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LIBRARY

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Index

LIBRARY..................................................................................................1

INTRODUCTION......................................................................................4Rivers and water.............................................................................................4

Water environments........................................................................................4

Human development and sustainable management of natural resources......5

Preface to the use of Library...........................................................................6

CHAPTER 1: MODIFICATION OF THE SYSTEMS................................7Human landscape...........................................................................................7

Regulation and other works on rivers.............................................................8

Protection of water ecosystems......................................................................9

Legislation.......................................................................................................9European legislation........................................................................................................10

Water Framework Directive (2000/60).............................................................................10

CHAPTER 2. RIVER ECOLOGY (*).......................................................12River morphology..........................................................................................12

River-bed.........................................................................................................................12

Transportation of material................................................................................................13

Erosion.............................................................................................................................14

Sedimentation..................................................................................................................14

River dynamics..............................................................................................14

Human works and the effects on the river....................................................15Breaking of the banks......................................................................................................15

Interruption of the continuity between the river and the surrounding area......................15

Waterproofing of the river-bed.........................................................................................16

Fauna............................................................................................................16Macro-benthonic communities.........................................................................................16

Ecological zoning.............................................................................................................17

Graziella Mocellin - Maria Pia Coceano / ISIS Malignani

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Jegger II, 16.03.10,

Update, some headings were corrected!

Flora..............................................................................................................18Aquatic vegetation...........................................................................................................18

Riparian vegetation..........................................................................................................18

Role of vegetation for the river equilibrium......................................................................19

CHAPTER 3. WATER RESOURCE (*)..................................................20The presence of water on the earth..............................................................20

Hydrological cycle............................................................................................................20

Physical qualities of water...............................................................................................21

Chemical qualities of water..............................................................................................22

Water and life...................................................................................................................26

Photosynthesis................................................................................................................27

CHAPTER 4. MAN’S USE OF WATER (*)............................................28Agricolture (*)................................................................................................28

Water consumption..........................................................................................................28

Water pollution.................................................................................................................29

Industry.........................................................................................................29Water consumption..........................................................................................................29

Water pollution.................................................................................................................29

Civil use.........................................................................................................30Pollution and potable water.............................................................................................30

Water purification.............................................................................................................31

Water consumption..........................................................................................................31

Rivers: not only water ...................................................................................33Rivers as lines of communication ...................................................................................33

Culture and recreation.....................................................................................................34

BIBLIOGRAFY.......................................................................................34

Index of figures.......................................................................................35


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INTRODUCTIONNotes to the text: the underlined blue words are available in the Glossary tool of FYR platform.

Rivers and water

A river is like a living “organism.” It is a complex system of plants, animals, nutrients, movement, and

habitats. It includes all the living organisms of the entire basin, from the small aquatic beings

(bacteria, algae, larvae, shellfish, and fish) to the larger terrestrial vertebrates (reptiles, amphibians,

mammals, and birds) and humans.

A natural-flowing river creates abundant habitats which host a great number of living species. The

variation in the waterscape (environmental differences) enables the river to shelter a large number of

living species: for a river to keep its normal balance and to perform its natural functions, environmental

diversity and biodiversity are fundamental conditions. One of the most important functions of the river

is its self-cleansing ability , that is to saywhich refers to the mechanism,process in which micro-

organisms, macro-invertebrates and vertebrates literally break down both natural and human-created

organic and inorganic waste in the water and purify the riverine environment.

Water is essential for life and for the survival of all creatures, and therefore, the management of this

precious gift is one of the greatest challenges of our time. As the demand for water spirals upward,

the inevitable need for adequate supply networks and sanitary services must be satisfied.

The distribution of fresh water reserves (supply) on the earthour planet is unequal: many regions are

subject to flooding in particular periods of the year, while other regions suffer from frequent drought

periods. The consumption of fresh water is likewise unequal: it borders on waste in rich countries, and

it is under thea limiting factor ofor survival in poor countries. At present 80 countries and more than 1

billion of the world’s population lack access to potable (suitable for drinking) water. That statistic

meansThese figures also indicate that 40% of the world’s population suffer from lack of fresh drinking

water. The consequence of this painful situation is, as the World Health Organization affirms, that

millions die every year because of lack of water or bad water quality.

Water environments

The presence of water strongly influences life on our planet. This is not only because water represents

a vital element for all life forms of life on earth, but also because it creates environments such as

rivers, lakes and wetlands which, in turn, constitute natural habitats for an enormous variety of plant-,

and animal species.

Graziella Mocellin - Maria Pia Coceano / ISIS Malignani 5/38

Vegetation in marshes and ponds is distributed in relation to the depth of the waters: as one moves

from the centre of a water body (e.g. a pond) to the outer edges of the riparian zone, populations of

plant species change and blend from one into another. Thus, over in a small area one can observe an

exceptional variety of habitats which is also the reason that moist, damp areas are characterised by

such high biodiversity.

Rivers are ecosystems which not only includeare characterised by the flow of water itself (as an abiotic

factor), but also as well as by the sum of all organisms within the river basin (biotic constituents). A

river is an ecological continuum of environments that can differ from one to another, and it functions

best when there has been little or no human intervention on the part of man along the river-bed and

flood areas.

In Europe very few rivers are free to flood (e.g. the Loire in -France). Luckily, in other regions of the

world there are more numerous rivers which, at least in part, still experience periodical inundations

leading to temporary, wetland habitats like damp prairies, grassy swamps, alluvial forests, or stretches

of water formed out of abandoned meanders.

Lakes are formed whenever there is a depression of the ground characterised by a waterproof

substrate or by one which, in any event, does not possess good drainage. Most of the lakes in Europe

are permanent, freshwater lakes. However, in Southern Europe where there is a more Mediterranean

climate or in the regions of the former Soviet Republic Union salty lakes (even temporary ones) are

very widespread. Along the shallow lakesides light penetrates easily to the bottom and enables the

development of rooted plants which create the biologically rich transition-zones between the stretch of

water and the dry land.

Human development and sustainable management of natural resources

The availability of natural resources, especially water, has a strong influence on human society., and

tToday water is one of the biggest obstacles to development in many countries. This is demonstrated

byHistory illustrates the often historical, close and dramatic connection between the lack of drinkable

water and the level of poverty in a country.

Water is not only essential for human health and quality of the life, but also for the development of

communities, for agriculture (farming and breeding ), and industry.

Now at the turn of the century, the state of the eEarth’s water reserves are is quite alarming:

population growth, natural resource use and increased consumption have almost exhausted available

water resources. The symptoms of this dramatic situation have been unfortunately been

underestimated for too long: water has been considered a free inexhaustible gift, and it has been

wasted and used inefficiently. Water resources, even in countries with plenty of water, are endangered


by pollution, overbuilding, increased consumption, irrational exploitation of resources, unsustainable

economic growth and climatic changes.

Today, rivers risk becoming the symbol of the effects of man’s alteration of the environment: rivers are

blockaded into reservoirs and forced into channels to create water supplies for agriculture, industry,

public uses.; Rrivers are attacked threatened by pollutants and by development along the banks and

the beds, and ravaged by the scarce and inefficient maintenance of river beds.

Theise entire alterasituations will inevitably result in the alteration of have an effect on the natural

balances of many rivers with many negative consequences for animals, plants and man, which all

depend on itthem.

Solutions are not simple, but it is clear that increasing our effort to build dams, embankments and

deviations on rivers is not the best way. An alternative existsHowever, there is an alternative: the

sustainable management of fresh water resources, which is to say. In other words,: maximizing their

rivers’ benefits and, at the same time, preserving the natural processes, which to guarantee the long

term enjoyment and use of water resources.

Figure 1: EU Water framework Directive campaign (Italian version)

Preface to the use of Library

The aim of the following chapters aim is to provide support and background information and deepen

the understanding of the relevant points related to freshwater and river management, especially where

these related toconcern the checklist planndesigned by the FYR project tofor assessing a river quality.


Each part of the Library is related to one or more chapters of the checklist developed by FYR to

monitor the water/river situation. Evidence of that is given in order to guide teachers/students in which

part of checklist they could choice along their project.

In the text, any reference to the specific questions (indicated with bold letters) to the specific

questions is highlighted, in order to define give a better overview of the correspondence between the

text and the work toing plan.


CHAPTER 1.: MODIFICATION OF THE SYSTEMS

Human landscape (*) (*) related to the LANDSCAPE chapter of FYR Checklist

Landscape is the combination of the visible features of a place, a territory, it is the “view” that we

admire (question 1 of Landscape). Wetlands are the richest areas for showing the richest

biodiversity (questions 4-7-8-14-15).

Figure 2: How wetlands work (www. beachwoodhistoricalalliance.files.wordpress.com)

Springs, rivers, lakes, streams, and marshes give shelter for many environmental processes. The

energy of water constantly shapes the land, creates the most varied environments, and provides

therefore habitats for a multitude of species. However, all the world estimates state that biodiversity of

freshwater is decreasing very quickly; the reason for this phenomenon is that man regularly modifies

and destroys freshwater and its habitats: draying of marsh lands, use of flood areas for agriculture,

canalizations and river diversions. (questions 2-3-5-6-9).

Man has always changed the environment to make it suitable for his settlements and to produce the

necessary natural resources for the community. Therefore, the analysis of a watershed looks at the

history of its environment as well as the history of the its people who have settled there. I: it shows the

way, the reason why, and the place where cities have first settled developed and, it explains the

choice to locate of many industries in a valleyto settle at typical locations within a watersheds in order

to exploit hydroelectricity or other resources the present rough material.



??

Regulation and other works on rivers (*) (*) related to the subchapters 4 (urbanisation), 8 (protection), 9 (restoration) of the

HUMAN USAGE chapter in theof FYR Checklist

Man-made works, which have beenare constructed on rivers (e.g. embankments) even till today, are

aimed at “controlling” rivers to enable the exploitation of the land around them for agriculture, housing,

and industry as well asnd tfor prevent flooding prevention.

Embanking, which is used to manage and exploit the waters of the rivers (question 4 a-b HUMAN USAGE), alters the natural morphology of the river and the outflow of the waters and increases the

vulnerability of the whole system. The large artificial hollows and the transversal works alter the

transport of solid materials and influence the methods of deposition; the basin is progressively covered

with sediments, which are blocked by the barrage that disrupts their flow, while the water and the soil

in the valley, without replenishment, isare then impoverished of needed minerals and top, which. This

can in turn lead to accelerated erosion. Barriers also obstruct the fish passage (question 4c) and the

water regulation trough barrages such as dams or locks causes variations of water level, which

consequently can destroy entire populations of nesting birds.

Figure 3 : aA watershed (www.recycleworks.org)

Dams, those which are barrages that create huge hollows from high water flows to hydroelectric power

plants through conduits, cause the worst damages on rivers and their surrounding regions.

Worldwide, huge manmade works are built and the diversion of entire watershed s modifiesy

irreversibly the landscape and the involved surrounding ecosystems irreversibly.


A new sensibility for river protections is fortunately appearing (question 4d), for example, in

restoration works (subchapters 8/9 all questions) to which aims at restoreing the “natural”

environment of the rivers as far as possible, and consequently their most important ecological

functions:

1. capacity of self-purification, with the subsequent reduction and prevention of pollution;

2. capacity of flood s control and reduction of hydrologic risk

3. environmental rehabilitation , through the restoration of the ecological continuity of the course of

the river.

However, it should be kept in mind that these are complex processes, and it will take years for the

entire river ecosystem to find againregain its balance.

Protection of water ecosystems (*) (*) related to the LANDSCAPE chapter of FYR Checklist

The loss of riverine environments exposes man to various risks. I; in fact, a healthy ecosystem can

control the effects of floods, avoid catastrophic inundations, and provide a constant self- purification of

waters.

Hence, tThe preservation of freshwater ecosystems is necessary to provide safety and a regular

supply of potable water.

Subsequently, it ensures as well as for food supplies and the hygiene of millions of people in the

poorest countries, who depends on rivers for fishing and, on wetlands for production of fooding food

and fibres. A This is a further reason to support the protection and management of water ecosystems

asis that they are fundamental for reducing poverty and sustaining the economy of many countries.

The decline in the health of the environment in most of world’s watersheds is demonstrated byseen in

symptoms such as the decrease of fish stocks, the variations in flow causingbecause of flooding and

drought, and the deterioration of the water quality.

Methods of sustainable management are necessary to preserve and restore the correct functioning of

rivers, lakes, wetlands, and flood areas., and tThis is the only way to ensure a steady supply of water

and to improve its quality. For this purpose, “natural approaches” exist, which are based on the

restoration of the environmental functionality of rivers and their territoryies (question 10-11-12-13 of Landscape): for example the restoration of humid areas, which act as filtering ecosystems, and of

vegetative riparian zones that not only act as buffers that reduce the presence of nutrients, but also

contribute to the improvement of the quality of the water.


(to deepen this topic see MORPHOLOGICAL ASPECTS Chapter of FYR Checklist)

Legislation (*) (*) related to the HUMAN USAGE chapter of FYR Checklist

European legislation

National or country-specific laws regulate the management of water resources (question 1d-e-f-h-i, 2 c-d, 4 d-e, 8-9 questions of Human usage); however, the European Community (EC) sets the

principles, through supra-national regulations, to which all the Countries must conform. The following

are some of these European dispositions about water: water quality for human consumption (80/778),

potable water (98/83), disposal of urban sewage treatment (91/271), protection of waters from

pollution caused by nitrates from agriculture and by dangerous substances from dumping and landfills,

and water quality standards for fish and shellfish.

Water Framework Directive (2000/60)

One of the most recent and significant EC regulations is the directive establishing a framework for

community action in the field of water policy (2000/60), which requires the protection of internal

surface waters, transitional waters, coastal and subterraneous waters. This regulation must be

implemented by optimising the use of resources and integrating the different regulations for water. A

management plan for every watersh ed in accordance with an environmental policy which considers

the water cycle rather than the administrative borders of provinces, regions, or states is the

fundamental requirement behind this legislation. ThereforeFurthermore, this regulation promotes a

sustainable use of water reserves, which is based on the long-term protection of available water

resources. It aims at avoiding risks to the health and safety of people (social aspect), provides an

efficient access of people and production activities to resources (economic aspect) and protects the

resources and maintains their environmental functions (environmental aspect and ground of fairness

between generations). The Member States are requested: to check the environmental impact of

human activities, to analyse the economic aspects of the exploitation of water, to monitor the surface

and underground waters and of protected areas, as well as to take the necessary measures to avoid

the deterioration of the water basins, and to involve all the parties concerned in this process (water

management).

With the Water Notes for implementation of the water Framework Directive, the EU Community

giveshas provided tools easy to read and to understand, about explaining the main guidelines lying

behind the Directive itself.

They are available at http://water.europa.eu/


Water Note 1: Joining Forces for Europe’s Shared waters: Coordination in international river basin

district

Water Note 2: Cleaning up Europe’s waters: identifying and assessing surface water bodies at risk

Water Note 3: Groundwater at risk: managing the water under us

Water Note 4: Reservoirs, Canals and Ports: managing artificial and heavily modified water bodies

Water Note 5: Economics in Water Policy: the value of Europe’s waters

Water Note 6: Monitoring programmes: taking the pulse of Europe’s waters

Water Note 7: Intercalibration: A common scale for Europe’s waters

Water Note 8: Pollution: reducing dangerous chemicals in Europe’s waters

Water Note 9: Integrating water policy: Linking all EU water legislation within a single framework

Water Note 10: Climate change: addressing floods, droughts and changing aquatic ecosystems

Water Note 11: From the rivers to the see: Linking with the new Marine Strategy Framework Directive

Water Note 12: A Common Task: public participation in River Basin Management Planning


CHAPTER 2. RIVER ECOLOGY (*)

(*) related to the MORPHOLOGICAL ASPECTS of FYR Checklist

River morphology

A river is an “environmental continuum:”: a series of small environments and ecosystems, that are full

of life and transition from one into another. There is a so-called longitudinal continuity from the

upstream to the middle reach to the downstream section of a river and a transversal continuity among

the river bed, the banks, and the catchments basin. The action (flow, erosion, etc.) of the river affects

the riverbed as well as the nearby landscape, which is called an “area of riverine pertinence,” which

also includes the natural riparian areas (low marshy lands, willow groves, alder groves, hydrophilic

meadows) along the river (question 2 of Morphological aspects list). In the natural environment of

the river, the passage from the aquatic to the terrestrial habitat is not sudden but it is gradual within the

riparian area. This area has important ecological functions because it provides a buffer zone for

nutrients (capacity of self-purification), an area of reproduction for fish, hydro-geologic regulation,

increased biodiversity, climate regulation, and habitats for amphibians, reptiles, birds, mammals and

many others (question 3-4).

River-bed

While crossing the river from side-to-side, one can recognize the ordinary river bed (the channel,

which is occupied by the river in periods of normal water flow), as well as the low-water channel and

the flood channel. The low-water channel has an indefinite and continuously reshaped pattern. On the

other side the flood channel (flood area) is usually low, often covered with vegetation or cultivated and

submerged during floods (question 5).

Hours after a strong rainfall, the flow of the river suddenly increases. At the beginning, water is

stopped by vegetation and percolates through the soil until refilling the aquifer, but when absorption

surpasses the limit and the soil is saturated, water begins to flow to the surface and toward the river.

This phenomenon explains the interval of time between the maximum rain and the peak flow.

Conversely, it takes less time for water to flow from the sides of a river to the main course, if

vegetation is scarce or even absent. In addition, during a flood, the increased flow and speed of the

water increases the capacity for erosion and transport of inert material (question 6).


Figure 4: rRiver morphology (Colorado water resources CSU)

Transportation of material

Water is a geomorphologic factor (related to the form of the surface of the Earth) : i. It sculpts the land,

erodes the substrate and creates new shapes. The substrate (the stone, the soil, the sides and the

river bed) offers passive resistance to the erosion of water and its course.

The water of a river has a power (the kinetic energy produced by movement), as do all moving bodies.

This energy is determined by the speed of the current and the flow . The friction from the deposits and

structures on the riverbed dissipate a large part of this energy, which creates turbulence, eddies, and

whirlpools, but the remaining energy is used to transport material towards the valley. The faster the

river is, the more quickly the energy increases, and the larger the amount of the transported materials

there is:. iIn the high slopes (usually streams), where the river is very fast, the material consists of

small pebbles.; i In the stretches with a slight inclination (usually in the plains), where the river is slow,

sand and silt are constantly transported. They can be carried by in suspension, which is the case for

especially fine material, for over long distances, or by rolling along the riverbed as is the case for

rough material.


During flood ing a river’s flow and speed increases considerably, as well as its capacity to transport

material in a particular stretch. This capacity is seen by the amount of material, or sediment, which is

suspended in cloudy, turbid water and which gets caught in bridges, barriers, etc….(question 7)

Erosion

Energy that is not dissipated by friction and transportation, erodes other material from the substrate.

Mechanic erosion in the river-bed is mainly caused by the abrasive capacity of the transported debris.

Water acts directly on the river-bed (linear erosion) and on the whole basin (widespread erosion),

especially on inclined and barren surfaces. The mechanic action of water on the substrate is

important, as well as the action that solubilizes the mineral salts of the rocks and the action related to

the alternation of frost and– thaw (question 8).

Sedimentation

In stretches where the river is slower, the capacity of transportation changes. Transportation levels

may drop, F for example, because of a sudden decrease in inclination, or because of higher dispersion

caused by friction with very rough ground., transportation levels may drop. First, the rough and heavy

material sediment s out , while the fine material is carried along until it is “dropped” on the riverbed.

Rough deposits form the upstream river bed. A; but as the river flows toward the valley, its bed

increasingly consists of smaller pebbles, sand, and silt (very fine deposits) (question 10).

River dynamics

The river is a dynamic system, which is constantly changing,. and iIt shapes its course as well as the

land it crosses, and leavinges its typical marks. The valleys, where a river erodes and digs its course,

are shaped like a “V”. The sides of valleys, which are composed of hard rocks, are not subject to

widespread erosion but to linear erosion (that is the erosion of the course itself), which produces deep

valleys, gorges and canyons with vertical walls.

In others areas, the river does not erode, but rather transports and deposits fine material,. tThis way it

produces alluvial plains and terraces, levelling the V-shaped valleys and filling them with sediments.

and levels the V-shaped valleys.

If we observe the mechanisms of erosion – transportation – sedimentation, we can better understand

the way a river shapes its course and the territory it crosses and the way any intervention on the river-


bed changes the profile of the river., which starts from a spring and flows toward the sea or a

confluence.

This profile, which starts from a spring and flows toward the sea or a confluence, is dynamic,. It is

determined by the balance between erosion and deposit ion of material , especially in the mountain

stretches with steep slopes, and is changed with external disturbance. , and is determined by the

balance between erosion and deposit of material, especially in the mountain stretches with steep

slopes. A flat river is a good example of sedimentation where the slope is gentler, the flow of the river

is slower and the course is winding.

The meanderings of a river (question 11) result from the combined action of sedimentation and

erosion: the external concave bank is quickly eroded and becomes steep. The eroded material from

the concave bank deposits on the internal side of the meander, because the current cannot bring into

suspension all of the materials in this area. A bank with a gentle slope is formed in this internal convex

side. This way, the meanders tend to become more and more pronounced, because the combined

action of erosion and sedimentation becomes a constant process once, when it is started. When a

curve is too marked, the river can skip a meander and go back to a linear course, because the curve is

torched.

Human works and the effects on the river

The riverine environment can be seriously damaged by direct works on the river-bed (artificial banks,

excavations in the riverbed, barriers, dams) or by the cultivation and urbanization of the natural flood

areas, which often remove or reduce riparian forests and wetlands (question 1).

Breaking of the banks

If the embanking works alter inappropriately the banks, they can amplify the effect of the flooding.

Floods are common events, and they are essential to the evolution of the river-bed morphology. Over

time they find an equilibrium profile. Oftentimes, when floods create great economic loss and even

fatalities, they which could have been prevented if building was had been restricted in flood plains,

man-made alterations of the river had been were limited, and natural flood-prevention structures

(wetlands, riparian zones, channels) had been were left in place (question 9).

The water and the transported materials, which in a normal situation would disperse in the flood areas,

are forced to flow and settle in a dammed area. The material, which settles within the banks, causes



?


I moved some sentences around, pay attention to formatting the underlined words again (blue)!

the river-bed to rise, and the huge amount of water flows with an increasing erosive force. Breaking of

the banks and flooding is the likely result of removing the natural protection.

Interruption of the continuity between the river and the surrounding area

Besides increased flood potential, poorly designed flood regulation works can interrupt the continuity

and the exchange between the river and the surrounding environment, and reduce biodiversity, found

within a wild healthy river. Without trees on its banks, bends, rocks or ponds, the river is forced to flow

along a constricted channel. These natural elements are able to shelter a large variety of animals and

plants. Hindering the natural development means limiting its capacity to create habitats and

consequently to shelter certain species. In addition, the loss of biodiversity reduces the self-purifying

capacity of the river, compromises the entire river ecosystem, and makes it more vulnerable to

stressfuling conditions (e.g. polluti n on g and waste water discharges).

Overall, when altering a river’s profile and making it is made uneven by dams or barrage barriers,

blocks theit natural transport of material (sand, gravels and pebbles), hinders the movement of aquatic

species, and endangers their survival (question 9-10).

Waterproofing of the river-bed

The waterproofing effect is another risk of concreting the river banks and the same riverbed. This

produces a real waterproofing effect on the river and limits or even completely stops the natural

exchange of water with the riparian area and the ground-water table (aquifer) which is found below

and along the sides of a river. The difficulty or the interruption of this exchange can result in the

biological death of the ground-water table and consequently the death of the numerous organisms that

live there and provide self-purification functions. Besides, as a result of an isolated ground-water table,

the water flow is reduced and it is no longer able to work as a balancing element. In natural

conditions, during floods, the ground-water table receives water from the river and in this way

decreases the river’s flow and flooding. On the contrary, during low water conditions , the ground-water

table gives water back to the river. Therefore, the proper functioning of this natural water-exchanging

mechanism reduces the effects of floods and assists during low water conditions, which serve to

benefit both man and all other living organisms within the river system and man .(question 9-10).

Fauna

In a healthy river environment, communities of animals and plants are born and grow, feed, breed and

die in close link with one another (producers, consumers, decomposers). The whole of living

organisms (bacteria, algae, larvae, shellfishes, fish, etc.…) within the water, in the substrate and in the

banks forms the ecosystem of the river. The river is not an isolated, self-sufficient ecosystem however,

and in fact, it receives inputs from the surrounding environment: for example the mineral salts in the


water and the vegetal and animal wastes are the first sources of nourishment for invertebrates, or the

small insects on which fish, birds and terrestrial mammals depend (question 13-14).

Macro-benthonic communities

Each stretch of the river houses a well-organized biological community. In particular, the macro-benthonic communities (“macro” = visible to the naked eye and “benthonic” = living on the ground of

the river) are formed by small organisms, which attach themselves to the riverbed and draw

nourishment from the water that flows over them. When water quality worsens, sensitive species are

the first to disappear (Plecoptera) and are then followed by the others (Efemenoptera and Tricopterra).

However, during poor water quality conditions, the strongest species survive (Diptera or Oligochaeta)

and even proliferate in this non-competitive environment. The composition of these communities

varies according to water quality: it varies from the optimum condition, where all of the locally-found

species thrive, to the most damaged condition, where only a few the strongest species among the

strongest ones can survive.

Organisms, that indicate the quality of the water by their presence or absence, are called bio

indicators.It should be noted that not every species single one of theof macro-benthonic species lives in every

water body. It should also be stressed that a varied macro-benthonic community often utilizes all the

nourishments in the river, is more adaptable to changes, and therefore can perform a better self-

purifying function . (to deepen this aspect go to Biotic Index).

Ecological zoning

Ecological zoning describes the different communities of organisms, that live in different stretches of

the river, and adapt to the different environmental conditions.

In the mountains or in sloping stretches the current is fast, the waters are turbulent, and rocks,

pebbles , sand and mud form the substrate of the river. The water is well-oxygenated and cold. The

organisms here are easily adaptablewell adapted to life in cold and well-oxygenated waters. The

stones on the riverbed are often covered with algae and give refuge to numerous larvae (Ddiptera,

Eefemenoptera, Pplecoptera and Ttricoptera), which use their suckers and legs with hooks to cling to

the substrate. The dominant fishes are the trout (S s almonoid) and greyling (Tthymallidae). This stretch

of the river is called Rhitron or salmonoid region (question 14).

In the low-lands or plains with less slope, the flow of the water slows down and the river-bed is wider,

the lighter sediments settle out, and the ground is formed by sand drifts and mud deposits. The typical

organisms found here, easily tolerate changes in temperature and survive with low concentration s of

oxygen. The water is often turbid because of the suspended material that is transported ; the large

quantities of dissolved mineral salts and the slow current allow the growth of plankton and immersed



Fish?


You start with capital letters for proper names here, do stick with it!

vegetation to grow (mMyriophyllus, dMuckweeds, cCrowfoot). The presence of this vegetation gives

shelter and food to many other organisms (shellfish, annelids). The dominant fish are the Ccyprinids.

This stretch of the river is called Potamon or barbell region (named after the dominant fish species).

Other very common fish species include carp, tinch, perch, pike, eel and the char in high altitudes.

Wetlands, or moist environments, are essential for the survival of amphibians such as green frog,

salamander, tritons and the yellow-bellied toads as well as many reptiles. Here many bird species

build their nest (wild ducks, water hens, herons, etc.), spend their winter and stop during seasonal

migrations (the tufted duck, the grey heron, the spoonbill duck, the cormorant). The presence of so

many living creatures attracts predators such as the brown kite, the duck hawk and the hen harrier.

There are also rare reptiles and mammals found here such as the otter, which now has only survivesd

only in verya few wild rivers.

Flora

The river has two types of vegetation: strictly aquatic ones flora that liveflourishes in or on the river-

bed, and riparian floraones that grows along the banks

Aquatic vegetation

Most of the aquatic flora consists of algae and taller plants, suited for humid environments and

sometimes even complete immersion, even if they are immersed only temporarilyy (question 12).

Aquatic plants depend on the riverine environment and their existence is influenced by many factors.

For example, periods of submersion, the aquifer level, the force of the current, the composition of the

riverbed and the transparency of the water, all play a role. Some plants are completely submerged,

while others root in the riverbed and emerge from the water at various heights, and yet others are

without roots and float on the water altogether.

In stretches of the river, where the water flows with force and speed, the plants are sparse,. Tthe

riverbed is instable and moves continuously, and only a small community of algae is able to colonize

(question 10). Some of these algae are microscopic, the Ddiatomeae and the cCianoficeae, and form

a coloured films on the substrate (e.g. the rocks). Where the current reduces its speed and the water

is calm, different species of algae, also again floating algaetypes, andas well as higher plants such as

cCrowfoots, proliferate.

Riparian vegetation

Riparian vegetation includes shrubs and arboreal species (reed beds, willows, alders, poplars), which

are found in areas between aquatic plants and other plant species, farther away from the river. They

are hydrophilic species, whose roots are connected with the ground-water table (aquifer).



The format extends over the space? Try to take the blue line out at the end of the word. This happens in several places, I only comment it here


Italics inconsistently used! Choose all italics or none at all

The riparian forests, or alluvial forests, generally are those wooded areas suited to moist soils that

cover both the river banks and the areas periodically submerged by flooding..

In the mountains, riparian vegetation principally consists of humid meadows which are gradually

replaced by riparian woods of alders as the slope of the ground decreases. Various species of willows

(Wwhite Wwillow, Rriparian Wwillow) and poplars, which prevail on the valley floor or plain, slowly

replace the alders. A rich underwoodgrowth, which is characterized by grasses, bushes, reed beds,

and sometimes orchids, grows besides the riparian woods (question 2).

Role of vegetation for the river equilibrium

Aquatic plants almost totally depend on the river water for their nourishment and survival, and so they

effectively reveal its chemical, physical and biological alterations. For this reason they are bio

indicators, together with the macro invertebrates.

The role played by this kind of vegetation, is fundamental for the balance of the river: the zone of

riparian vegetation works as a filter and therefore plays a key role in the purification of the water.

Through their roots, aquatic plants are able to absorb the inorganic pollut ants ing inorganic materials

such as phosphates and nitrates which are found in detergents (soap, laundry detergent, etc.) and

fertilizers that, which are increasingly used in agriculture. Because of this reasons a “buffer” zone of

natural vegetation between the rivers and the farmlands is extremely important.

Roots from these plants play another important function: they preserve the river banks from water

erosion. Alders and willows, for example, have large and deep root systems, which consolidate and

make banks resistant to the force of the current.

Vegetation found along the course of the river, often called a the “green corridor”, provides the shade

necessary to keep the water temperature stable. Water temperature influences the amount of

available oxygen dissolved in the water on which aquatic life forms depend (question 3-4).

As wellFurthermore, the variety of vegetation is able to give refuge and sustenance to many species of

animals, insects, birds, reptiles, and amphibians.

Thus, these bordering areas between water and land have a great ecological value. The riparian

zones, when intact, cross and link the land with the river, which serves as a biological corridor, which

and is vital for the vertebrate and invertebrate fauna. Unfortunately, these important areas have been

severely reduced and fragmented for reasons of development for housing, roads, bridges and

buildings;, flood regulations, and the desire for new and better farmland.


CHAPTER 3. WATER RESOURCE (*)

(*) related to the WATER QUALITY chapter of FYR Checklist

The presence of water on the earth

The presence of water is one of the most important characteristics of the earth. Water is present in

oceans, on continents and, in the atmosphere., and i It constitutes the element that connects

environments, and all plants and animal organism s .

Within the hydrosphere, that which is all of the water available on the planet, only 2.5% is freshwater.

Out of this small percentage, 69% is made up of ice or snow in the mountainous regions and in the

Arctic and Antarctica, 30% is beneath the surface of the earth and barely 1% of all fresh water is easily

accessible to man because being available in river s and lakes (Source: UNEP, United Nations

Environment Programme).

The distribution of water on the planet is neither constant in time nor is it uniform. In the past, polar ice-

caps have been seen to expand and shrink over time so as to modify sea-levels and the profile of the

emerged landscapes. Today, we observe areas that are extremely rich in water, such as the sub-

equatorial regions that host the greatest forests and the major rivers of the world, and conversely, we

witness others where water is particularly scarce.

Hydrological cycle

Figure 5 : tThe hydrological cycle (www.sawater.com)



Think this is the noun

The amount of water on the earth does is not subject to variations; however, its distribution can

change. Water changes its distribution between the liquid form (oceans, lakes, rivers, wetlands), the

gaseous state (water, vapour), and the solid state (glaciers and ice-caps) due toin the hydrologic

cycle. This is, one of the most fundamental natural processes and that has been occurring on our

planet for millions of years. It is a dynamic mechanism that causes constant changes owing to energy

from the heat of the sun and through terrestrial gravity. Water evaporates from basins (rivers, lakes,

oceans), from the soil, from the leaves of plants and is then transported as gas into the air. With

lowering sinking temperatures, the vapour condenses and changes into a liquid state. The water then

returns to the earth as rain, hail, or snow and falls directly into water basin s or into the soil from where

it will be channelled - also subterraneously - into the rivers and oceans.

Physical qualities of water

Water is a substance with which we have much familiarity. It is present on our planet in the three

typical states: solid, liquid, and gas. The liquid form is present within the oceans, the lakes, the rivers

and in aquifers. , t heIn its solid form it appears, as ice or snow, in the ice -caps, as well as in

mountain glaciers. In its, the gaseous form (or better: the as water vapour) it is found in clouds and

steam. The passage from one state to the other occurs under the influence of temperature

variationchanges, between 0° and 100° C.

A water molecule consists of one atom of oxygen (O) and two atoms of hydrogen (H). Water

molecules are bound to one another with the strong hydrogen bonds between oxygen and hydrogen

atoms belonging to different molecules, but close to each other.

Evaporation and condensation

Evaporation is the passage of water from the liquid state to the gaseous state. Water changes into

vapour when the thermal movement breaks the intermolecular bonds so that molecules are free to

move independently: they depart and evaporate upward. Such transformation is influenced by several

factors like temperature, humidity, evaporation surface and wind. While evaporation occurs only on the

water surface, boiling is different in that it involves all of the liquid mass and takes place only at the

temperature of 100°C ( if the pressure is 1 atmosphere).

Since a fairly high temperature is necessary to boil water, most of the water on earth remains in a

liquid state throughout most seasons and in most regions.

Condensation, finally is the process whereby water changes from a gaseous to a liquid state. As solar

heating causes the evaporation of the surface water of oceans, rivers and lakes, the newly formed



Try and join this with the line

vapour travels higher, transported by upward currents, in the atmosphere and is in turn cooled and

transformed into a liquid that then returns to the ground in the form of precipitation.

Freezing

The process of solidification or freezing represents the transformation of water from its liquid state to a

solid state (ice) and this occurs at 0° C. At this temperature water molecules create a crystalline grid,

made up of hydrogen bonds, granting stability and shape to the ice cube. But water presents a truly

unique characteristic which distinguishes it from all other existing substances: in fact, at temperatures

close to the freezing-point, and in particular around 4° C, water reaches its maximum density. Up to 4°

C water behaves like all other substances: its molecules draw closer, thus reducing inter-molecular

spaces and causing the volume of the mass of water to decrease whilst its density increases. Below

this temperature level, however, molecules can not approach each other even any more., o On the

contrary, they begin to draw further apart because of the hydrogen bonds keeping them in a rigid

structure. This characteristic has repercussions that we can witness in nature, for example in the case

of icebergs. Icebergs are true and proper mountains of ice which, owing to their lower density, are able

to float on water. Hence, water density levels are at their highest, not when the element becomes

solid, but at its liquid state.

Figure 6: Structure of hydrogen bonds (source: Wikipedia)

An additional aspect of water that bears great relevance on living-

beings is its ability to absorb, and give off heat without causing abrupt

changes in its own temperature (specific heat). This means that our

body, which consists largely of water, is capable of moving from hot

to cold environments, and vice-versa, while maintaining a constant

body-temperature. For this same reason, water plays a key-role in the

climate of coastal zones and around lakes. So it isThat explains that how seas and lakes absorb heat

during the warmer months withand yet the water temperature remainings cooler than the emerged

surface temperature of the surrounding land masses. Conversely, during the winter months, water

bodies mitigate the low temperatures by giving off accumulated heat.

Chemical qualities of water

Hydrogen bonds and polarity

Water is an inorganic substance and it represents the most essential element for life on our planet.

The water molecule (H20) is composed of three atoms – two of hydrogen (H) and one of oxygen (O).

Because the two electrons which are responsible forinvolved in the bond between hydrogen and

oxygen tend to spend more time in proximity of the oxygen, rather than the hydrogen, the oxygen atom



Same here

ends up being partially negatively charged, while the hydrogen will be partially positively charged. This

leads to the consequencetly thatcauses the water molecule presents an important characteristic of the

water molecule: its polarity. A “polar” substance is a substance with two poles: + and – (like batteries).

Figure 7: Polarity of water molecule (www.daviddarling.info/encyclopedia)

When another polar substance is mixed with water, the poles of the different molecules are attracted

to each other and the substances blend. Thus polarity determines the solubility of a given substance.;

it is water-soluble if it dissolves in water. Water-soluble substances contain polar or ionic bonds.

Electric polarity and hydrogen bonds are responsible for the chemical-physical properties of water.

They are essential for biological processes which require the dissolving of a vast varietiesy of ions and

molecules, larger or smaller.

All those molecules that are capable of forming hydrogen bonds will be soluble and are known as

“hydrophilic”. Molecules that do not possess this ability will generally not be soluble., t These are

referred to as “hydrophobic”.

Water is an excellent solvent for mineral salts, but also for organic substances like saccharose. In

nature water can not be found in a chemically pure condition. Even spring water in fact contains other

substances dissolved in it: it is a solution. Clean rain water (non polluted), one of the purest types of

water, contains small amounts of carbonic acid, produced by reaction with carbon dioxide, and nitrous

oxides produced by thunderstorm phenomena. But rain can also react with substances produced

through the combustion of carbon and petrol, such as sulphur and nitrogen oxides. This, in turn, is at

the origin of the phenomenon of acid rain which causes severe damage to forests and aquatic

ecosystems in various regions of the globe, included some areas of Europe.

pH

Water has a slight tendency to ionize, which means it forms positive H+ ions (hydrogen) and negative

OH- ions (hydroxide). In pure water the number of these ions is equal and water is said to be neutral. If

positive ions prevail the solution becomes acidic and if negative ions out-number the positive ones, it

is referred to as an alkaline solution. pH is the term used to express this relationship between the two

types of ions. The pH scale measures values usually between 0 and 14. Up to pH= 7 a solution is

considered acid, between 7 and 14 it is alkaline, and at pH =7 it is neutral. One should bear in mind

that the chemical reactions of living systems occur within restricted pH limits which are usually around

the neutral level. Water meets this requirement of neutrality through another of its characteristics,


alkalinity, which permits it to neutralise acids and alkali and to prevent the water’s pH-level from

varying.

Solubility of salts

As mentioned before, polar or ionic substances can be dissolved into water, but the dissolved amount

ivaries very different for each substance. The maximum amount of a solute that can be dissolved in a

given quantity of water (solvent), at a fixed temperature, is called solubility , and the solution obtained

is called saturated solution. If we add more solute, it will precipitate and be visible at the bottom of the

container in the solid form.

Many types of substances are water-soluble and can be found in surface waters, but among them

salts are the most important ones. They are classified as soluble, insoluble, and slightly soluble

(respectively at least 0.1 moles per litre at room temperature, less than 0.001 M at room temperature,

or between these extremes). Salts in freshwater are the result of dissolving processes of rocks and

soils where waters flow through, and they determine water

hardness.

Salts are composed by of positive and negative ions, forming strong

ionic bonds in their solid form.

Figure 8: Ssolid form of a salt (www.bbc.co.uk/.../ionicrev3.shtml )

Figure 9: Pprocess of dissolving

When they salts are put into water, however the ions are surrounded

by water molecules and separated from each other. In this wayHence

they can move around in the solution, giving it the property to conduce

electricity (electrolytic solutions). In this form salts are and making

available to roots, providing the elements essential to plant growth.

Plants require three major nutrients for growth: carbon (captured from CO2 of air with photosynthesis

process), and nitrogen and phosphorus ( , available to plants as dissolved ions).

NITRATES (NO3-). Nitrogen is present in water in many forms, but nitrate is usually the most important

inorganic form, because in this form it is captured by roots and used for growth and reproduction inof

many algae and aquatic plants. Nitrates are soluble salts. , tTherefore, human activities can greatly

affect their amounts in water bodies. Pollutants such as sewage or manure, wastewater treatment



Source?


Formatting: align with tab of top paragraph if possible

http://www.bbc.co.uk/.../ionic

plants, runoff from fertilised lawns, cropland, animal manure storage areas and industrial discharges

are all sources of nitrates and responsible forof the increase of NO3- their concentrations in water

bodies. Scientists often call nitrogen a “limiting nutrient” because in low amounts, plants use up all the

available nitrogen in the water and cannot grow or reproduce any furthermore. However,Aan excess of

these salts is responsible for eutrophication. Normally, levels of nitrate range from 0 to 10 mg/L are

found. Nitrate usually is found in nature in very small amounts because of the ongoing growth and

decay process. When plants and animals die and decompose, ammonium (NH4+), is produced.

Bacteria usually turn the ammonia into nitrite (NO2-) and nitrate (NO3

-).

PHOSPHATES (PO43-). Phosphorus is present into waters in various forms, soluble or often trapped

in sediments. The latter, that must be converted into the phosphate its soluble form (PO43-) to be

measured. As for nitrates, scientists call phosphorus a “limiting nutrient” because in low amounts,

plants use up all the available phosphate in the water and cannot grow or reproduce anymore. The

number of aquatic plants growing in a particular area is dependent on the amount of phosphorous

available. Most natural waters have phosphate levels under below 0,2 mg/L phosphate, but

concentrations over 1 mg/L phosphate are found in some areas. Phosphates can be found in water in

three different forms: orthophosphate, metaphosphate (or polyphosphate) and organically bound

phosphate. Each compound contains phosphorous in a different chemical formula. Phosphates can be

trapped into in sediments, as its salts have often a low solubility. Organic phosphates, which are part

of living plants and animals, are introduced into the environment naturally and from human activities

such as: human and animal waste s , fertilisers, industrial wastes and human disturbance of the land

and its vegetation. Phosphates are produced by natural processes of decomposition of organic matter

and are found in sewage. Poly-forms are used for treating boiler waters and in detergents: they are

important in nature and they can change into the soluble form.

Eutrophication

Nitrates and phosphates in water can result in thea rapid growth of algae and other plants called, that

is eutrophication. A massive growth of aquatic plants can change the water significantly. Although

plants and algae add valuable oxygen to the water, overgrowth can potentially lead to reduced light

levels in the water body. As plants and algae die and decay, bacteria multiply and use the dissolved

oxygen in the water. The amount of available dissolved oxygen in the water may become very low and

harm fish and other aquatic animals. The resulting excess plant growth can cause taste and odour

problems in lakes used for drinking water or can cause nuisance and problems for users of the water

body. Water becomes murky, and the water temperature warmsrises. SThereforeo, excess nitrates

and phosphates can cause hypoxia (low levels of dissolved oxygen) and can become toxic to warm-

blooded animals at higher concentrations (10 mg/L or higher) under certain conditions. If the oxygen

level gets lowdrops, many types of fish and insects can no longer survive in the water.


Dissolved oxygen

Gaseous substances can also dissolve into water and. tThe amount of dissolved gas depends on

temperature and pressure. Dissolved oxygen analysis measures the amount of gaseous oxygen (O2)

dissolved in an aqueous solution. Only aA small amount of atmospheric oxygen is normally dissolved

in water. Dissolved oxygen is added to water through aeration (water running or splashing), diffusion,

and by photosynthesis of aquatic plants. Oxygen is important to all life. Aquatic life needs oxygen to

live and uses oxygen that is dissolved in the water even if is in much smaller quantities than in the air.

The maximum amount of dissolved oxygen in water (saturated solution) depends on elevation

(atmospheric pressure), water temperature, and salinity . Distilled water at 0° C has a O2 solubility of

14.6 mg/L at sea level. Dissolved oxygen in natural waters may vary from 0.0 mg/L to around 16.0

mg/L. Warm, still waters might have dissolved oxygen levels of about 4 or 5 mg/L. Cold, running

waters might have oxygen levels at 13 or 14 mg/L. Higher levels are possible due to photosynthesis by

(plants, algae), lower levels are possible due to oxygen consumption by respiration of biota (fish,

bacteria, etc).

Figure 10 : Oxygen dynamics in coastal waters (www. ozcoasts.org.au)

If more oxygen is consumed than is produced, dissolved oxygen levels decline. Dissolved oxygen

levels below 3 mg/L are stressful to most aquatic organisms. Some sensitive organisms will not live in

oxygen levels less than 7.5 mg/L. Dissolved oxygen levels that drop to low levels (i.e. below, less than

5 mg/L) are a reason for concern. The amount of dissolved oxygen in a water body also affects

whether a water body can provide optimal habitats for fish and other aquatic life. If compared to the

maximum allowed by the temperature of the water (saturation percentage), it tells more about the

measurements indicate a water body’s capacity of self-purification and/or a state of eutrophication .


Water and life

Water fills around 70% of the earth’s surface. , Additionally iit represents 60-90% of the content of cells

and of living tissue. Even minerals contain water in varying amounts. Water constitutes a fundamental

and irreplaceable resource for all organisms as well as playing a fundamental role in biological,

chemical, and geological cycles and in climatic balances. One can easily say that water is the key to

life on our planet. The first living organisms on earth are thought to have developed in primordial

oceans some 3.5 billion years ago, and their evolution was strongly influenced by the characteristics of

water, the element in which they were created. The chemical and physical qualities of water condition

all aspects of cellular structure and function and also most of the chemical reactions which occur

within a living organism. In order for these reactions to take place it is necessary that the molecules

within the cells arebe able to move around and meet with ease. This is possible in Aa fluid

environment enables this, and water is incredibly well suited for the purpose. A very important

characteristic of hydrogen bonds is their high “directional” structure, which is essential in the

organization of biochemical structures. For instance, they play a role in the are seen in spiralthree-

dimensional structures observed in proteins and DNA.

Moreover, because of water’s the intermolecular hydrogen bonds, waiter has a high specific heat (the

specific heat of a substance indicates the heat quantity necessary for anto increase of 1 C thein

temperature of 1°C of the unit of mass). Water also has and a high evaporation heat (necessary heat

neededto change to make a substance change from a liquid state to itsa gaseous form). This means

that a large amount of heat is necessary both to change the temperature and the physical state of

waterit (solid, liquid or gas). For this reason temperature changeshermal variations inside cells are

very lowsmall, even if the ambient temperature goes through strong changes. and thiThis, from a

biological point of view, has great importance as biochemical reactions happen withinin a small

intervanarrowl of temperature range.

Photosynthesis


As we have seen, water is not only one of the most important elements in the makeup offor all living

organisms are made of, but it also plays a basic role in biological processes: water is the liquid in

which all reactions of living organisms happen and it

very often placeys an active role in these reactions.

Lots of reactions, in fact, use or build water

molecules. Carbon dioxide and water are the final

products of oxidation of food substances like sugars

that gives the necessary energy for our survival.

Green plants use the sun’s energy to change water

and carbon dioxide into sugars (process of

photosynthesis) which are used as energy for the

plant’s metabolism or stored for later use.

Photosynthesis is possible thanks to the presence of

chlorophyll, a pigment that produces, as a by-

product, oxygen released into the atmosphere. Lots

of water plants do the same thing, giving oxygen to

water.

Figure 11: Pphotosynthesis (www. blogs.seattleweekly.com)

CHAPTER 4. MAN’S USE OF WATER (*)

(*) related to the HUMAN USAGE chapter of FYR Checklist

Worldwide, the largest use of water is for agricultural purposes (70%), followed by industrial activities,

(22%), and the smallest amount is used for domestic use purposes (8%).

The situation varies among continents, both in relation to consumption (e.g. per capita water

consumption is much lower in Africa than in Europe), and in relation withto sectors (e.g. in Europe and

North America the use in industrial sectors prevails, while in all the other continents water is mostly

used in agriculture).

Agricoulture (*)

(*) related to the HUMAN USAGE subchapter 1 - Agricoulture


Irrigation dates back to early times, and was already practised by the Babylonians, Egyptians, Incas

and Romans. In ancient times, agriculture flourished in great river alluvial plains, where plenty of water

was available. In the Nile delta, the periodic floods brought water and silt to the ground, and increased

the fertility of the soil.

The method of irrigation is based on distribution of water by flowing and infiltration in the soil by force

of gravity. Water from a river is diverted and distributed through a network of channels (questions 1 a-b-c).

Water consumption

Agriculture has not only developed in areas of the world, where regular precipitation make the soil very

fertile and moist, but also in dry regions where agriculture completely relies on irrigation from water

intakes such as rivers, lakes and underground aquifers. (questions d-e). The consumption of water

for irrigation depends on the kind of cultivation: for example, about 500.000 litres of water are required

to produce 1 ton of wheat, but even more than 4 millions litres are required to produce 1 ton of rice.

In agriculture a lot of water is often wasted because of obsolete canals, pipes and other inefficiencies,

but sustainable irrigation methods exist such as those which useing brackish water and purified urban

sewage. The method of drip irrigation is also more efficient than the classic method of canal irrigation:

water is distributed only where it is necessary.; tThis method helps to reduce consumption by 60%,

and improves production because crops receive water only at proper times and in appropriate

amounts.

Intensive agriculture requires lots of water.; iIt often degrades water quality and can also decrease the

quantity.; i In fact, deeper and deeper wells are dug to find water in dry areas and during drought

periods.

Water pollution

Furthermore, the risk of contamination ofng the surface and underground waters by agriculture is

extremely high (questions f). Polluting agents are mainly fertilizers and pesticides, which are spread

on farmlands to increase production and control unwanted insects, plants, and other animals

(questions h-i). Nitrogen, phosphorus and other compounds often found in these products, when not

absorbed, and disperse from farmlands into surface and underground waters when not absorbed,

producing such conditions as the afore mentioned eutrophication caused bybecause of thea high

concentration of nutrients (question g). Natural barriers, like riparian vegetation zones and wetlands

on the edges of the fields and along the riverbanks are often removed to increase production and help

mechanic means, but should in fact be restored and preserved because they are able to stop

nitrogenous and phosphor ousated chemicals from reaching waterbodies.


Industry

(*) related to the HUMAN USAGE subchapter 2 - Industry

Water consumption

Today water is used in many industrial processes: the washing of materials, the cooling of plants

(questions e) or the , dumping of wastes (questions c-d).

Industrial water consumption varies according to the kind of production (questions a-b), the level of

efficiency of plants, the production processes and the amount of recycling. Water, which is used in

production processes, can often be recycled: the percentage of recycled water in the paper and the

chemical industry is quite high, while this percentage in other production processes, this percentage is

almost zero.

Another negative side effect of industry is intake: oftentimes, industry diverts water to a degree that it

deprives rivers of their minimum flow requirements needed to ensure environmental functionality.

Water pollution

A large quantity of water is necessary to produce all the things we use in everyday life: cars, paper,

rice, oil, and cotton; these productive processes can create pollution problems related to both chemical

and biological by-products and to heat (questions e). The alteration of temperature is in fact very

dangerous for the life of the river ecosystems, because it damages the metabolism of flora and fauna

and alters the chemical balance of water. Pollution, arisinges from the dumping of industrial waste in

the rivers (questions c-d), (nitrogen and phosphorus from chemical industries and heavy metals from

mining, questions c-d). Every time water is diverted and returned to a river, it’s is inevitably altered.

However, if alternations are not too dramatic, they can be absorbed and neutralized by the river by

means of its natural capacity of self-purification. A well- functioning ecosystem is able to absorb

changes, if they are not too severe, and recover its balance quickly. The capacity of self- purification is

reduced or lost when a river has been stripped of its natural banks and consequently the necessary

level of biodiversity.

( to deepen the understanding of this topic see : WATER QUALITY chapter of FYR Checklist)


Civil use

(*) related to the HUMAN USAGE subchapter 5 : Water use

Pollution and potable water

The availability of clean water is fundamental for our basic needs such as drinking, cooking, and

washing.

The World Health Organization claims that five millions people die in the world every year because of

diseases related to scarcity of water or contaminated water.

Pollution from urban sewage, industries and agriculture, seriously endangers water resources.

Today, an increasing number of countries build sewage works for water coming fromleaving urban

areas (questions a-b-f) and impose limits and monitoring of industrial and production dumping, but

oftentimes, that is not enough.

In fact, the environment of a watercourse can only supply good water quality, if pollution remains

within limits and the majority of the elements of rivers, streams, wetlands, and flood areas have not

been altered (for example by building canals). This way, animals and plants communities can act as a

natural filter and purify waters. Healthy ecosystems are key to avoiding excessive water pollution, but

even in countries with plenty of water the majority of watercourses are actually subject to alterations or

unbearable pollution.

Water purification

Potable water for urban supply networks usually comes from underground aquifers, but its quality

strictly depends on the surface watercourses. In fact, water percolates through the soil or the river

beds, until it meets an impermeable clayey bed, where it accumulates, begins to flow and creates an

aquifer. If the surface water is polluted, it is almost sure that the aquifer below is polluted, too. While

soil acts as a filter, it is not able to stop all polluting substances from reaching groundwater.

Potable water is often the result of purifying water treatment, which are is designed to remove harmful

substances. Treatments vary from the separation of suspensions , to the removal of substances,

fromto the transformation of the biodegradable substances, and to the elimination of pathogens.

Various types of treatment are used to purify drinking water and depend on the incoming water quality

and the desired output (question c). Treatments can be mechanical, like filtration or sedimentation,

whichand have the objective to eliminate the solid parts, in their more or less rough form, that are

present in the water (sand, algae etc..);. cChemical treatments, such as chlorin ation and ozonization


and physical treatments as UV rays can be used to eliminate potentially harmful micro organism s .

Finally, biological treatments (questions b) such as septic tanks or a lagoon are used for waters from

urban as well asbut also industrial sources and rely on micro organisms, mainly bacteria, to

decompose polluting organic substances present in the water.

Water consumption

During the last century, private water consumption has increased 6 fold (source: UNEP, United

Nations Environment Programme). North America and Europe currently have by far the highest level

of per capita water consumption, but the request of water is increasing all over the world because of

development and production needs and, above all, for the demands of a higher quality of life

improvements.

An European citizen uses 130 liters of water daily on average. That is on the order ofabout 10 times

the amount available to each person in developing countries, which is used tfor drinking, cooking and

washing (question a). In industrial countries, water supply and sewag e is usually ensured by a

widespread system of waterworks and sewers. Yet, this system does not exist in developing countries,

where a part of the population does not yet even have clean water or there is a lack of sewerage

systems. Furthermore, if a supply system even does exists, it is often inefficient: up to 60% of water

disperses through broken pipes or is illegally diverted.

Water is fundamental for human life and for the health of natural ecosystems.; tTherefore, the choice

of strategies to avoid waste is necessary both in countries abounding with and lacking water.

Maintenance of the efficiency of water supply systems, installation of facilities for water conservation,

water treating and recycling, discouragement of wasteful practices (for example, controlling

consumption through counters and adopting pricing policies, which considers the actual price of water)

(question d), and promotion of fair use of water through information campaigns, is therefore the duty

of every community.

How much water is necessary…

§ to have a bath: between 120 and 160 litres

§ to have a shower of 5 minutes: between 75 and 90 litres

§ to flush of toilet: up to 16 litres

§ to wash hands: 1,4 litres

§ to brush teeth leaving the tap running: up to 15-20 litres

§ to brush teeth turning off the tap: 2 litres

§ to drink and cook: about 6 litres daily per person


§ to do the dishes by hand filling the bowl of the sink: 20 litres

§ to wash a full load in the dishwasher: 40 litres

§ to wash a full load in the washing machine: 80-120 litres

§ to wash the car using a hose: 800 literes

§ to air-condition an eight-story building: 3,000,000 litrers daily

Domestic saving

We have already seen that a lot of water is wasted by the supply system network, but citizens often

use water without care, too. A very small amount of drinkable water is used daily for drinking and

cooking, while a large amount is used for flushing toilets, washbasins, washing machines,

dishwashers, and baths. There are many opportunities to improve the future of water use. Small and

careful everyday actions practices empower people to meditate on environmental problems and adopt

fair behaviours towards a precious resource for the whole of human kind.

The following behaviours are examples of what we can do:

- Do not let the tap run, but turn it on only when necessary.

- Repair any leaks at home. A dripping tap can waste up to 4,000 litres of water a year.

- Plunge vegetables into water instead of washing them under running water: this way each

family can save up to 5,000 litres a year.

- Wash only full loads in the dishwasher and the washing machine; remember to use the

economy or energy saving program.

- Reduce the waste of potable water with each flush. For example, use a variable flush, which

n this way c,000 litres a year can be saved

- Apply a low-flow faucet aerator to your faucets/taps to reduce water flow.

- Take a shower rather than a bath.

- Water indoor plants in the morning or at dawn and, if possible, recycle the water from washing

vegetables.

- If possible, do not use potable water to wash the car.

Rivers: not only water (*)

Rivers as lines of communication (*)

(*) related to the HUMAN USAGE – subchapter 7: historical aspects



Amount missing

Rivers also are important lines of communication and, especially rivers with wide beds, slight slopes

and regular flows. Navigable channels often link rivers and locks are sometimes used to move across

uneven water levels. Waterways are mainly used to transport goods, passengers and for tourism.

In Europe, many channels and rivers are navigable, such as the Rhine and the Danube. Huge

hydraulic works sometimes maintain the navigability of rivers, but deeply change the natural structure.

For example, the depth of a river bed must be kept at a minimum level all over the year long for trade

activities; for this purpose, channels and excavations are made (question 3 g).

Since ancient times, rivers have indicated great routes across the Earth. The proximity of rivers

encouraged the settlement of peopleulations and the their activities growth of their activities for

centuries. Road systems were and are based on their courses, which are modes for communication

and transport. A river is at the centre of all activity within its boundaries: to supply irrigation channels

with water, to run watermills - therefore to serve as an energy source - to supply cities with water.

Many cities were born as small villages on a river bank or on an island on the river (7:question b-c). (fFor example, Paris was founded by Celts on the Ile de la Cité in the middle of the river Seine more

than 2000 years ago). When the city expanded, it occupied both river banks and the river remained in

the centre. Bridges, fixed structures to cross the river, were built to connect the two parts of the city.

Based on the available materials, the historical age and the characteristics of the river, wood, stone,

concrete and steel bridges were built with using different structures, but with the same function.

Several towns, such like Florence in Italy, have bridges that sometimes are inhabited, too (Ponte

Vecchio) (questions subchapter 6: tourism and subchapter 4: urbanization).

Rivers were elements of union as well as of division among people and nations. Since it was difficult to

cross rivers, they were in fact effective means of defensedefence. They were embanked, canalised,

lead into ditches, and became political and military borders, rather than elements of unification of

territories.

Culture and recreation

(*) related to the HUMAN USAGE – subchapter 6: tourism and 4: urbanisation


A river is a protagonist in human culture: in history, literature, architecture and art. The river is

reproduced in pictures and writings because of its beauty and its meaning to man: spiritual, domestic,

adventureous, unknown, etc. ...Since very ancient times, people exploited rivers by necessity as well

as for recreation and adventure (this is illustratedshowed by evidences dating back to the Assyro–

Babylonian and Egyptian civilizations). Today, rivers are tourist destinations and places to practice

various sports (rafting, kayaking, canoeing, mountain bikingg, sailing, rowing, etc.…) ) (question 6 a-b-c). For tourism and recreation pursuit, remote and wild places are often reached, which are often the

last ”natural refuges” for animals and plants. In order to protect these places, it is extremely important

to adopt sustainable practices for these environments.

Today, environmental degradation, pollution and destruction of rivers and watersheds (question 4 a-b-c-d) symbolize the breaking up of the complex balance among land, water and life, which formed

the basis for almost all civilizations. Land was very often exploited to produce wealth, without

consideration of the ecological, as well as human and collective value of the wild environment, which

gives man shelter and livelihood.

BIBLIOGRAFY- Various authors. Viaggio sul fiume. Edizioni Carthusia. Milano, 1992

- Various authors. Classi Controcorrente. Quaderno di Educazione Ambientale WWF n. 41, 2001

- Various authors. La terra fa acqua da tutte le parti…©. Quaderni di Educazione Ambientale WWF

n. 47. Edizioni Carthusia. Milano, 2002

- Andrea Agapito Ludovici. Salviamo i fiumi. WWF Lombardia, 1997

- Andrea Agapito Ludovici et al. Tutela, gestione e rinaturalizzazione dei fiumi. WWF Lombardia,

1996

- Centro Italiano di Riqualificazione Fluviale. Manuale di riqualificazione fluviale. CIRF, 2001

- M. Cremaschi e Rodolfi. Il suolo. La Nuova Italia Scientifica. Roma, 1991

- Edigeo. Enciclopedia Zanichelli. Dizionario enciclopedico di arti, scienze, tecniche, lettere, filosofia, storia, geografia, diritto, economia. Zanichelli. Bologna, 1992

- M. Olivieri. Come leggere il territorio. La Nuova Italia, Firenze, 1978

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Cremona, 1995

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dell’Ambiente, II Edizione, 2003

- P. Petrella. Il Manifesto dell’Acqua. Edizioni Gruppo Abele, 2001

- OCSE. Esame Ocse sulle performance ambientali. 2002

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sostenibile. 2001


- Andrea Agapito Ludovici. Il governo dell’acqua in Italia: rilancio o crisi? WWF Italia, 2005

- Allan. Stream ecology: structure and function of running waters. Chapman & Hall. London, 1995

- G. Sansoni. Atlante per il riconoscimento dei macroinvertebrati dei corsi d’acqua italiani. Provincia

Autonoma di Trento, 1992

- Gerard Lacroix. Laghi e fiumi, mondi viventi. Garzanti, Milano, 1991

- Accademia Nazionale di Agricoltura. Agricoltura e ambiente. Edagricole. Bologna, 1991

- Steve Parker. Fiumi e stagni. De Agostani. Novara, 1998

- IUCN-UNEP-WWF. Caring for the Earth. A strategy for sustainable living. 1991

- IGBP. Global Change and the Earth System: a Planet under stress. IGBP Science n.4, 2001

- UNEP. Global Environment Outlook 3. Earthscan, 2002

- OMS. Our planet, our healt. 1992

Index of figures

Figure 1: EU Water framework Directive campaign (Italian version)........................................6

Figure 2: How wetlands work (www. beachwoodhistoricalalliance.files.wordpress.com).........8

Figure 3: A watershed...............................................................................................................9

Figure 4: River morphology.....................................................................................................14

Figure 5:..................................................................................................................................21

The hydrological cycle............................................................................................................21

Figure 6: Structure of hydrogen bonds...................................................................................23

Figure 7: Polarity of water molecule.......................................................................................23

Figure 8: Solid form of a salt (www.bbc.co.uk/.../ionicrev3.shtml )........................................25

Figure 9: Process of dissolving..............................................................................................25

Figure 10: Oxygen dynamics in coastal waters......................................................................27

Figure 11: Photosynthesis......................................................................................................28

(www. blogs.seattleweekly.com).............................................................................................28


Jegger II, 16/03/10,

Don’t know why fig 5 and 11 won’t go into one line…

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