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IRRIGATION METHODS AND IRRIGATION SCHEDULING

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IRRIGATION METHODS AND IRRIGATION SCHEDULING Powered By Docstoc
					On overview on WUE & WP
   in Italian agriculture

                                   by

                 M. TODOROVIC
                CIHEAM-IAMB, Italy
                  A. CALIANDRO
                  University of Bari,
         Faculty of Agriculture Italy
                     R. ALBRIZIO
                CIHEAM-IAMB, Italy
                                                     Bari




Main climatic zones
according to the Köppen
climatic classification

                      Source: www.italocorotondo.it/tequila/partner_section/italy_english/
        Temperature
Minimum    and     Maximum




       Bari                              Bari




                       Source: UCEA, Rome, 1995)
Sunshine hours      and   precipitation




             Bari                                  Bari




                                  Source: UCEA, Rome, 1995)
Water resources availability synthesis

Average precipitation [mm/year]                                                       982
Flow generated by average precipitation [km3/year]                                    296
Average evaporation [mm/year]                                                     428 (438*)
Evaporation losses [km3/year]                                                     129 (132*)
Subsurface flow to the sea [km3/year]                                               12 (9*)
Internal renewable water resources [km3/year]                                 155 (=296-129-12)
External runoff – inflow from other countries [km3/year]                              7.6
Total groundwater availability [km3/year]                                              40
Groundwater recharge of local aquifers [km3/year]                                   10 to12
Spring outflow from local aquifers [km3/year]                                         3.5
Total renewable water resources [km3/year]                                  166.1 (=155+7.6+3.5)
Potentially usable water resources [km3/year]                                         110
* there   are some difference between data coming from different sources


                             Source: ANPA, 2001; IRSA CNR, 1999; EUOSTAT, 1998; AQUASTAT, 1998, Blue Plan, 2001
     Regional distribution of potentially usable
     water resources in Italy
                         Islands
                           4.5%
            South
            18.2%                  North
                                   59.1%




                                                                    In m3/person/year …
        Center                        3000
        18.2%                                  2542
                                      2500

                                                       1834                       1930
                                      2000
In percentage …
                                                                1451
                                      1500

                                      1000
                                                                         743
                                      500

                                           0
                                               North   Center   South   Islands   Italy

Source: IRSA CNR, 1999
Average water withdrawal
by sectors in Italy


                   domestic
                     15%




        industry
          25%                 agriculture
                                 60%
Sectorial water use in Italy for
a hydrologically normal (1991) and a dry (1999) year



  Sectors of water                   1991 (a normal year)                          1999 (a dry year)
  use
                             Water use [km3]        Water use [%]           Water use [km3] Water use [%]
  Domestic                            8                   16.0                   7.9               19.6
  Industry                            12                  24.0                   8.0               19.7
  Energy*                              -                     -                   4.5               11.1
  Agriculture                         30                  60.0                   20.1              49.6
  Total                               50                  100.0                  40.6             100.0
 * Includes   only the use of freshwater for thermoelectric plant cooling




                                                                     Source: ISTAT, 1991; IRSA CNR, 1999; MPAF 2004
Land use in Italy and EU countries


                                                                        Other EU       Central EU
                                                                                                         Total
                                                                      Mediterranean    countries            (***)
                                                          Italy                             (**)         EU
                                                                       countries (*)
              (1)
  Arable land
                   (2)
                                                           37     +        33               32             27
  Permanent crops                                          29     +        26               32             37
  Moorland (areas over 20% covered by shrubs)              8      -        20                4              8
  Permanent meadows and pastures                           10              11               20             12
  Bare ground                                              6                5                3              3
                                 (3)
  Inland waterways and wetlands                            3                1                3              8
                                     (4)
  Unproductive areas and other land                        7      +         4                6              5
  TOTAL AREA (000 ha)                                    30,133          72,988          110,172     292,105
  (*) Greece, Spain, Portugal.
  (**) France, Germany, Belgium, Luxemburg, Denmark, The Netherlands,
  (***) Excluding UK and Ireland,
  (1) Including temporary forage crops and set aside.
  (2) Tree and other permanent crops (woods and forests).
  (3) Including glaciers and eternal snow.
  (4) Man-made and industrial settlements, infrastructure, rocks and barren land; ornamental parks and

  gardens, roads, railways, etc.



                                                                         Source: INEA, 2003, on EUROSTAT survey
                          Irrigable and irrigated land
Region                    Irrigable land [ha]   Irrigated land [ha]   Irrigated/Irrigable [%]
Piemonte                       448,947               335,800                  79.25
Valle d’Aosta                   26,212                23,623                  90.12
Lombardia                      700,140               554,382                  79.18
Liguria                         11,244                 7,191                  63.96
Trentino – Alto Adige           61,774                57,768                  93.51
Veneto                         435,845               265,253                  60.86
Frulli – Venezia Giulia         91,876                63,202                  68.79
Emilia Romagna                 565,573               252,377                  44.62
Toscana                        111,603                47,286                  42.37
Umbria                          66,927                32,117                  47.99
Marche                          49,470                25,070                  50.68
Lazio                          150,088                74,052                  49.34
Abruzzo                         59,358                29,995                  50.53
Molise                          20,881                11,812                  56.57
Campania                       125,305                86,414                  68.96
Puglia                         389,617               248,814                  63.86
Basilicata                      80,640                42,325                  52.49
Calabria                       117,143                66,922                  57.13
Sicilia                        209,036               161,044                  77.04
Sardegna                       165,709                62,315                  37.60
                                                                                                Source:
ITALY                     3,887,387             2,467,763                    63.48              ISTAT, 2002
Irrigated crops in Italy in ha and
as % of total cultivated area of each crop
                    85.8 113,600 ha
       90
                                                                        217,000 ha
       80                                                                  70.0
                                                                                        67.4
       70
                                                    622,000 ha 58.2
       60
                           81,000 ha          189,000 ha
       50
                           36.2                      38.0
       40                                                                                      34.5
                                                                                                             183,000 ha
                                  267,000 ha                                                          25.5
       30
                                  17.5
       20                                                                                                    10.0
                                                             6.7
       10                                    4.5

           0




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                                                                                                                    Source: ISTAT, 2002
Irrigation methods in Italy

                                202,000 ha
                                      basin other methods 2,300 ha
                           micro-     8.2%      0.1%
            75,318 ha    irrigation
                            3.1%

                     drip                                       1,047,000 ha
                    11.8%                                       sprinkler
          290,700 ha                                             42.4%




                            furrow
               surface and furrow
                            34.5%
                                      850,480 ha




                                                                               Source: ISTAT, 2002
The most utilized irrigation methods
in some Italian regions
Group for Irrigation Studies
Gruppo di Studio sull’irrigazione - GRU.S.I.

 Constituted in 1962-63 and promoted by the Italian National
  Research Council
 Main research themes:

Biomass
 & Yield         Crop yield response to irrigation water
                 Crop water requirements
                 Biomass and Yield WUE (WP)
                 Water saving practices, deficit irrigation etc.




                                                          (E)Tc
Studies
on



Crop yield response
to irrigation water
Trend of some herbaceous crops production


           Yield
           (% of the
           maximum)




Based on data                                ETc (%)
from Policoro,
Southern Italy




                                Source: Venezian Scarascia et al., 1987
Mitscherlich model modified by Giardini and Borin


                    
           y  y m 1  10    c b  d 
                                            10    k b  d 
                                                               2

                                                                    1  10
                                                                           1c b d 
                                                                                         
  y = crop production
  ym = max obtainable crop production under non-limited water supply
  c = coefficient of increase, indicating the rapidity of achievement of
   the maximum production
  k = coefficient of depression, indicating the tendency of y to
   decrease after achievement of the maximum value
  b = quantity of water available for the crop in natural conditions
  d = quantity of water applied under specific experimental conditions
Parameters of the Mitscherich equation,
flex point coordinates and
seasonal irrigation volumes at 100% of yield

                                                                                      Seasonal
                         Equation-parameters           Flex point coordinates
                                                                                      irrigation
                                                                                   volume at 100%
                       Ym         b         c         Water volume      Yield
                                                                                       of yield
                    (% of the (% of the   (ha /      % of      3       (% of the         3
                                                -3           m /ha                    (m /ha)
                    max yield)  ETc)    %ETc10 )    ETc                 max)

Tomato                 78.5      13.9       23.0     29.6     1435      35.3           4734
Pepper                 84.9      15.1       20.1     34.6     2004      38.2           5800
Spring maize           91.0      15.4       27.6     20.8      994      41.0           4181
Summer maize           94.9      10.0       16.4     51.0     1603      42.7           3085
Egg-plant              82.9      23.1       30.4      9.8      441      37.3           4795
Shell-bean             96.9       2.2       15.8     61.1     1898      43.6           3109
Dry-bean              102.0       4.9       14.9     62.1     2121      45.9           3413
Spring sugar beet      75.9      39.1       32.7     -8.6          -    34.2           7193
Autum. sugar beet      82.0      49.4       23.1     -6.2          -    36.9           4961
                                                                                   Based on data
                                                                                   from Policoro,
                                                                                   Southern Italy
Production of some herbaceous crops as a function of
seasonal water volumes expressed as % of estimated ETc
with the indication of the flex points of different curves


       Yield
       (% of the
       maximum)




Based on data
                                                         ETc (%)
from Policoro,
Southern Italy




                                         Source: Venezian Scarascia et al., 1987
  Seasonal irrigation volumes for some herbaceous
  crops corresponding to the 70% of maximum yield

               Yield
               (% of the
               maximum)




  Based on data
  from Policoro,                                                                                    ETc (%)
  Southern Italy




                                                                                  Source: Venezian Scarascia
Figura 9: Andamento delle produzioni di alcune colture erbacee in relazione al volume stagionale d’irrigazione et al., 1987
                                                                                                               espresso in
Seasonal irrigation volumes of some herbaceous
crops in relation to the adopted irrigation regime
Irrigation                               Spring sugarbeet
 volume
  (m3/ha)
                                         Pepper
                                         Autumnal sugarbeet
                                         Eggplant
                                         Summer maize
                                         Spring maize

                                         Dry bean
                                         Processing tomato
                                         Shell bean




                                          ETc (%)
Studies
on

Crop
Water
Requirements
            Location
of lysimeter stations
              in Italy
Type, dimensions and number of lysimeters
used at various Italian locations
 Table 7 – Type, dimensions and number of lysimeters used in various Italian locations.
                                                                  Underground(U)
                          Surface area      Depth   Presence of
          Type                  2                                       or            Location and number
                              (m )           (m)       guard
                                                                  Aboveground (A)

 l) DRAINAGE
                                                                                    Policoro (6) Metaponto (2)
 a) groundwater
                             2x2 = 4        1,30       yes              U           Foggia (4) S. Prospero (4)
    (70-110)
                                                                                    Guiglia (4) Gela (2) Roma
                             2x2 = 4.       2,20       yes              U                  Cadriano (2)

                             2x2 = 4        1,00       yes              U           Polignano (2) Cadriano (2)

                         1,25x1,25 = 1,56   1,40        no              A                     Pisa (6)

                             1x1 = 1        1,50       yes              U                  Legnaro (20)

 b) free percolation         2x2 = 4        0,50        no              U                  Vitulazio (16)

                          2,75 m*; 5,94     1,50       yes              U                  Sassari (4) **

 2) WEIGHING
                                                                                     Policoro (2) Rutigliano (1)
 a) mechanical               2x2 = 4        1,30       yes              U
                                                                                    Gaudiano (1) Villa d'Agri (1)
 b) with loading cells     3 m**; 7,07      2,15       yes              U               Campo Volturno (4)
 * circular
 ** for tree crops
                               Variation of crop coefficient Kc’ (ETc/E)
                               of tomato grown in two Italian locations
                                                             H
                                                                      H

                                                                                   Lat. 45°12’N
                                                                                   Long. 11°58’E
Crop coefficient Kc’ (ETc/E)




                                                                                   Alt. 6 m a.s.l.




                                                                          Lat. 40°12’N
                                                                          Long. 16°40’E
                                                                          Alt. 15 m a.s.l.

                                                                                  E: emergence;
                                                    Tomato                        F1: start of flowering;
                                                                                  F2: full flowering;
                                                                                  H: harvesting



                                               Days after emergence
                                                                           Source: Tarantino and Caliandro, 1984
Variation of crop coefficient Kc’ (ETc/E)
of spring sugarbeet grown in various Italian locations

                                                               Lat. 44°35’N
                                                               Long. 11°27’E
                                                               Alt. 33 m a.s.l.
 Crop coefficient Kc’ (ETc/E)




                                                             Lat. 40°12’N
                                                             Long. 16°40’E
                                                             Alt. 15 m a.s.l.




                                    Spring sugar beet


                                Days after sowing       Source: Caliandro et al., 1980
         Variation of crop coefficient Kc’ (ETc/E)
         of maize grown in various Italian environments


                                                   Pisa (after wheat) (cl. 400)
                                                                               43°43’N

                                                   Pisa (after barley) (cl. 400)
Crop coefficient Kc’ (ETc/E)




                                                                     44°22’N


                                                                                 44°25’N

                                                                                 45°12’N

                                                                                 41°27’N


                                                                       40°12’N
                                       Maize


                               Days after sowing
                                                                          Source: various
     Variation of crop coefficient Kc’ (ETc/E)
     of sorghum grown in various Italian environments

                                                           Lat. 44°25’N
                                                           Long. 10°57’E
                                                           Alt. 490 m a.s.l.
Crop coefficient Kc’ (ETc/E)




                                                            Lat. 40°12’N
                                                            Long. 16°40’E
                                                            Alt. 15 m a.s.l.
                                    Sorghum


                               Days after sowing   Source: Caliandro et al., 1980
Variation of crop coefficient Kc’ (ETc/E)
of sunflower grown in various Italian environments



                                  Pisa (after barley)
                                                                                     44°25’
                                                                                     490 m a.s.l.
   Crop coefficient Kc’ (ETc/E)




                                                                                            41°27’
                                                              Pisa (after wheat)            72 m a.s.l.




                                                                                   44° 22’
                                                           Sunflower               30 m a.s.l.




                                                        Days after sowing
                                                                                         Source: various
Variation of crop coefficient Kc’ (ETc/E)
of soya grown in various Italian environments
  Crop coefficient Kc’ (ETc/E)




                                 Soya




                                          2nd harvest

                                                            (after barley)
                                                                             1st harvesting
                                        (after wheat)




                                        Days after sowing
                                                                                Source: ISTAT, 2002
Average Kc’ values of various herbaceous crops
in respect to the class “A” evaporation
Crop coefficient Kc’ (ETc/E)




                                                             artichoke


                               spinach
                                           potato




                                                                                               wheat
                                                                         cabbage




                               J   F     M A   M J   J   A    S O N            D J   F   M A   M J
                                                             months


                                                                                                Source: various
Relation between estimated and measured by lysimeter
crop coefficients (Kc) during muskmelon cycle cultivated with (a) and
without mulch (b) in 2001 and 2003 – Lavello (Southern Italy)




                                                             Source: Lovelli et al., 2002
Kc (ETc/ETo) values of muskmelon
cultivated under mulches and without mulches
Policoro (Southern Italy)




                                           Source: Cantore et al., 2005
Kc (ETc/ETo) values of eggplant cultivated under mulches
and without mulches – Policoro (Southern Italy)




                                         Source: Yared Tesfagaber , 2004
WUE & WP
Data
Above-ground Biomass WUE and Yield WUE of field-grown
crops under optimal conditions in Southern Italy
                           Above-
                           ground       Yield       Total
                                                             Determination
            Crop          Biomass        WUE      water used                   Location     Reference
                                                             of water used
                            WUE        (kg m-3)     (mm)
                          (kg m-3)
    Durum wheat              4.0          1.7        450
    Soybean                   -           1.0        477
    Spring Sugarbeet        8.0 a        11.0        862
    Artichoke               2.9 b        1.4 b       920                       Policoro,
                                                                weighting                    Rubino et
    Rapa                    14.0          7.8        180                        Matera,
                                                                lysimeter                    al., 1999
    Broccoli                 4.8          4.2        360                       Basilicata
    Pepper                   2.0          7.4        536
    Lettuce                   -          19.5        161
    Celery                  2.3 b       27.4 b       316
                                                                                Lavello,
                                   b                            weighing                    Rivelli et al.,
    Kenaf                    1.8                     765                       Potenza,
                                                                lysimeter                      1998
                                                                               Basilicata
    Sunflower                2.6                    891
                                                                canopy         Valenzano,    Steduto &
    Grain sorghum            5.7                    485
                                                               chambers           Bari,       Albrizio,
    Durum wheat              4.5                    230                          Puglia        2005
    Chickpea                 3.0                    320c
    Sweet sorghum            4.8 b                  532
                                                                               Metaponto,
    Kenaf                    2.3 b                  631      pan evaporation                 Losavio et
                                                                                Matera,
    Jerusalem                2.6 b                                & Kc                        al., 1999
                                                     556                       Basilicata
    artichoke
       (a)
           Roots are included.
       (b)
           Avg of more years.
       (c)
           Incomplete crop cycle.
Above-ground Biomass WUE and Yield WUE of field-grown
crops submitted to different irrigation regimes
                               Above-
                              ground       Yield
                 Irrigation                                      Determination
        Crop                  Biomass       WUE       Total                       Location     Reference
                 treatment                     -3                of water used
                                WUE       (kg m )   water used
                                     -3
                              (kg m )                 (mm)
                      I0         1.0       0.9         213
                                                                               Gaudiano,
                     I33         0.9       0.8         246                                    Candido et
     Tomato                                                      water balance Potenza,
                     I66         0.8       0.8         305                                    al., 2000
                                                                               Basilicata
                    I100         0.8       0.8         361
                      I0         1.3       2.9         195
                                                                     pan
     Sweet            IS         2.5       7.3         547
                                                                 evaporation &
     sorghum         I50         3.0       8.2         564            Kc
                    I100         3.4       7.2         826
                      I0         1.2       0.5         217
                      IS         1.8       0.6         464         weighing
     Sunflower
                     I50         1.4       0.6         534         lysimeter
                    I100         1.6       0.7         859
                      I0         1.8       0.9         176
                      IS         1.8       0.7         438         weighing
     Cotton
                     I50         1.6       0.7         421         lysimeter
                                                                                 Gaudiano,
                    I100         1.7       0.5         546                                    Tarantino et
                                                                                 Potenza,
                      I0         3.8       1.2         281                                    al., 1997
                                                                     pan         Basilicata
     Durum            IS         3.2       1.2         339
           *                                                     evaporation &
     Wheat           I50         2.6       1.0         454            Kc
                    I100         2.2       0.8         641
                      I0         1.2       2.2         281
                      IS         1.3       4.0         697         weighing
     Kenaf
                     I50         1.5       4.9         570         lysimeter
                    I100         1.5       5.0         859
                      I0         1.6       8.1         115
                                                                     pan
                      IS         1.5       8.2         359
     Tomato                                                      evaporation &
                     I50         1.3       14.4        369            Kc
                                                                                                             *avg
                    I100         1.3       13.4        635                                                          of 2 years
Above-ground Biomass WUE and Yield WUE of
field-grown crops submitted to application of fertilizers
                             Above-
                                                Total
                            ground     Yield
                                                water   Determination
              Crop          Biomass     WUE                               Location      Reference
                                           -3   used    of water used
                              WUE     (kg m )
                                 -3             (mm)
                            (kg m )
    Grain            F0                1.6      489
    sorghum          F100              1.9      466
                     F0                1.3      639
    Sugarbeet
                     F100              1.5      655                     Foggia,        Rizzo et al.,
                                                        water balance
                     F0                0.4      309                     Puglia         1990
    Soybean
                     F100              0.6      322
                     F0                1.2      298
    Wheat
                     F100              0.8      283

               *
                     F0       1.3      0.4      399                     Foggia,        Rinaldi et al.,
    Soybean                                             water balance
                     F100     1.5      0.5      408                     Puglia         1996

                     F0       2.0      0.6      538                     Foggia,        Rinaldi &
    Sunflower                                           water balance
                     F100     2.1      0.6      549                     Puglia         Rizzo, 1999

                     F0       2.2               837
    Sunflower
                     F100     2.6               891                                    Steduto &
                                                           canopy       Valenzano,
                                                                                       Albrizio,
                     F0       4.4               485       chambers      Bari, Puglia
    Grain                                                                              2005
    sorghum          F100     5.7               510
      *
          Avg of 2 years
Above-ground Biomass WUE and Yield WUE of field-
grown crops submitted to other agronomic practices
(mulching and early sowing)

                               Above-
                                                   Total
                               ground     Yield
                                                   water   Determination
            Crop              Biomass      WUE                              Location     Reference
                                              -3   used    of water used
                                WUE      (kg m )
                                    -3             (mm)
                              (kg m )
  Muskmelon                     1.7        8.7     320                      Policoro,
                                                             weighing                  Cantore et al.,
                                                                            Matera,
                                                             lysimeter                 2005
  Mulching Muskmelon            2.8       13.2     229                      Basilicata
                Normal                                       Seasonal
                                           0.7                                         Rivelli &
                sowing                                       irrigation     Matera,
  Sunflower                                                                            Perniola,
                Early                                        volume +       Basilicata
                                           1.0                                         1997
                sowing                                         rainfall
                Normal
                                4.0        1.9     457
                sowing
  Maize
                Early
                                4.5        2.3     582
                sowing
                Normal                                        Drainage
                                2.0        1.0     457
                sowing                                     lysimeter with   Pisa,      Bonari et al.,
  Soybean
                Early                                         variable      Toscana    1989
                                2.3        1.2     547       watertable
                sowing
                Normal
                                1.8        0.6     452
                sowing
  Sunflower
                Early
                                1.7        0.6     537
                sowing
    (a)
        Roots are included.
Studies
on



Deficit Irrigation
Deficit irrigation of peach tree




    phase 1 – from the start of flowering to the formation of small fruits (of 3-4 cm of diameter);
    phase 2 – from the end of the previous phase until the hardening of the kernel;
    phase 3 – from the hardening of the kernel until the harvesting;
    phase 4 – from the harvesting until the fall of the leaves.


                                                                                  Source: Mannini, 2004
Deficit irrigation
% of seasonal irrigation volumes saved by controlled water
stress on peach in respect to normal irrigation regime



          Interspace between rows cultivated       Interspace between rows grassy

SOIL                                                          Medium
           Early      Medium early     Late       Early                        Late
                                                                early
          cultivars    cultivars     cultivars   cultivars                   cultivars
                                                              cultivars

Sandy        44           38            20          38           34              20
Loam         58          59           20          52          46              23

Clay         68          56           22          60          51             23

 Data refer to the Emilia-Romagna climatic conditions
 Similar results have been obtained in the experiments on peach
  and nectarine trees under Southern Italy climatic conditions



                                                                          Source: Mannini, 2004
        Variation of maize production
        under different irrigation treatments
                                                                                                    B
                       8.0                                                                         g
                                                                                                   q
                                           AB                                                       C
                       7.0                     g              B
                                               B
                                               q              q                       B
                                               q              g
Grain yield (t ha-1)




                       6.0                                    B                   B   x
                             gA                B
                                                          B        B     B        x
                       5.0                 B
                                                          x        x x                            C
                             qA            x(s)           (s+b)
                                                                             BC
                                                                                                  u
                       4.0                                                   u
                                                                  AB
                       3.0                                         u
                                       A
                             u
                                 A      x(b)
                       2.0 x                         q q    Valenzano 1986                 s = irrigation only at sowing
                              A
                                                      g   g Valenzano 1987                 b = irrigation only at bout phase
                                                                                           s+b = irrigation at sowing and bout phase
                       1.0                           x    x Policoro
                                                     u    u Gaudiano
                       0.0
                             0                     1000           2000                    3000
                                     Seasonal volume of irrigation water (m ha-1 )
Instead of conclusion

 A huge amount of data on WUE & WP related issues is available in Italy
 More efforts should be done to make data comparable due to the
  application of different methods to determine “water used” and due to
  the use of different nominators/denominators in WUE and WP ratios.
 A more clear conceptualization of WUE and WP terms is necessary at
  regional scale.
 Standardization of procedures and normalization of ETc for evaporative
  demand of the atmosphere is needed in order to compare the
  experiments carried out in different years/locations.
 Improvement of the crop management practices in the region should
  aim at increase of beneficial water consumption (transpiration) against
  the non-beneficial losses (evaporation), i.e. on WUE & WP
    Increasing of marketable yield per unit of water transpired
    Maximizing transpiration consumption relative to evaporation losses
    Enhancing effective use of rainfall and water stored in soil
Irrigation methods in Italy




                                                  Source: ISTAT, 2002
         Figure 8. Irrigation methods in Italy.

				
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