Irrigation Sustainability in the Land Use/Soil System in South Italy: Results from a GIS Simplified Approach and Future Methodological Developments - Water and Agriculture: Sustainability, Markets and Policies - page 254

SWAP model will use historical climatic series (daily average Temperature and
cumulative Rain data) of almost 20 years, reference crops, benchmark soil profiles, single
irrigation technique and water volumes.
The results will consist of the minimum optimal irrigation volume values per test
representative sites, that will be used for final calibration of the real water crop
requirements (Rwcr), and the validation of the IEff values for all the Southern Italy.

3. Results and conclusion

Thanks to the integrated use of different cartographic layers, and on the basis of
F.A.O. standard, the irrigation suitability of the soil of the South Italian Land
Reclamation Consortia irrigated areas has been defined. This data are organised in a GIS
data base, and are geographically linked to the irrigated land use layer , which contains
information on irrigation techniques and nominal water crop requirement (NCWR).
Based on the irrigation soil suitability data an Irrigation economical and technical
Efficiency Index (Ieff) has been derived. This index, defining the efficiency of irrigation
water use per crop/soil/irrigation technique, allows to calculate the extra amount of water
used per hectare due to an inefficient water use (in Table 9 and 10 ). This

value has been applied on the whole irrigated surface inside the Consortia waterworks
equipped area, obtaining the total extra amount water (

￿+,-￿#

)
per Consortium (see an example in Table 9) and per Region (see Table10). The data of
the total

￿￿+￿,￿-.

in Southern Italian Region (425228118 mc) represents about the 34 % of
the total CWR, more or less the same quota of the unitary value (1039.6 mc/ha).
The

￿+,-

"￿￿￿￿
average unitary irrigation water cost of 0.052/m 3 ), but, with appropriate rural and
agricultural policies it should be considered as saveable water for irrigated area
expansion, or for other uses.
Particularly attention has to be paid on the opportunity of expanding the irrigated
areas already equipped with irrigation waterworks, but that are actually non irrigated for
lack of water. Presently the ratio between areas equipped with irrigation waterworks and
irrigated areas is very low in several Consortia (in Table 10: Pipeline use % is about 50 %
in the whole area).
The average irrigation waterworks cost per hectare/year, obtained joining public
(adduction and distribution pipelines, plus waterworks nodes) and private investment,
estimated in 797 and 1188

￿+,- is at present wastewater or waste money (about 22 M

, respectively for rolls and sprinkler and micro-irrigation
tools. According to the lower value (the sprinkler technique is the most diffused), the total
cost of the infrastructure on the total area equipped with irrigation waterworks is
653267872

"#

. But taking into consideration only the irrigated area, the unitary
irrigation investments cost rise to 1597

"#

"# /ha.