Deliberations on the fourth day of the Manitoba-Israel Water Conference focused on two main issues relating to the care of wetlands and shallow lakes.  The Israeli participants presented research on the creation of and the changes that have occurred in the area since the drained agricultural peat lands were re-flooded. At the conclusion of the day’s discussions the participants toured , to observe first hand the extensive development that has taken place at the site, thanks to Friends of KKL-JNF worldwide.

The visiting Canadian scientists, for their part, showed how the disappearance of wetlands has affected water quality and carbon emissions. They demonstrated the influence of human activity on the Great Lakes of North America, discussed approaches to dealing with pollutants and presented research on the vulnerability of (greater than the entire State of Israel) to degradation.

Dr. Moshe Gophen begais review of New Developments in the Hula Valley by reference to the continual drop in annual rainfall levels in the region over the past four years. He reviewed the processes that took place between the 1950s (when the shallow and 3,500 dunam of surrounding marshland were drained and prepared for agriculture) and 1990, when a portion of the drained area was re-flooded because of the serious changes undergone by the peat lands: drying out, subsidence and spontaneous underground combustion. The peat had crumbled into a dust rich in nitrates and phosphorus which, when carried by the waters of the Jordan down to the Kinneret, seriously damaged the quality of the water and created the ideal environment for the growth of toxic algae.

Water flow in the Hula’s new wet areas was carefully planned and regulated. Nitrates and phosphorus compounds were removed with the help of reservoirs and, after dilution with water from the , were diverted to irrigate orchards on the slopes of the Naftali Hills. Hula serves as a giant filter in which water is retained for between 36 and 63 days, depending on the season and the strength of water flow in the . During this period the water in the lake undergoes a natural purification process: sediment and nitrate-bearing organic materials sink to the bottom, leaving cleaner water to flow out of the lake.

Dr. Gophen, working in conjunction with scientists from Manitoba and Mexico, has proposed the establishment of an Internet-based network for research into wetlands and shallow lakes, so that existing information can be exchanged on related topics, including seepage of fertilizers and other pollutants detrimental to water quality; the socio-economic value of wetlands and shallow lakes; and their role in determining water quality levels in freshwater lake catchment basins. “Lake Winnipeg and the Kinneret face shared challenges regarding their agricultural catchment basins, the accumulation of fertilizers and the important uses to which their waters are put,” said Dr. Gophen at the conclusion of his speech.

Dr. Iggy Litaor spoke on Hydro-chemical Characterization of an East Mediterranean Altered Wetland (). This research, conducted under his direction, deals with the water flow regime in and its influence on downstream water quality. In the course of the research, seepage of the main chemical compounds was measured, and extensive field trials were conducted to determine the constituents of the connection between the Hula flood lands and the rivers, with the contribution of each stratum of soil (deep peat, surface peat and mud) being examined. A link was found to exist between the direct and uncontrolled flow of water from to the eastern channel of the and the presence / varying depth of fissures at below-ground levels. This water flow is also influenced by water levels in the eastern channel of the Jordan, which carries most of the river’s waters southwards: the lower the water level in this channel, the stronger the flow from the lake into the river, and vice versa; when water levels in the eastern channel rise beyond those of the lake, water flows underground into the peat lands around the lake. The drier the upper stratum of peat becomes, the greater the quantity of salts that rise to the surface, because of swift water evaporation in the upper strata.

The Canadians began by presenting a method for planning hydraulic research in wetland basins. Dr. Shawn Clark of ’s Faculty of Engineering described the unique nature of ’s many flood lands and wetlands and spoke of the need to understand their influence on the quantity of fertilizers (nitrates and phosphorous compounds) to be found in the lakes bordering on these wetlands. ’s wind regime and weather often serve as a catalyst in the transfer of these substances between drying wetland and the adjacent shallow lakes, he explained.

Dr. Clark spoke of the need to determine the factors involved in facilitating the movement of water between wetland and lake and between different areas within wetlands. The physical characteristics of the wetlands and the channels that connect them to the lakes have likewise to be determined precisely, he said. Climate conditions (the formation of a layer of ice in winter as an additional constituent of the open waters environment) must also be taken into consideration, he added, and a model has to be developed that will lead to a better understanding of water regimes in wetlands and serve as a means of forecasting the outcome of measures taken to remedy the existing situation.   

According to Dr. Clark, serious field work for this prolonged research program is due to begin in the course of 2010, with the eventual aim of developing sophisticated measuring and assessment models that can be used with a high degree of confidence to determine what steps should be taken in the future to improve the condition of the wetlands described.  

Dr. Pascal Badiou, a senior researcher at Ducks Unlimited, ’s Institute for Wetland and Waterfowl Research, reviewed research into the effects of the loss of wetlands in south-west . These research projects were motivated by the lack of existing information on the role of prairie wetlands and their contribution to human society. One such piece of research investigated the wetlands’ role in the creation of carbon compounds. Information gathered from dozens of monitoring stations throughout reconstituted wetlands (areas that had been previously drained and dried) revealed that, although they emit methane gas, wetlands actually function as carbon-compound sinks.

The research institute also conducted a series of research projects that focused on the catchment basin of a river that flows into , in order to examine the effect of wetland loss on the quantity and quality of water in the river. The findings clearly show that the presence of areas of wetland in the river’s catchment basin play a vital role in reducing the quantity of organic material carried down to , especially in springtime, when the snow and ice melt. From the results of the research it can be inferred that it is worth investing in wetland rehabilitation in order to safeguard the quality of the water in . In addition, the research shows that all methods used at present to monitor water quality in the Canadian prairie areas need to be upgraded, so that the rate of seepage of organic nutrients into lakes and rivers can be precisely determined.

Dr. John Lawrence of the Canadian National Water Research Institute spoke of the effect of human activity on the Great Lakes of North America. This research is accompanied by a number of different approaches to the management of these lakes. Dr. Lawrence reviewed the main sources of pollutants of the , with industry, agriculture, forestry and mining foremost among them. The condition of the lakes, which was stable until the beginning of the 20th century, has deteriorated since, and in the 1940s fish began to die, harmful algae appeared, oxygen levels in the water dropped and toxins were found. These phenomena were especially prevalent in areas where swift urban development had taken place at the time. Today the are home to 10% of the population of the and 30% of the population of , and some of the world’s largest industrial complexes operate on their shores.

In the early 1960s ongoing scientific research began to investigate the reasons behind the deterioration of water quality in the . It gradually became clear that one of the causes of the rise in phosphorus levels – for example – was the flow of detergent-polluted water into the lakes. Quite naturally, and the recognized the necessity for joint action to reduce the damage done to the waters of the and in 1972 an extensive scientific cooperation agreement on the issue was signed between the two countries. However, despite their combined efforts to reduce pollution emissions, large strata of polluted sediment persisted in all the , resulting in the almost complete disappearance of a number of species of fish and other aquatic creatures.

Today, when fewer “traditional” pollutants dating back to the early 20th century flow into the lakes, monitoring and research focus primarily on the new generation of pollutants, such as fire retardants or medicines whose presence is a cause for concern. As many of these substances cannot be removed by supervision at their place of origin, measures have to be taken to prevent their release into the environment. This is where new research is needed into improved methods of sewage purification that could be used to degrade these substances or limit their quantity in the treated effluent that flows into the lakes.  In the quality of the water in , the sixth largest lake in , is cause for increasing concern. The appearance of harmful invasive species and of a variety of toxins poses the main threat to water quality in the lake. Within two years, however, research underway today is expected to provide sufficient information to allow scientists to determine the desirable level of nutrients in the lake’s waters.

The final lecture was delivered by Dr. Henry Venema of the International Institute for Sustainable Development, who spoke of the influence of climate on . Most of the climate’s adverse effects are the result of frequent periods of severe drought in the area of the lake’s catchment basin. The dry weather increases the amount of dust in winds and rainwater and, as this dust contains nitrates and phosphorus compounds, these are eventually conveyed to the lake. The research identified the agricultural plains of southern as the main source of pollution, and has made recommendations as to how the agricultural sector caelp to restrict water pollution during long periods of drought. The findings of this research, too, indicate the necessity of using wetlands as a natural barrier against pollution, as much of the damaging organic silt sinks naturally into marshland and remains trapped within it.




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