rhizosphere is rather limited in size and the tree functions as a xerophyte. In N Sinai it grows in large soil pockets, below the outcrops of smooth-faced rocks, and in wadis with these smooth rocks in their drainage area (Figs. 3.1.49-3.1.51). It may reach an age of several hundred years (Fig. 3.1.50). In Edom it grows in soil pockets of limestone and hard sandstone (Figs. 3.1.52-3.1.55). Its roots penetrate fissures in the rock (Fig. 3.1.55).

In addition, it also grows in Edom on soft sandstone covered by alluvium-colluvium. Such slopes are seen in mountainous terrain where thick layers of fissured limestone overlie the soft sandstone (Figs. 3.1.52, 3.1.56). A preliminary working hypothesis is that rain water percolating through the fissured limestone accumulates in the clayey layers inter-bedded with the sandstone, at a depth where it is available for tree utilization. There are places in Edom where dripping springs are found in such soft substratum. Wherever J. phoenicea is found, it propagates by way of seed germination (Fig. 3.1.57). Its seedlings establish themselves in appropriate microhabitats in the vicinity of their parents. Looking at the range of growth of [“Juniperus phoenicea” J. phoenicea] in the Middle East (Fig. 3.1.58), it is found in folded mountains of N Sinai and the mountain slopes of Edom. No spontaneous living trees of this species are found in Israel; however, charcoal fossils of trunks, dating from 9000 and 34000 years ago, were found in archaeological digs in the Negev.

Fig. 3.1.42: A pseudo-savannah of Acacia raddiana in a dry water-course at low elevation in S. Sinai.

Fig. 3.1.43: Distribution map of Juniperus phoenicea.

Fig. 3.1.44: Juniperus phoenicea branches resemble those of Cupressus, but the small cones look like fruits.

Fig. 3.1.45: Juniperus phoenicea branches.

Fig. 3.1.46: Slopes southwest of Delphi, Greece, with Juniperus phoenicea and Olea europaea dominating the woodland.

Fig. 3.1.47: Eastern Crete where Juniperus phoenicea shrubs are accompanied by Sarcopoterium and Coridothymus.

Fig. 3.1.48: Cliffs near Montpellier, southern France, where Juniperus phoenicea is dominant.

Fig. 3.1.49: Gebel Halal in N. Sinai (P=80-100 mm), where Juniperus phoenicea trees survive in smooth-faced rocks. They penetrated the desert in a moist period more than 40,000 years ago. A branch of the marked tree shows 865 annual rings.

Fig. 3.1.50: A Juniperus phoenicea branch, 865 years old; it seems to be the oldest tree recorded so far in the Middle East.

Fig. 3.1.51: Juniper trees in a wadi draining the large rocky surface attain considerable size, because they are not cut down for fire-wood: the burning wood “explodes” creating sparks that can burn the Bedouin tent.

Fig. 3.1.52: Petra area and slopes of the Jordanian plateau. The moisture regime of the junipers in the two habitats is assumed to be different. 1. Juniperus phoenicea in crevices of hard sandstone, 2. Juniperus phoenicea on a soft sandstone slope.

Fig. 3.1.53: Juniper trees in sandstone crevices, southern Dana Nature Reserve, Jordan.

Fig. 3.1.54: A holy, protected Juniperus phoenicea near Petra (left); Juniper trees in sandstone crevices (right).

Fig. 3.1.55: Juniperus phoenicea in crevices of hard sandstone and on a soft sandstone slope. Dana Nature Reserve, Jordan.

Fig. 3.1.56: Juniper tree in sandstone with roots penetrating the sandstone rock.

Fig. 3.1.57: A seedling of Juniperus phoenicea with two types of leaves.

Fig. 3.1.58: The “archipelago” of hard rock-islands in desert areas of the Middle East and Juniperus phoenicea distribution.