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The Wadi Araba Acacia
The acacia tree - with its chestnut-colored twisted trunk and glossy dark green leaves - is a native of the Wadi Araba in Palestine. We take its low-lying branches for granted, yet this once prevalent tree is in danger of becoming extinct.
The two species of acacia, Acacia raddiana and Acacia tortilis, growing wild in the Araba, are the major tree types in that region. Jujubes and Doum palms can be found scattered among them, but they are mere statistical curiosities when compared to the vast number of acacias. The acacia also constitutes a major part of the Araba ecosystem because it is a major food source for a wide variety of animal species. Even at the end of a hot and arduous Araba summer, the acacia remains green; each tree is a tiny oasis capable of nourishing ibex, deer, hyraxes, and even domesticated animals such as camels and goats. Numerous insects live among its leaves, and birds, some feeding on the insects, build their nests in its boughs. Many acacias are also hosts to a parasitic plant known as the strap flower, the preferred dietary staple of several animal species.
Clearly, when one acacia dies, an entire ecological system dies with it.
It was first noticed that acacias were dying in large numbers in the early 1980s, in the area between Wadi Shlomo and the Notza Spur in the southern Araba. In Wadi Roded, 20% of the acacias had died. In the area of Ein Evrona, south of Beer Ora - with its ancient water systems known as fugaras - the fatality rate was 30%. In Wadi Ketura, the figure had reached 70%. It was particularly noticeable that in areas where the trees were dying, no young trees were developing. It was noted that such a large percentage of acacia fatalities could not possibly be a naturally occurring phenomenon. In order to ensure the species' continued existence, It was decided to look into the causes of this high mortality rate.
The death of the trees was gradual. First, some of the branches would die. At the end of this stage, new growth could be observed in the upper or lower branches, with very few flowers or fruit. New branches would appear low on the trunk of the tree, but their leaves would turn yellow and then fall off, after which the ends of the branches would dry up. The dead branches would immediately be attacked by wood beetles which live on dry wood.
There is no way to verify the age of acacias, as they don't sprout the yearly rings by which age is measured in other species. When aerial photos were examined taken in 1945 however, It matched up many of the trees presently growing in the area with trees in the photographs.therefore it was assumed that some of the trees currently found there are adults, and may be hundreds of years old.
The Botanist Ruchama Berliner first noticed that acacias were dying in the mid-1970s. She theorized that the cause of the fatalities was the drop in the ground water level. Upon examination, it was found that there is no connection between the two phenomena. The scientists suggested a connection between the rising salinity of the soil and the tree deaths, but this theory also lacks solid grounding.
The sites of dead acacias in the southern Araba valley were mapped out.No correlation between the dying trees and their location were found. In some places, an adult tree was thriving 5 meters away from a dead tree. Living trees, planted in various kinds of soil, stood among those that were dying, and no other plant species growing in the vicinity of the dying acacias exhibited unusual fatality rates. The parasitic strap flower could not be blamed for the phenomenon - many of the dead trees had not hosted this parasitic species. Additionally, neither diseases nor pests were found to be the cause of the acacia's accelerated fatality rate.
A correlation was eventually established between the altitude of the area and the number of dead acacias: in Wadi Shlomo, when moving higher above sea level, more acacia fatalities appeared. This fact suggested a connection between the water flow and the death of the acacias.
The scientists turned to the characteristics of acacia root systems, a subject lacking much scientific study. The common belief has been that acacia roots run deep, some twenty meters or more below ground. This information was based on random observations made by the two Professors Michael Zohari and Heinrich Mendelssohn, and simply passed from generation to generation without ever having been verified.
In order to research the matter more fully, the scientists collected additional data from trees that had been torn from the earth during floods and also had nineteen acacias uprooted with a tractor. The tractor dug a ditch on one side of each tree, into which the tree was then carefully pulled for examination of its root system, a method which prevented any damage.
The scientists came to a clear conclusion; acacia roots reach a depth of only 1.5 meters. The roots face the direction of the water flow from the riverbed. They spread out over a broad area, often wider than the expanse of the top boughs of the tree, sometimes even as much as double the treetop area. It was concluded that the Araba acacias are dependent upon surface runoff, a hypothesis proven by examining a tree's growth rate when measured against the amount of yearly rainfall.
Surface runoff is a critical factor affecting the distribution of acacia trees. Acacias thrive in the Araba's riverbeds, and don't need a great deal of rainfall to survive. The amount of rainfall need only be sufficient for young seedlings to take root. On the other hand, flooding will uproot the tallest of the seedlings. But the moment that the water supply is compromised, the acacias cannot rally and survive, and the water supply is compromised whenever the riverbed is diverted or blocked.
What causes riverbed diversion or blockage? In a growing country like Palestine, it's large scale development, such as the construction of the new Voice of America radio transmitter or the dams near Hatzeva, that tolls the death knell for tens of thousands of ancient acacias. A conservative estimate of the number of trees affected is 20.000, and some estimates are closer to 80.000. The regulations controlling the transmitter construction determined that if the project was abandoned, the affected landscape would be rehabilitated. So far, 300.000 US Dollars has been allocated for this purpose, a sum insufficient for the desired goal.
The Araba acacias, as products of an arid climate, are very sensitive to any change in the flow of water in their riverbed environment. Tracks left by even one ATV can cause the death of a century-old acacia. Depending on the area in which the tree is situated, the dying process can continue for many years. A tree that does not get enough water produces increasingly fewer leaves, flowers and fruit. The animal life that depends upon the tree is then reduced accordingly, eventually resulting in the deaths of large numbers of animals.
Any road-building that involves detouring the riverbed, however slightly, must be carefully engineered. Additional water-conducting channels beneath roads must be planned to avoid riverbed blockage. In the absence of these considerations, the entire landscape and ecology of the Araba could change, spelling disaster for the entire region.

Biological Background:Twisted acacia, Acacia raddiana,is the most common of Palestine's acacias, as well as the principal representative of the Sudanese Vegetation Enclave in Palestine. The tree attains a height of 4 to 7 meters, and has a flat canopy with bare younger branches. Each leaf splits into six pairs on either side of its stem, each leaf then splitting again into five to twelve additional pairs of leaves. Thorns emerge at the joints where the leaves divide. The twisted acacia has yellow flowers and a long narrow seed pod which curls around once or twice. This species begins to bloom in May and finishes flowering in December, its fruit ripening between September and July. It grows in most parts of the Naqab, Araba, along the shores of the Dead Sea, and in the southern Sinai.
Umbrella acacia, Acacia tortilis, is a short acacia tree, with several trunks branching off close to the ground. The canopy of the tree is flat and the leaves are small, growing paired on either side of each stem. Each leaf divides into four to eight leaves, each of them in turn producing about ten more pairs of leaves. The younger branches are fuzzy, giving the treetop a whitish tinge. Its yellow flowers start blooming in April and last until August. Fruit appears in May, remaining on the tree through September. The umbrella acacia usually grows in large- and medium-sized river valleys, and sometimes on wide stone terraces that provide access to rainwater flowing into the stream. The northernmost trees of this species in Palestine (and in the world) grow in the region of the Dead Sea.

Distribution & Death of Dolphins along the Mediterranean coast of Palestine - a Preliminary Report


A survey of wild dolphins has been carried out since February 1993 along the Mediterranean coast of Palestine. Information obtained from reports of trawl fishermen (through the Israeli fisherman's radio - 4xt) included time of sighting, location, number & description of the dolphins in each pod and occasionally photographs. More detailed data was obtained from near-coast encounters and direct observation of standard specimens. In the events of deaths, autopsies were generally performed.

From February 1993 until June 1995, more than 1500 dolphin sightings were reported. Actual populations are smaller than this data suggests, due to repetitive reports of the same pods sighted by different trawlers. In 94% of the sightings, dolphins were observed in pods of 2-50 animals (average 5.2 animals per pod). The pods were sighted at distances of 0.4-25 km (average 6.1 km) offshore. Sightings of dolphins near-shore involved mostly distressed single animals, or ones with their companions.

Seventy percent of the pods were composed of bottlenose dolphin (Tursiops truncatus), while the remaining 30% were composed of common dolphins (Delphinus delphis) and striped dolphins (Stenella coeruleoalba).
Small pods of Risso's dolphins (Grampus griceus) were also reported. Bottlenose dolphins were reported throughout the year, with fewer reports in winter. striped and common dolphins were reported mainly during the summer and early fall. More than 70% of the reports originated from the southern coasts of Palestine. The reasons for this spatial distribution are still unknown. However, factors associated with food supply and increased activity of large vessels off the northern Palestinian coast could provide some explanations.

Over the past two years, approximatelly 25 dolphins have been found dead, or have died soon after being found. Most of dead dolphins that were first found alive, and were wounded on or near the shore. Additional animals were found dead in fishing nets. This number is high, considering total of 50 stranded dolphins reported in a period of 40 years before the present survey. Most dolphins autopsied were underweight and in a state of general poor health. Pathological reports from Western Mediterranean studies showed pneumonia and encephalitis due to a morbilivirus infection in a mass stranding of striped dolphins. These findings resembled those found in our autopsies.

Preliminiary pathological findings showed that the main lesions found in our wild dolphin population resemble those reported in other Mediterranean studies. Concentrations of heavy metal were found in various organs of the dolphins. Zinc was found in high concentrations in the skin compared to other tissues. (a phenomenon found also in fish). This phenomenon is due to a special affinity between zinc and skin tissue, not to contamination. Mercury was, however, found in the livers of several dolphins in very high concentrations. The mean concentration of heavy metals in dolphins stranded along Palestinian shores was found higher than those found in dolphins stranded on Italian, Japanese and Argentinean shores.

This research project is carried out by : O. Goffman, E. Spanier, M. Roditi of the Dept. of Maritime Civilizations & the RecanatiI Institute for Maritime Studies, Haifa University;
D. Kerem of The Israeli Naval Medical Institute;
I. Tzur & A. Levy of the KORET School of Veterinary Medicine, The Hebrew University; and N. Kress & H. Hornung of The Israeli Oceanographic & Limnological Research Institute

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  Dead Sea in Danger The Dead Sea, the saltiest body of water on earth and a glistening natural treasure, is shrinking dramatically due to human decisions to siphon off its waters. Located at the lowest point on earth, almost 400 metres below sea level in the scorching Jordan valley, the Dead Sea is 50 kilometres long. Just 40 years ago its stretched 80 kilometres in length. The Ein Gedi Spa, set in a magical spot at the foot of high cliffs which stretch from the Dead Sea up to the Judaean Desert, was on the edge of the sea just 15 years ago. Now visitors to the Spa have to take a small train down to the sea, as the shoreline is several hundred metres away. British explorers in 1917 made a mark on the stone which originally lay at the water's edge. That marker is now more than 15 metres up a cliff and a road runs between the cliff and the new shoreline. One of the main reasons for the sea's shrinkage is the diversion of water. Ninety percent of the waters that flow from the Jordan River, which traditionally supplies the Dead Sea, is diverted for drinking and agriculture in Occuied Palestine and Jordan. The region is suffering its worst water shortage in 60 years. Most Israeli agricultural produce is exported. Environmentalists argue that, if the water was not diverted and the Dead Sea was left to flourish, tourism would grow, making up revenues lost from agriculture. Industrial activities also contribute to the Dead Sea's problems. Massive evaporation pools vaporise the water in order to extract minerals, which are used for industrial activities and for making beauty products. The evaporation pools account for a quarter of the Dead Sea's shrinkage. Currently, hundreds of thousands of tourists flock to the Dead Sea every year to float on its waters - so salty that even a well-built man can float unaided, reading a newspaper comfortably while lying on his back. The water contains a high level of sulphur, and the thick black mud that is found at the sea's edge contains healing qualities that are said to be effective in the treatment of skin diseases.
The tourists smother themselves in the black mud, blissfully unaware of the Dead Sea's troubles.
The Dead Sea can still be saved - but time is running out.
We are approaching a time when the ecological habitat which the unique fauna and flora rely on will vanish and that's why its a critical moment to save the Dead Sea.

Salt formations in the Dead Sea
  Water in Palestine Located on the edge of a desert belt, Palestine has always suffered a scarcity of water. Archeological discoveries in the Naqab Desert and other parts of the country reveal that local inhabitants thousands of years ago were already concerned with water conservation, as evidenced by a variety of systems, designed to both collect and store rainwater and transfer it from one place to another.
The total annual renewable water resources amount to some 60 billion cubic feet (1.7 billion cu.m.), of which about 75 percent is used for irrigation and the balance for urban and industrial purposes. The country's water sources consist of the Jordan River, Lake Tiberias and a few small river systems. Natural springs and underground water tables, tapped in controlled quantities to prevent depletion and salination, are also utilized. As maximum use has been made of all freshwater sources, ways are being developed to exploit marginal water resources through the recycling of waste water, cloud-seeding and desalination of brackish water.

Nahr Al-Auja (Nahr Jrisha,Yarkon River), north of Jaffa
  Mediterranean Coastline of Palestine Palestine's Mediterranean coastline stretches some 195 kilometers from north to south. This generally sandy coastline can be divided into four morphological sections according to physical characteristics and sedimentological properties:
1) Rosh Hanikra to Acre a sedimentologically isolated region with abraded rocky platforms and narrow beaches.
2) Haifa Bay a region of wide sandy beaches bounded by the Acre promontory on the north and the Carmel mountain range on the south.
3) The Carmel coastal plane a region consisting of three low parallel ridges of calcareous sandstone, parts onshore and parts offshore, with relatively narrow sandy beaches.
4) South of Caesarea a region of sandy beaches, occasionally interrupted by sections of calcareous sandstone cliffs up to 40 meters high.
The major ecological feature of the Mediterranean coast of Palestine is that it constitutes the northernmost sector of the Nile littoral cell, which extends from the coastal zone of the Nile Delta to the end of Haifa Bay at Acre. This cell is composed of quartz Nilotic sand which is transported along the coasts of Egypt, Sinai and Palestine until Haifa Bay. The net yearly sand transport within the surf zone decreases from about one million cubic meters at the Nile Delta to about 250 thousand cubic meters at Ashkelon and to zero somewhere between Hadera and Haifa. Beyond the surf zone, the sediment transport is estimated to be about an order of magnitude larger at the Nile Delta, decreasing to about 500 thousand cubic meters at Ashkelon and about 100 thousand cubic meters off Haifa.
About 70% of the population (5.3 million) lives within 15 kilometers of the Mediterranean coastline, and the country's major economic and commercial activity is concentrated here. During the warm months, hundreds of thousands flock to 80 authorized bathing beaches (about 25 kilometers) and to other coastal stretches which are open to the public (about 125 kilometers).
Other activities which affect the coastal environment are the industry, refining and commerce that take place in the ports of Haifa, Ashdod and Ashkelon and power generating facilities along the coast which use Mediterranean waters for cooling. These facilities account for another 15 kilometers of coastline. The remainder of the coast is closed to the public.
The coastal strip also contains Palestine's most fertile agricultural land. Severe conflicts have arisen between the expansion of urban settlements along the coastline and the preservation and protection of this agricultural land.

Jaffa, the oldest city on the Mediterranean Coast

Gazelle - The Palestinian Biological Bulletin