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The Deterioration of Wetland Ecosystems in Wadi Gaza, Palestine By: Ayman Wadi’ Dardona, M.Sc. Limnology and Wetlands Management E-mail: dardonageo@yahoo.com
Introduction Wadi Gaza is situated in the middle of Gaza Strip in the south of Palestine. This Wadi is one of the furthermost important wadis in Palestine. It extends for more than 90 km beginning from the western foothills of Hebron Mountains and Beersheba lands and drain to the west into the Mediterranean. It flows occasionally during and after periods of heavy rainfalls. The final portion of the Wadi which lies in the Gaza Strip extends 9 km from the truce line in east Gaza to the coast where it discharges into the Mediterranean Sea. See Figure (1).
Figure (1): Location of Wadi Gaza wetland
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The width of the Wadi fluctuates from one place to another; and it is at its widest near its mouth where it forms a wetland or an estuary lake which is the most important habitat for migratory and resident water birds in the Gaza Strip. The wetland is bordered by tall emergent plants like Phragmites australis and Arundo donax. Tamarix nilotica covers considerable areas as part of the maritime influence of the estuary lake (MedWetCoast, 2003). Photo (1) shows the common reed in the wetland.
Photo (1): The common reed in Wadi Gaza wetland. By: Ayman Dardona. 16.10.2014
This article deals with the ecological status of this wetland. Generally, wetlands are lands where saturation with water is the dominant factor determining the nature of soil development and the types of plant and animal communities living in the soil and on its surface (Cowardin, 1979). Wetlands have great importance and values that keep the ecosystem working in efficient way. Wetland functions are defined as a process or series of processes that take place within a wetland. These include the storage of water, transformation of nutrients, growth of living matter, and diversity of wetland plants, and they have value for the wetland itself, for surrounding ecosystems, and for people. Functions can be grouped generally as habitat, hydrologic, or water quality, although these distinctions are somewhat arbitrary and simplistic. For example, the value of a wetland for recreation (hunting, fishing, bird watching) is a product of all the processes that work together to create and maintain the wetland (Novitski, Smith & Fretwell, 1996). Gazelle : The Palestinian Biological Bulletin – Number 131 – November 2015
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The wetland in Wadi Gaza signifies the only riparian and swamps ecosystems in the Gaza Strip; the only known estuary appears there at the end of the Wadi near the sea. The main source of water in the Wadi Gaza wetland is rainfall. Wadi Gaza has a typical semi-arid Mediterranean climate, hot in summer and cold in winter. Peak months for rainfall are December and January. Since the early 1970s and after the implementation of retaining dams and diversion schemes by Israel on the upper course of the Wadi, the volume of water reaching Wadi Gaza began to diminish considerably, and large flows are restricted to occasional flash floods sweeping down the Wadi bed in wet years (Awadallah, 2000), and the other source of the wetland water is the ground water through the fens and seeps. Fens and seeps receive water from groundwater sources. This means that the water table and soil surface reach the same height. These wetlands can be fed by an underground water source and often contain high concentrations of nutrients that stimulate plant growth (http://www.motherearthnews.com/nature-and-environment/wetlandszbcz1308.aspx ) .The nature of soil in the area allows water to be saturated.
Photo (2): A side of the Wadi Gaza wetland. By: Ayman Dardona. 12.10.2015
The Ecological Importance and Values of Wadi Gaza Wetland The main estuary lake of the wetland contains permanent fresh water which serve as good habitat for several fauna and flora such as several water birds, frogs, and freshwater turtles (MedWetCoast, 2003) and several aquatic flora specially Tamarix nilotica which is the most abundant one; Phragmites australis, Typha, and others. In addition to this fresh water lake, artificial wetlands have been created where Gazelle : The Palestinian Biological Bulletin – Number 131 – November 2015
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untreated sewage is allowed to drain into the current of the Wadi. These backwaters of the estuary and the sewage lagoons contain shallow waters which support many wading birds (herons, egrets, ibises, rails, crakes, stilts, plovers, stints, snipes, ruffs, red and greenshanks and others). Photo (2) shows a side of the wetland. The wetlands serves as stop over for several migratory birds; and due to the geographical position of Palestine and the location of the Gaza Strip at the corner of the land bridge connecting the continents of Africa and Eurasia. The passage of many migratory birds between the Orient and the Nile valley also takes place through the Gaza Strip. Thousands of ducks, herons, storks, cranes, flamingos, waders, raptors, quails, passerines and other birds have been reported to pass through the Gaza Strip. On the other hand, the wetland has several ecological, economic, and folkloric importance. Several floras exist in the area. The flora and fauna in the wetland play integrated role in serving habitats for each other. Common Reed Phragmites australis is a large perennial reed and is very common in fresh and brackish water marshes. The species is invasive and produces dense mono-specific stands. The Moorhen Gallinula chloropus and Coot Fulica atra were common breeding birds in the reed marshes and they use it as nest material timber (Abd Rabou et al, 2008). Tamarix nilotica is a tall salt and drought tolerant shrub; it forms dense and extensive mono-specific stands, especially in the central section of the downstream part of Wadi Gaza. An immense variety of wildlife and domestic species exploits the dense areas for resting, nesting, foraging and other purposes. The plants are overexploited for its timber (Abd Rabou et al, 2008). The third most dominant plant in the wetland is Arundo donax. See Photo (3) below. The Giant reed is similar to the Common Reed in its ability to establish a large monoculture area. It usually inhabits moist habitats not far away from the wetland ecosystem of Wadi Gaza.
Photo (3): Mixture of Tamarix nilotica and Arundo donax around the wetland edge. By: Ayman Dardona. 12.10.2015.
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The plant was observed to harbor an immense variety of wildlife species e.g., the Egyptian Mongoose Herpestes ichneumon and Moorhen Gallinula chloropus. See photo (4) below.
Photo (4): The moorhen in Wadi Gaza wetland. By: Ayman Dardona. 12.10.2015.
In addition to this ecological importance, the wetland in the Gaza strip has the potential to be a site for ecotourism, birding, and scientific research. There were several studies and experiments around the wetland; the most important was for studying the aquatic birds; around 49 species of them were recorded (Abd Rabou et al, 2007), and 219 flora species were recorded in the area (Abou Auda et al, 2009). These studies show that the wetland is important in terms of biodiversity and habitats richness. In other fields of scientific research, it is found that the Phragmites australis in pilot experiments indicate good results in nutrients removal and could be a way for natural wastewater treatment, and may give an idea of the constructed wetlands for wastewater treatment in the area of Wadi Gaza. The wetland estuary is a unique ecosystem; fishes are recorded there and in the wetlands, they move from and to the sea (MedWetCoast, 2003). This means the potential of aquaculture in the wetland area.
Discussion of Threats and Actions Studies show that there is an urgent need to protect the Wadi Gaza and its surrounding vegetation communities as these habitats contain the highest value for the flora and fauna. The threats to these habitats are quite severe; Wadi Gaza faces Gazelle : The Palestinian Biological Bulletin – Number 131 – November 2015
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many environmental problems that affect the public health and is used as a point to collect sewage from the middle area refugee camps and as a solid waste-dumping site. See photo (5) below (http://whc.unesco.org/en/tentativelists/5722/).
Photo (5): Dumping the wetland in Wadi Gaza. By: Ayman Dardona. 02.06.2015
Through my frequent visiting to the Wadi and specially the wetland, it was found that the main problem in the site is the direct discharge of the raw sewage to the sea through the wetlands, this led to the mixing of freshwater with sewage to form brackish waters and polluted waters with high concentration of nutrients and sludge; this reduce the ecological function of the wetlands, and decrease the possibility of recreation in the wetland area. Another threat factor to the wetland is making it as a dumping site and also burning the trees and dumping the swamps by the local people in order to solve the mosquito’s problem, especially in the summer. The high increase of nutrients due to the raw sewage made an imbalance in the ecosystem; this led to the eutrophication due to the huge growth of algae. The reduction of groundwater and the decline of the groundwater level far from the surface, and the little precipitation also reduce the level of soil saturation and water Gazelle : The Palestinian Biological Bulletin – Number 131 – November 2015
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level in the wetland. Nowadays, few natural parts are still found in the wetlands, but due to the high stress that it faces, if there are no urgent actions, the wetland which is the only coastal one in the Gaza strip may be wiped out. Anyway, the instability of the wetland ecosystems in the Gaza strip did not yet mean the full deterioration of the wetland, but at least it lost a lot of its function. No real studies yet consider the carbon accumulations in the wetland, the vegetation degradation, and habitats degradation. But at least through our frequent tours to the Wadi, it is noticed that several flora, specially aquatic ones are almost extinct; the most common one of them is the Shrubby Swamp-fire Arthrocnemum fruticosum, it is a perennial plant which grows in the shallow saline depressions, where the soil seemed moist and white due to salt accumulation; this may be an indication of the partial loss of these depressions and swamps as well in the wetland area. Also if we compare the status of the Wetland before and after 15 years, it is clear that several aquatic fauna disappeared due to the disappearance of their habitats. It was in 2004, when I saw the fresh water turtle for the last time; all indications show that it is vanished, but we cannot endorse that; also a lot of aquatic birds were not observed since a long period. Though this deterioration and damage of the ecosystem, some little biota is still around such as the common toad, little egret, ringed plover, common snipe, cattle egret, blackwinged stilt, Redshank, Sanderling, Gulls, Moorhen, coot, and the Spur-winged plover. See photos (6), (7) & (8) below.
Photo (6): The common toad in the Wadi Gaza wetland. By: Ayman Dardona.16.10.2014
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Photos (7 & 8): Black-winged stilt in the Wadi Gaza wetland. By: Ayman Dardona. 15.11.2014.
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Urgent actions should be taken to protect and conserve the wetland ecosystem in the Wadi Gaza and recover its ecological functions, to still serve as good stopovers for aquatic birds and other fauna. The first step should start from the local people, they should be part of any plan; they are the most effective stakeholder in any action. A detailed framework and public awareness strategy should be achieved taking the local people as main partner. Actually this needs the rebuilding of the institutional bodies responsible for the Environment sector in the Gaza strip. The local government should take a part; researchers and ecologists should make several researches. Lastly, to save what still exists of the wetland is a national and international responsibility. The disappearance of the wetland may have global effects in the bird conservation and climate change as well. The migratory birds may lose their stopovers and paths in their migration and that means it can take another system in the migration routes. In conclusion, urgent actions and plans should be taken in order to conserve the biota in the Wadi Gaza wetland and recover the wetland to function properly, for the sake of conserving biota, environment and public health.
References and Internet Websites Abd Rabou, A. F. N.; Yassin, M. M.; M. R. Al-Agha, M. I. Madi, M. M. Al-Wali; Ali, A. K. S. & Hamad, D. M. (2008). Notes on some common flora and its use in Wadi Gaza. The Islamic University Journal (16). 31-63 . Abd Rabou, Abdel Fattah N.; Maged M. Yassin, Mohammed R. Al-Agha, Dawi M. Hamad and Abdel Karim S. Ali (2007). The Avifauna of Wadi Gaza Nature Reserve Gaza Strip, Palestine. The Islamic University Journal (Series of Natural Studies and Engineering) (ISSN 1726-6807), Vol. 15, No. 1, pp. 39-85. Abou Auda, M. M. Deep, N. Y. & El-Sahhar, K. F. (2009). The flora and plant life forms of Wadi Gaza area, Middle Governorate, Palestine. Proceeding of the 4th Conference on Recent Technologies in Agriculture. November 3-5. Cairo. Giza. Egypt. 201-213. Awadallah, A. (2000). Wadi Gaza landscape protection area. M.Sc. Thesis, Agricultural University of Norway (NLH), Oslo, Norway. 85 pp. Cowardin, L. M. (1979). Classification of wetlands & deepwater habitats of the US. DIANE Publishing. Dardona, Ayman Wadi’ (2015). The Deterioration of Wetland Ecosystems in Wadi Gaza, Palestine. Gazelle: The Palestinian Biological Bulletin. ISSN 0178-6288. Number 131, November 2015, pp. 30-39. Dubai and Sharjah, United Arab Emirates. http://gaza-ecosystem.webs.com/ Gazelle : The Palestinian Biological Bulletin – Number 131 – November 2015
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Dardona, Ayman Wadi’ Youssef (M.Sc. Limnology) and Prof. Dr. Sc. Norman Ali Bassam Khalaf-von Jaffa (Dr.Sc. Zoology) (2015). Studying Aquatic Birds in the area between the Gaza Fishermen Port and Wadi Gaza Estuary, Gaza Strip, Palestine. Gazelle: The Palestinian Biological Bulletin. ISSN 0178 – 6288. Number 124, April 2015. pp. 22-39. Dubai and Sharjah, United Arab Emirates. http://birds-ofpalestine.webs.com/gaza-aquatic-birds MedWetCoast (2003). Management plan: Wadi Gaza. Project for the Conservation of Wetland and Coastal Ecosystems in the Mediterranean Region – MedWetCoast, 171 pp. Mother Earth News Blogs. Nature and Environment. http://www.motherearthnews.com/nature-and-environment/wetlandszbcz1308.aspx Novitski, R. P., Smith, R. D., & Fretwell, J. D. (1996). Wetland functions, values, and assessment. National Summary on Wetland Resources. USGS Water Supply Paper, 2425, 79-86. Wadi Gaza Coastal Wetlands, UNESCO World Heritage Centre. http://whc.unesco.org/en/tentativelists/5722/
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