Let’s Give Life Back to Our Rivers - UNESCO · 2014-10-08 · rivers, indeed our ancestors knew very well that without rivers life is simply not possible So gr. eat was their respect,

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When we think of the great civilizations of the past, what strikes us is that they always developed alongside a major river. Keeping rivers and the aquatic ecosystems intact was a way of guaranteeing survival for all, and the life and development of every human society has always been closely linked to the availability of fresh water. We still rely on rivers today, even if the way we view them has radically changed. In fact we are rarely even aware of their existence let alone their value. It is perhaps because of this poor perception that rivers today are in such a state of neglect and degradation, indeed sometimes the waters are heavily polluted or worse, they have no water at all! Problems regarding the quantity and quality of the water of rivers urgently need to be addressed. What can you do to help?

River = water = life. The testimony of ancient civilizations.A river is a very long passageway along which many animals and plants move and live out their lives, creating complex ecosystems. All life forms depend on these ecosystems, including humans. This is why ancient civilizations developed along rivers, indeed our ancestors knew very well that without rivers life is simply not possible. So great was their respect, they would often held rivers in deep veneration. Ancient populations were very aware that rivers, swamps, and marshy lands in which courses of water originate are the main ecological basis for the survival of all communities. In ancient Greece, as the Latin writer Virgil writes in the Aeneid (Aeneid, III, 700-1), the oracle of Apollo forbade the draining of the swamp of the ancient city of Camarina, foretelling terrible disaster for the inhabitants if they carried it out. Do you know of any similar examples about other ancient water civilizations? Tell us!: [email protected]

Exploitation of rivers on a planetary scale.Throughout the world, and in particular during the second half of the twentieth century, a widespread physical, chemical and biological deterioration took place in all river and marine habitats. Rapid population growth and the intense economic development of the XX century, with all the ensuing pressure on water resources, has more been characterized by the management of rivers for economic and productive ends rather than with regard to naturalistic or ecological factors. Throughout this process of “development at all costs”, whether a river ecosystem is in good functioning order or not has been systematically overlooked. The most profound of changes to rivers have only served to further single functions, as for example hydro-electrics, irrigation, industrial waste or navigation. In reality, rivers should not be considered as mono-functional systems, but rather as multifunctional ones.

Illustrations 1: © National Geographic – Rivers’ pollution.

Let’s Give Life Backto Our Rivers

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Illustrations 2: © Centro Civiltà dell’Acqua - Chemical and physical deteriorations are threatening rivers worldwide.

Rivers as multifunctional systemsToday it is no longer feasible to view rivers as having only a productive and economic function that entails the exploitation of their water. They must also be seen as important nuclei where culture, activities related to recreation like fishing, sport, excursions, thriving ecosystems, etc, will take on an increasingly important role. In other words rivers should be seen as multifunctional systems, rich in their diversity and ability to contribute not only to the wealth of a territory in economical terms but also in terms of raising the quality of the environment and the lives of those who live there. The re-evaluation of a river is one possible measure against the negative consequences of human activity, which has tended to alter and modify the riches of nature and rivers for purely productive purposes.

Human pressure: rivers and swamps at riskThe continual pressure brought to bear on courses of water only for productive ends has seriously endangered numerous fluvial ecosystems and their ability to function all over the world. For example, some of the longest and previously fullest rivers in the world, like the Colorado in the United States, the Amu Darya in central Asia, and the Yellow River in China, are today unable to flow out into the sea because humans have overused their waters. Even the Indo, a river which is vital to Pakistan, is sometimes reduced to a mere rivulet when it reaches the Arabian Sea. Rivers today which are still uncontaminated are only to be found in remote boreal zones or Arctic regions. According to experts, less than 20% of the rivers and flood plains of Europe are still today in a semi-natural state and functioning well ecologically. The disappearance of swamps has reached a loss of up to 60% in Denmark, and 90% in Bulgaria.

Illustrations 3: © UNESCOWetland at the Kakadu National Park, Australia

Illustrations 4: © Centro Civiltà dell’AcquaWetland near Busatello, Verona, Italy

Types of impact on riversThe physical state of rivers and waterways has been heavily conditioned in the last few decades by the construction of dams, artificial banks and canals. At the same time, changes in river flow, the action of drainage and destruction of humid zones, have totally undermined the natural capacities of rivers and their habitat, often turning them into mere places for temporary water storage. And this is not to mention the impact of the expansion of farming and urban areas, deforestation and climate change. All the foregoing factors have lead to increased risk of flooding in lower-lying areas.The chemical deterioration of the fluvial environment is not only due to industrial waste such as that derived from heavy metals, but is also strongly conditioned by pollution from industrialized agriculture (the large monocultures) due to the emission of substances from pesticides and fertilizers such as nitrogen and phosphorous.

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Illustration 5: © Centro Civiltà dell’Acqua

Biological stress and the quality of aquatic habitatsAll this undue stress on rivers has considerably undermined their capacity for self cleansing and their natural ability to retain pollutants that we saw in the section “What is a River?”. This causes serious problems for the regeneration of oxygen in aquatic environments. The combined impact of physical and chemical alteration, the growing density of human population and excessive pressure on natural resources have created an extremely high level of biological stress which consequently has negative influences on the quality of the environment for a host of aquatic flora and fauna (loss of biodiversity). Today it is estimated that the rate of extinction of aquatic fauna is 5 times greater than land fauna. River ecosystems are therefore among the environments most at risk of extinction in the world today.

The loss of biodiversityThe concept of biodiversity does not only include the various species of organisms and their many sub varieties living in a certain area, but also how these organisms adapt, and the systems they are part of. Biodiversity also comprises the human action which has been responsible over time for selecting different varieties of cultivated plants and domesticated animals, and their consequent adaptation to different environments. This particular level of biodiversity also has features of a cultural and religious nature. Today, human activity has modified between 40-50% of the world’s ice-free surface, transforming the original environments into farming and urban areas. The disappearance of natural habitats, and of tropical forests in particular, is the principal cause of extinction of many animal species and vegetation, and the subsequent loss of biodiversity like deforestation, pollution of the air, land and water. All the foregoing are side effects of development in general, and human activity is increasingly responsible for this.

A more sustainable development to counter the

unstoppable decline of the environment?From the Earth Summit in Rio de Janeiro, Brazil, 1992, to the Conference on Climate Change in Copenhagen, Denmark in 2009, the scientific community and governments all over the world are reflecting with growing concern on the unstoppable environmental decline of the planet. It is widely recognized that environmental problems are caused by humans, that they must be tackled globally, and that the solutions should involve the commitment of all nations, even if, in practice, programmes and concrete action have not always followed on from a great number of declarations.

Rivers help us. The Goods and Services of the aquatic ecosystemsThe entire human race, past present and future, heavily relies upon the good working order of the cycles of nature as well as on the “goods” and “services” supplied by ecosystems and rivers, from which we obtain so many of our daily requirements. But exactly what are these “goods” and “services”? By “goods” we mean, for example, drinking water or water for irrigation, but also food, medicine and raw material for building. By “services” we rather mean the benefits that society reaps in terms of life support, like fertile land for agriculture, fishing, renewal of drinking water, biodiversity etc. Collectively, all living creatures in a given environment constitute a patrimony of inestimable value which nature provides us with absolutely free of charge! Let’s not ever forget that!

Illustration 6: © United States Department of AgricultureThe passageway or ecotone of a river.

The degradation of ecosystems on a planetary scaleMore than 2/3 of “services” provided by ecosystems in the world are today partially or wholly endangered. This can be deduced from a number of factors: the collapse of fishing, loss of soil fertility (desertification), lowering of the water capacity of rivers, etc. The goods and services of ecosystems are further under threat from the relentless exploitation of natural resources and the loss of animal

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and plant species on a planetary scale. Two factors in particular that exasperate an already explosive situation are: technologies that need to consume natural resources in order to function, and the combined elements of population growth and increase in consumption.

Illustration 7: © WordPress - The black oil spill in the Atlantic devastates the coasts of Florida (2010).

Why is it important to re-evaluate our rivers?What do rivers mean to us? Why should we take such good care of them and want to see them regain a state of semi-naturalness wherever possible? Because rivers and surrounding areas represent a great opportunity for the communities who live nearby to put a series of ecological activities into practice which will allow for a different form of development of their territory, and raise the quality of life there. Who in the world would like to live by a smelly, black river with cement banks, full of rubbish rather than fish? No one! That’s the reason why our rivers must be re-evaluated!

Illustration 8: © Graham Matthews & AssociatesEvolution in the process of re-naturalization of a river.

Re-evaluation of rivers = quality of lifeOne necessary action against the problematic situation we have so far been describing is, as we have said, to re-evaluate our rivers starting from today. This can really be of concrete help and it is naturally in everyone’s interests. We can do so many things along a river that has been brought back to life, like run, cycle, go on excursions, go canoeing and boating, fish, swim, or simply admire the flowing water. And what is more, by reinstating the

river’s natural capacity to inundate its riverbed, we also reduce the risks that may be incurred by flooding.

Illustration 9: © Ministry for the Environment, Korean RepublicAn example of fluvial restoration: the illustration goes from

the river in its natural state to its current, seriously damaged state, and ends with a possible scenario of restoration.

River restoration: towards a new pact with natureA re-evaluation of rivers focuses our attention on the reinstatement of ecological functions which contribute to the health of biodiversity, and, in the final analysis, contribute to our health too. The regeneration of a river can become the driving force of a new economic development of the land. Politics which value and invest in the long term management of water can prevent and regulate risks while giving value back to the territory through which rivers flow. This is a pact we must enter into with nature in order to live once more in harmony with the natural world. Over the last few years, two different re-evaluation approaches have developed, known as re-vitalization and re-naturalization . Fluvial re-evaluation has the potential to become a global phenomenon and bring about a different kind of economic development, one that can equal the phenomenon of expansion of a commercial company on the market.

Illustrations 10: © Centro Italiano per la Riqualificazione FluvialeSequence of restoration of a stretch of the river Drava

(Croatia). The effects are already visible in just a few years.

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Illustrations 11: © OFEFP, BernaRegeneration of rivers: the example of Moesa (Switzerland).

Re-vitalizationIn re-vitalizing a river, we attempt, wherever possible, to reinstate the natural conditions of the water’s pathway, keeping water usage to a minimum, therefore increasing the quantity of water in the river itself. This approach foresees the reduction or even elimination of interruptions created along its course, like dams or cement banks. Doing this allows for an increase in the transportation of gravelly material and recreates alluvial bands within which the river can freely expand. This approach favors the natural flooding mechanisms of a river, with the creation of areas of control where the river in flood can expand in total safety.

Re-naturalizationRe-naturalization has a slightly different objective, and that is to increase the levels of naturalness in the vicinity of rivers, promoting the creation of new vegetation or recreating swamps and humid areas which will enhance biodiversity. The intervention required here is not as radical as that required for re-vitalization, but rather takes into account the most recent evolutionary dynamics which characterize a territory. In order to reinstate the correct balance between humans and rivers, environmental and ecological knowledge must be integrated with social and local economical factors. Only by considering a river in its entirety from source to mouth as an “organic unit” can optimal conditions be attained which will result in both the satisfactory ecological state of the water and truly sustainable development in the long term.

So what can you do? Adopt a river!If you want to carry out your own evaluation of a river near your home, there are several methods you can use, based on field observation. Here below you will find one of the simplest of methods, which you can then look into in more depth with your teacher. Here is what you should observe:1. The area in which the river flows. Observe the context

in which the river flows, evaluating nearby features like

houses, factories, fields, etc, and what strains there are on the river’s course.

2. The course of the river. A straight, rectilinear course means the river has fewer self cleansing properties, because straightness reduces the possibility for retention and accumulation of material. A curved or meandering river is more natural and helps reduce the dangerous consequences of flooding.

3. Human activity. You should look at whether there are human works and structures along the banks or within the river itself which interrupt the natural flow of water or which artificially separate the river from the surrounding land (cement banks).

4. River vegetation. The vegetation is extremely important and you should evaluate how many plants there are (excluding the vegetation that is at a distance from the banks or shores) and if they occur in a continuous manner.

5. The depth of the water. Even if this is more difficult to evaluate, we should be aware that a non homogeneous river bottom helps the flow of the water and increases its ecological capacity, particularly important for the life of fish.

6. The river bottom. It is important to look out for the existence of rocks and stones, because the more varied a river bottom is, the greater the number of habitats favorable to animals and plants there will be.

7. Algae and film on stones. In order to evaluate the quality of the water, we can look at the subtle film that forms on stones. This film becomes thicker and more visible (also due to the presence of invasive algae) when polluting substances are poured into the river.

All the foregoing considerations must obviously take into account the specific characteristics of the territory in which the river flows, because different regions have different types of rivers. Each single river is shaped according to its territory. The criteria listed above are only indicative but they can certainly help give you a general idea of the quality of a river. You should then check your findings by referring to a good book which deals specifically with the river you have chosen to adopt!

Dossier compiled by:

Water Civilization International Centre, Venice:www.civiltacqua.org

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References

Abramovitz J.N. (1997). “Valuing nature’s services”. State of the world – Progress towards a sustainable society. Worldwatch Institute Report.

Barbier E.B., Acreman M.C., Knowler D. (1997). Economic valuation of wetlands: a guide for policy makers and planners. Ramsar Convention, Gland.

Brierley G., Fryirs K. and Hobbs R. (2008). River Futures: An Integrative Scientific Approach to River Repair, The Science and Practice of Ecological Restoration Series, Island Press.

Darby S. and Sear D. (2008), River Restoration: Managing the Uncertainty in Restoring Physical Habitat, Wiley & Sons Ltd.

ECRR (2008). Addressing practitioners, Lelystad, Evers Productions.

Gumiero B., Rinaldi M. and Fokkens B. (eds) (2009). Proceedings of the 4th International Conference on River Restoration, Venice.

Maltby E., Holdgate M., Acreman M.C., Weir A. (1999). Ecosystem management; questions for science and society. Sibthorp trust.

Seyam, I.M., Hoekstra A.Y. and Savenije H.H.G.(2001). Calculation methods to assess the value of upstream water flows and storage as a function of downstream benefits, Value of Water Research Report Series No. 10, UNESCO-IHE, Delft, The Netherlands, www.waterfootprint.org

UNESCO (2009). Water in a Changing World, The United Nations World Water Development Report, n.3, World Water Assessment Program, UNESCO Publishing – earthscan. www.unesco.org/water/wwap/wwdr/wwdr3/pdf/WWDR3_Water_in_a_Changing_World.pdf

Van der Zaag P. and Savenije H.H.G. (2006). Water as an economic good: the value of pricing and the failure of markets, Value of Water Research Report Series No. 19, UNESCO-IHE, Delft, The Netherlands, www.waterfootprint.org

Zalewski M., Janauer G.A., Jalànkai G. (1997). “Ecohydrology – A new paradigm for the sustainable use of aquatic resources”. International Hydrological Programme, Technical Document on Hydrology No. 7. UNESCO, Paris.

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