Desert Wadis

Description

Site # 1: Wadi Qena Wadi Qena, together with Wadi Allaqi, are intimately connected to the history of the Nile. Before the consolidation of the Nile configuration as we see it now, flowing from the Sudan into Egypt, there were several rivers flowing from the Red Sea mountains, from east to west, following the upheaval of the Red Sea coast, ad the formation of the Great Rift Valley. This uplift, associated with northerly trending fissures and fractures, realigned the drainage, such as the Qena River flowed from north to south in what is now Wadi Qena. This Wadi became a watershed for rivers flowing from north to south. Wadi Allaqi was another large river that flowed south-westward, draining the southern Red Sea mountains, and those in north-eastern Sudan as well. These two large rivers fed the recently discovered “radar-imaged” rivers of southwest Egypt. Though these “radar imaged” rivers are old features – predating Man – the discovery of an Acheulian hand axe on the bank of one of these streams suggests that these rivers were active during Acheulian times. After the retreat of the Mediterranean Pliocene water from the Gulf occupying most of the present-day Nile Valley, rejuvenation of old rivers flowing east-west and north-south, took place. It was only during the Middle Pleistocene that the trapped Ethiopian and equatorial African waters breached the cataracts in northern Sudan, capturing many side rivers as they poured through Egypt, to become the real Nile. It took Man several hundred thousand years to migrate from the relatively safe desert wadis on both sides of the Nile to its banks. These migrations were associated with drastic climatic changes from tropical savanna to arid dry conditions. Modrn desertification started approximately 7800 years ago (Issawy 2002). Site # 2: Wadi Gemal Wadi Gemal is a fascinating unpolluted site on the Red Sea coast, south of Mersa Alam. Besides the magnificent scenery of palm groves on the sea shore, there are beautiful coral reefs, mangroves, and different kinds of animals and plants. The rocks exposed between the high mountain of the Pre-Cambrian basement complex in the west and the sea shore in the east, range in age between Cretaceous and Quaternary. The Wadi is rich in biodiversity, especially in the highest of its mountains, Gebel Hamata. Seagrass beds there are of special importance because they harbour sea cows, in addition to fish and lots of marine invertebrates. The Wadi Gemal Island situated at the proximity of the the Wadi delta is of special international importance as it serves as a breeding haven for both breeding and migratory birds and is one of the important breeding spots for sea turtles in the Egyptian Red Sea coasts. In addition, Prehistoric, Ptolemaic and Roman vestiges abound, as well as ancient emerald quarries, not to mention the uniqueness of the indigenous people there and their exceptional local traditions and culture. Site # 3: Wadi Allaqi Wadi Allaqi, the largest wadi in the south of Egypt’s Eastern Desert. It is an extensive drainage system; the length of the main Wadi Allaqi channel being about 250 km, 200 of which is in Egypt and approximately 50 in the Sudan. Its width ranges from 2 km in some parts to 10 km in some other parts. Its catchment area extends from the coastal mountains of the Red Sea , to the wadi’s outlet into the Nile Valley in Lake Nasser. Although the region in general is characterized as hyper-arid, its biogeographical characteristics are varied and transitional between the tropical biota of the south (Sudano-Saharan and Ethiopian), and the temperate biota of the north (Mediterranean). Temperatures fluctuate widely, with summer means often exceeding 40° C, while sub-zero temperatures have been recorded during winter months. Relative humidity of the air is from zero to no more than 40%. In the main part of the Wadi across the Egyptian part of the Eastern Desert, annual precipitation rarely exceeds 5 mm annually and is highly variable across seasons. This average is only fictitious because rain events occur only every 2 or 3 years, at any season and anywhere. It often comes in cloudbursts which result in torrents flowing briefly in the tributary wadis, although many years may pass without any rainfall at all. Because of this the phenology of biota (periods of reproduction) do not follow the usual annual rhythm, as elsewhere in other ecosystems having a regular annual rainfall season, but rather a pluri-annual one. Fluctuating temperatures have very little effect on plant life, as there are almost no annuals, and no perceptible effect either on animal life, which hides in burrows at extremely high or at extremely low temperatures. Species resist drought for many years before getting a chance to reproduce and renew their life-cycles. Following the construction of the Aswan High Dam and the creation of Lake Nasser in the 1960’s, rising lake water penetrated into the downstream reach of the Wadi and inundated about of its third. This brought water deep into a formerly hyper-arid ecosystem. Fluctuations in Lake level from one year to another, leads to temporary exposure of up to 40 km of this inundated area, followed by subsequent inundation each year. A new transitional ecosystem (an ecotone) between completely dry land upstream and permanently inundated land downstream has thus been established. Considering that natural vegetation occupies a very limited area, in a relatively narrow wadi channel (mountain surfaces having no plant life at all), the Wadi Allaqi is, astonishingly, floristically rich with 127 species of higher plants, that have been recorded within more than two decades of intensive research. Despite there being no endemic species, a few of these plants are very rare in the Egyptian flora About 15 species of Globally Endangered or Threatened animals and birds live there, which easily cross the border between Egypt and Sudan. These include the Sand Cat (Felis margarita), the Nubian Ibex (Capra ibex nubiana), the Nile Crocodile (Crocodilus niloticus), the Greater Spotted Eagle (Aquila clango), and the Eagle Owl (Bubo bubo). The great value of this biodiversity is that this community (biocoenosis) is an example of one of extra-ordinary adaptiveness and survival, not only to drought, but to uncertainty and randomness of availability of life-support resources, that life on earth has developed in such an extremely harsh environment. There is also a particularly rich archaeological record in the Wadi Allaqi area, that includes petroglyphic and other evidence of a Prehistoric occupation culturally distinct from that of the Nile Valley. Inscriptions of the Fifth Dynasty confirm that this region was not only used as a caravan route, but also that stone for sarcophagi was quarried here. In the Old Kingdom, Wadi Allaqi was a place of contact between Egyptians and the tribes of the Nubian Desert, playing a very important role in the economic, social, and cultural life of this part of the desert. It is most probably here that the ass and the cat were domesticated by the Ancient Egyptians. As is well known, the domestication of these two animals is the only case of its kind in Africa. In almost every tributary of Wadi Allaqi there are remains of human settlements of different periods, including for mining gold. One of the most important of these mines, the Umm Gerayat mine, had a continuous history which extended to the early decades of the 20th century. Wadi Gabgaba in the Sudan side is rich with remains of what seems to be an extensive Neolithic occupation: tombs, settlements, rock inscriptions, etc. The contemporary population of Wadi Allaqi and its tributaries is virtually unique in Egypt. The Ababda Arabs live nearer to the Nile Valley, while the local Bishari, or Bisharin (of Hamitic origin) are a branch of the large Beja Tribe (or cultural group) extending on the Red Sea coast as far as the Horn of Africa. They speak an ancient Hamitic language, the Bishari language. The material culture of both Ababda and Bisharin is distinct from that of the Nile Valley or of other Arab Bedouin groups further north in the Eastern Desrt (the Maaza in the northern Eastern Desert near Hurghada, or the Hawitat in the Suez Canal area). Many of the Wadi Allaqi tribal groups, particularly in the upper reaches of the Wadi system, remain fully nomadic, while in the Lake Nasser vicinity or in the lower Wadi reaches, household movements tend to be more localized. One very important aspect of Wadi Allaqi is that it has been for centuries a route for camel caravans from the eastern Sudan to be sold in Egyptian markets in Cairo. These caravans, called dabouka, have from 1000 to 1500 camels each, and scores of them traverse the desert each year; hundreds of camels die on the way from thirst and exhaustion, and these become food for the Egyptian vultures, Neophron, perching on Acacia trees waiting for their luck. Ababda Arabs of the Wadi help these caravans with guidance, water, and food.