The role of four key structures in the creation and survival of cultural landscapes in the desert

15 Pages·2014·0.64 MB·English

by  Maryam Rafiee Fanood

Journal of Architectural Conservation
The role of four key structures in
the creation and survival of cultural
landscapes in the desert environment
of Iran
Maryam Rafiee Fanooda
a Faculté des Sciences Humaines et Sociales, Université Jean
Monnet, Saint-Etienne, France
Published online: 06 Dec 2014.
To cite this article: Maryam Rafiee Fanood (2014) The role of four key structures in the creation
and survival of cultural landscapes in the desert environment of Iran, Journal of Architectural
Conservation, 20:3, 184-196

JournalofArchitecturalConservation,2014
Vol.20,No.3,184–196,http://dx.doi.org/10.1080/13556207.2014.985490
The role of four key structures in the creation and survival of cultural
landscapes in the desert environment of Iran
Maryam RafieeFanood*
FacultédesSciencesHumainesetSociales,UniversitéJeanMonnet,Saint-Etienne,France
Cultural landscapes in the desert environment of Iran were created according to specific
climatic conditions and differ from those in other climates. Scarcity of water resources in
these regions has led to the invention and application of unique measures for the supply,
maintenance and use of water. The qanat, cistern, ice-house and wind catcher are ingenious
measures that have had key roles in the settlement of man in desert regions of Iran and
ideallyaddressedthespecificneedsofeachcommunityovercenturies.Thisstudyillustrates
the significance and relationship of these elements in the creation and survival of cultural
landscapes in the desert environment of Iran. To this end, their features are discussed and
analyze separately and as ensembles which in turn presents a sustainable way of living in
desertregions.
Keywords:culturallandscape;desertenvironment;qanat;cistern;ice-house;windcatcher
Introduction
Culturallandscapesrepresentthecombinedworksofnatureandofman.Theyareillustrativeof
theevolutionofhumansocietyandsettlementovertime,undertheinfluenceofthephysicalcon-
straints and/or opportunities presented by their natural environment and of successive social,
economic and cultural forces, both external and internal.1 With this UNESCO definition in
mind,inthecentralplateauofIranwheredesertispredominant,thereisahugewealthofcultural
landscapes. The scale, dimensions and forms of cultural landscapes vary immensely, and may
range from quite small, contained landscapes (such as a small saffron farm in South Khorasan
Province)tovast,extensiveareas(suchasthehistoriccityofYazd).Smallerculturallandscapes
may themselves form part of more extensive cultural landscape areas. However, these rich and
varied landscapes seem to be in permanent or potential danger that might cause irreversible
deterioration or even disappearance if urgent measures are not taken by the decision-making
sectors. They are being threatened by uncontrolled urban and rural development, insufficient
knowledgeofinhabitantsandstakeholdersaboutmanagementtechniquesandlackofawareness
oftheirsignificanceaspartofasustainablewayoflivingformanycommunitiesandasanattrac-
tion for culture, tourism andscience.
Themeaningandsignificanceofculturallandscapesislargelyderivedfromtherelationship
betweenthelandscapeandtheelementswithinthatlandscape,aswellastherelationshipbetween
theindividual elements themselves. Thus landscape meaning and significance canbe lost when
important components of a cultural landscape are removed or evidence relating the feature to
*Email:Maryrafi[email protected]
©2014Taylor&Francis
Journal of Architectural Conservation 185
thelandscapesettingvanishes.2Thispaperexplorestheroleofsomeofthesekeyelementsinthe
creation and survival of cultural landscapes in the desert environment of Iran through history.
Although each cultural landscape encompasses a great variety of elements and components
that differ one from another, this study particularly focuses on four common structures which
have been used for the supply, maintenance and use of water in the arid environment of Iran.
The most important and the most basic key structure is the qanat, a sustainable water supply
system,which,inconjunctionwithotherstructuressuchascisterns,ice-housesandwindcatchers,
has provided comfortable living conditions for desert environment inhabitants.
Climate conditions of thedesert environmentof Iran
AdesertenvironmentcoversthecentralandeasternpartsofIran.Overall,itsclimaticconditionis
characterised by:
. Limited waterresources;
. Warm anddry summers, cold and hard winters;
. Lowrainfall;
. Lowhumidity;
. Scant vegetation;
. Largevariation between day andnight temperatures; and
. Dusty winds and sandstorms.3
InthecaseofYazdcity,oneofthedriestcitiesinthecenterof Iran,theaverageannualrainfallis
60mm.Thesummertemperaturesareveryfrequentlyabove40°C,withblazingsunshineandno
humidity;evenatnightthetemperaturesareratheruncomfortable.Inthewinter,thedaysremain
mildandsunny,butthenightshaveverycoldtemperaturesthatcanfallbelow0°C.Theseasonal
temperaturesvarywidely;rangingbetween+45°Cinsummerto−20°Cinwinter,furthermorethe
temperature difference between the daytime and night-time is also high and can range from an
average of 11.9°C to 20.7°C.4 Several features of the traditional structures are designed to take
advantage of thiswide temperature range in desert regions.
Four key structuresof cultural landscapes in the desert environment
Qanat
Water is not only vital for human existence, but also of substantial importance in any food
production process as well as essential for environmental sustainability. Three thousand
years ago, Iranian people, with their knowledge of underground water resources, understand-
ingofgravityanduseofaseeminglysimpletechniqueofdiggingwellsandtunnels,wereable
to overcome the water shortage in arid and semi-arid regions.5 They developed indigenous
methods for harvesting and Extracting their scarce groundwater in a sustainable manner in
an area where there have been no other water resources. This technique, which is called
qanat, has maintained its significance and function in the survival of many communities in
the country until the present.
Themaingoalsofconstructingqanatshavebeentoprovidehygienicdrinkingwaterandirri-
gation for agriculture; however, there have been secondary purposes, which allowed the popu-
lation to live comfortably in a desert environment. To fulfill these purposes the qanat has
operated in conjunction with other structures such as cisterns for water storage, ice-houses for
ice storage, wind catchers for air conditioning,andwatermills forgrindinggrains.6
186 M.R. Fanood
Qanatsexpressalongandintimaterelationshipbetweenpeopleandtheirnaturalenvironment,
andwithoutthemthousandsofvillagesandtownswouldnothavecomeintoexistence.Bamand
its cultural landscape, which was placed on the World Heritage List in 2004, is an outstanding
example of the interaction of man and nature in a desert environment by using the qanats; the
existence of life in the oasis was based on these underground irrigation canals.7 The irrigation
system of the majority of the Persian Gardens, placed on the World Heritage List in 2011, has
alsobeen based on the qanat system. Qanats have been maintained in all, except Bagh-e Eram,
Bagh-e ChehelSotun and Bagh-e Dolat Abad, where urban development has forced the closure
of qanat sources and replaced them with wells.8 However, it is evident that most of these
unique gardens would not have been created and survived over centuries without qanats, as
there have been noother water resources for irrigation in those regions.
Qanats are generally constructed on the slopes of piedmont alluvial fans, in intermontane
basins, and along alluvial valleys. In these locations, this groundwater collection system has
longbroughtwatertothesurfaceandsupportedsettlementinregionswherenoothertraditional
watertechnologywouldwork.9Qanatsconsistofseriesofwell-likeshaftsconnectedbyagently
slopingtunnel. The main components of the qanatas presented in Figure 1 are:
. Mazhar or aquifer where the water flows above the ground ator nearsettlement site;
. Gallery,whichisanalmosthorizontaltunneldugtogetaccesstothegroundwaterreserve
andto transfer it to the earth surface;
. Wetsection,whichisinfact anundergrounddrain intowhichgroundwaterseeps.Thisis
the water producingsection of the qanat; and
. Drysection,whichisthedown-slopesection,merelyactingasthetransportationsectionof
the qanat;
Figure1. Cross-sectionandmainfeaturesofatypicalqanat.
Journal of Architectural Conservation 187
. Shafts,whicharewellssituatedalongthegalleryinordertofacilitatesoilextractionaswell
as ventilation anddredging;and
. Mother well,which marks the furthest extent of the qanat from the aquifer.10
Cultivated land and settlement sites are situated downwards from thepoint where the water
surfaces.Theimmediateoutlet,mazhar,isthepointwherepeopletakewateranditisgenerally
locatedinthemainsquareofavillage.TheMazharisanimportantfeature,whichiswellmain-
tainedandmortaredtopreventwaterpenetrationintothesoil.11Downstreamofthemazhar,water
runs through open or covered ditches with lateral branches to the neighbourhood, gardens and
fields. Cisterns, ice-houses, Hammams or public baths, mosques and watermills were built
along the route of the water canals in the most suitable locations.12 Payabs, which are sloping
corridors with steps leading from the surface to the qanat’s canal beneath residential areas,
were also built along the line of the qanat for taking drinking water directly from the qanat.13
After these communal needs have been met, the water is collected from ditches in special
pools and then distributed to the farms.
Whatisremarkableabouttheqanatisitstraditionalwatermanagementanddivisionsystem,
which has provided maximum efficiency, fair distribution and suitable maintenance of water in
arid regions of Iran. Water distribution for irrigation is done proportionately according to the
land shares of farmers so that each one receives his just share of the water at the proper
time.14 Different methods have been used for measuring the water share, which vary from area
to area according to the local conditions and the volume of the water available. The most
commonmeasureinthedesertregionsofIranhasbeenbasedontime,whichledtotheinvention
of aspecial water clockto calculate the lengthof irrigation for each farm.15
QanatshavebeeninwideuseassustainablewatersuppliesthroughoutthearidlandsofIran
until today for several reasons: they are made of local materials and are resistant to natural
disasters and deliberate destruction in war; they use no source of power other than gravity; and
water is transported for substantial distances with minimal loss through evaporation and with
littlerisk of pollution.16
Cistern
Thecistern,orĀbanbār,isatraditionalreservoirfordrinkingwaterthatwasusuallybuiltatthe
centreofthecityorvillage,oncaravanroutesandinsideprivatedwellings.Thecisternwasoneof
the constructions developed in arid regions of Iran as part of a water management system to
ensuretheavailabilityofdrinkingwaterthroughoutthehot,dryseasonswheneventhepermanent
water supply,the qanat, would diminish.
TheearliestcisternsarebelievedtohavebeenconstructedalongsidetheriseofearlyPersian
civilizations.ThewaterreservoirofTchoghaZanbil,anElamitecityintheKhuzestanprovince,
stillsurvivesfromthesecondmillenniumBC.Therearealsoremnantsofcisternsandwaterways
atPersepolis,thecapitaloftheAchaemenidEmpirefromthesixthcenturyBC.17However,most
extantcisternscantodaybetracedtothelateSafavidandQajardynasties(eighteenthtotwentieth
centuries).
Theprimeobjectiveinconstructingacisternwastoprovideatotallywaterproofcontainerfor
alargevolumeofwaterwhileallowingproperventilationandaccess.Thetypicalcisterngener-
ally consists of three key elements: the water reservoir, which was built undergroundlevel to
enablepropercooling,resistancetowaterpressureandimpactsofearthquakes;thepassageway
to a platform where a faucet is used to take water; and the wind catcher, which is used for
ventilation (Figure 2).18 Two types of structures have been noted: first, a cylindrical reservoir
188 M.R. Fanood
Figure2. Cross-sectionofapubliccistern.
with a dome, which was generally built for public cisterns in towns or along caravan routes
(Figure 3). Their capacity generally varies from 300 to 3000 cu m depending on their depth
and diameter. Second, a rectangular reservoir with flat roof supported by piers or pillars, which
was often built into the foundation of private houses for domestic use and ventilation. Each of
thesestructureswasmarkedbyaportalthatopenedintoastaircasedescendingtoavaultedpas-
sageway,leading downto the reservoir.19
Cisternsweremadefromspecialbricksandwaterproofmortarcalledsārūj,whichisthought
toberesistanttowaterpenetration.Waterwasmainlybroughttothecisternbyspecialchannels
leading from the main qanat or, alternatively, where no qanats were available the water was
collectedfromsporadictorrentialrainfallintheariddesertareaoftheIranianplateau.Thecisterns
werefilledduringthewinterwithcoldwateratatemperaturejustabovefreezingtokeepthewater
cool throughout the year.20 Water remained quite cool inside the cistern, since it was generally
Figure3. ApubliccisterninArdestan,IsfahanProvince,2012.
Journal of Architectural Conservation 189
built beneath ground level and was insulated with very thick walls.21 Domed roofs, which are
used to cover cisterns, have a good thermal performance. Some of them had an escape vent in
the centre, which enabled them to cool water by air convection while protecting it from dust
andotherpollution(Figure4a).Somecisterns,mostparticularlyinYazdprovince,wereequipped
withoneormorewindcatchers.Thepressuredifferencebetweentheairenteringfromthewind
towersandtheairleavingfromthetopofthedomecausedanaturalairflowoverthewatersurface
(Figure4b).Thisprocess,whichisdescribedinthefollowingsection,resultedintheevaporation
and subsequent cooling of water.22
Wind catcher
Thewindcatcher,orBādgir,isatraditionalventilatingdevicethathasprovidednaturalaircon-
ditioninginthebuildingsofhotandaridregionsofIranforcenturies.Themostcommonuseof
windcatchersistocoolandventilatetwointeriorspacesatdifferentlevels:thebasementandthe
summerlivingroomonthegroundfloor.Theywerealsobuiltontothelivingquartersofcaravan-
serais, over prayer halls of mosques, and above the cisterns as mentioned above.
Awindcatchergenerallyconsistsofawindtower,whichisachimney-likestructurewithone
endinthebasementofthebuildingandtheotherendpositioningabovetheroof.Thewindtower
isdividedintoverticalairpassageswithventsatthetopinoneormoresidesofthetower’sheadto
catchtheprevailingwind(Figure5).23 Airtrappedintheventsofthetoweriscooledasitfirst
passesoverawaterreservoirorsmallpondinthebasement;alternatively,orinaddition,insome
places mats were often placed across the vents over which water might be thrown on summer
afternoons.24 The qanat’s canal, which passes beneath the basement, has also been used to
increase the humidity and the coolness of the airflow. The flow of the incoming air from the
wind catcher is directed across the vertical shaft opening of the qanat to the basement that
creates a lower pressure and draws cool air up from the qanat tunnel (Figure 6). In dry desert
climates this can result in agreater than 15°C reduction in the air temperature coming from the
qanat.25Somewindcatchers,asshowninFigure7,werebuiltawayfromthebuildingandcon-
nectedtoitwithanundergroundductthatcouldserveseveralbuildings.Thehotaircooledeither
by contact with the duct’swall thatwas damp dueto thewatering ofthegarden above it,or by
passingoverapondinsidethebuilding.26Asaresult,thiscoolhumidairisabletocooltheother
spacesinthebuilding byconvectionandevaporation.Theflowofairthroughdifferentpartsof
buildingcan becontrolled by opening and closing the tower and building doors.
Figure 4. Air circulation in a cistern (a) with vents on a domed roof; (b) with wind catchers (Bahadori
1978).
190 M.R. Fanood
Figure5. ThewindtowerofGanjali-Khanbazaar,Kerman,2008.
Awindtoweroperatesinvariouswaysduringdayandnightaccordingtofluctuationsinthe
air temperature, the intensity of solar radiation, the wind velocity and other climatic variables.
When there is little or no wind, the wind catcher operates according to temperature differences
between day and night. The wind tower operates like a chimney when there is no wind at
night. Heat that has been stored in walls during the day warms the cool night air in the tower.
Thiscausesalowerpressureatthetopofthetower,whichdrawsupthewarmairinthebuilding.
Coolnightairispulledintothebuildingthroughtheopendoorsandwindows.Whenthereisno
wind during the day, the operation of the tower is the reverse of a chimney. Hot ambient air is
cooledwhenitcomesintocontactwiththetowers’walls,whichhavebeencooledduringthepre-
viousnight.Thecooleddenserairsinksdownthroughthetowerandcirculatesinthebuilding.27
Windcatchersindesertregionsarebuilteitherofmudbrickormorecommonlyofbakedbrick
coveredwithmudplaster.Thesematerialsexhibitgoodresistanceagainstheattransmissionqual-
ities, ensuring that the wind catcher operates effectively as a cooling system.28 To fulfill this
purpose the orientation and height of the wind tower are also important. They may have vents
at the top in one, two, or up to eight sides depending on the direction of the desired airflow at
that specific location. In hot and dry regions, due to the low temperature and a higher wind
velocity at greater heights, wind towers are built at high levels to enable them to trap such cur-
rents. The highest wind tower in Iran built at Bagh-e Dolat Abad in Yazd city has vents in
eight sides and rises about 34m abovethe roof of the garden pavilion itserves.29
Ice-house
Ice-houses,orYakhchāls,arestructuresusedtoproduce,storeandpreserveicethroughoutthehot,
aridregionsofIran.Icewasproducedinthecoldestperiodsofwinterandpeoplewouldusethe
preservediceduringthelongandwarmsummers.Mostoftheice-houseswereapublicutilityand
everyone could use the ice for conserving food, cooling drinks, and preparing ice-cream and
Journal of Architectural Conservation 191
Figure6. Coolingsystemofawindcatcheralongwithaqanat(Bahadori1978).
sorbetdesserts.30Althoughseveralhistoricalice-housesremain,nonecanbedatedtobeforethe
Safavid dynasty (1501–1722). However, historical sources attest to the extensive use of ice for
conservingfoodandcoolingdrinks,indicatingthatitwasalongestablishedpracticeinPersia.31
A typical ice-house consists of three main components: an ice-making pool, a great shade
wall, and an ice reservoir (Figure 8a). The ice-making pools were long, rectangular, shallow
pits, 100by10m with a depth of about 40to50cm, linedwith baked bricks that rendered them
waterproof.Alongthesouthsideofthepoolwasatalltaperingwall,upto10mhighandstretch-
ingfromeasttowestinordertoprovideshadefromthesunduringtheday,andthusaccelerating
thefreezingprocessatnight.Thewallfurtherprotectedthepitsfromwind,whichcanalsohinder
thefreezing process.32
Although snowfrom nearbymountains wasoccasionallystoredin ice-houses,mostice was
madebyfreezingwaterinnearbyshallowpitsthatwerefilledwithwaterfromtheqanats.33The
procedure is based on the high discrepancy of temperature between day and night in both
summer and winter. Water froze in the pool when the temperature dropped to freezing during
winternights.Inthemorning,beforesunrise,theicewasbrokenandstackedintheicereservoir
where it was insulated with straw or saw dust andkept dry.34
Icereservoirsindesertregionsweremadebyconstructingabigadobedomeabovealargepit
to the south of the shade wall. The dimensions of the ice reservoir were different. One of the
biggest examples of an ice-house is in Meybod city, Yazd province, with a pit depth of 6m
and a dome height of 13m (Figure 8b). The depth of the pit under the ground stabilises the