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Irrigation and Water Resources in the Mediterranean

VIEWS: 33 PAGES: 9

									       6th Inter-Regional Conference on Environment-Water
          Land and Water Use Planning and Management
                          Albacete, Spain, 3-5 September 2003

       Irrigation and Water Resources in the Mediterranean
                  A Strategic Action Plan for R&D

                                        De Wrachien D(*)
Abstract

The combined effect of almost continuous crop water demand and natural
precipitations, which are irregularly distributed both in space and time, makes irrigation
essential in order to increase and stabilize agricultural production in the Mediterranean
environment. In the region the prospect of expanding the gross irrigated area is limited
by the dwindling number of economically attractive sites for large irrigation projects.
Therefore the required increase in agricultural production will necessarily rely, largely,
on a more accurate estimation of crop water requirements on the one hand, and on major
improvements in the operation, management and performance of existing irrigation and
drainage systems, on the other.
All this requires, among others, enhanced research and a variety of tools such as remote
sensing, geographic information systems and models, as well as field survey and
evaluation techniques. These tools have to be considered adopting a broad and
integrated approach that embraces food and agricultural commodity production, water
saving, resource conservation, environmental impacts and social-economic effects. This
approach makes up and outlines the body of a Strategic Action Plan, a crucial procedure
for implementing priority actions at both national and local levels. The Plan is expected
to bring forth clear benefits in environmental and economic terms, a more sustainable
use of land and water resources in irrigated agriculture and higher yields and incomes.
An example of a Strategic Action Plan can be found in the GRUSI (Group of Studies on
Irrigation) project, a broad based Italian Research program which stated in the 1950s
and still continues today.
With reference to these issues, the paper describes the main features and characteristics
of the GRUSI project, stresses the evolution of the prevailing trends and proposes a new
approach based on a collaboration with other national and international Organizations
involved in irrigation R&D, able to reinforce a sustainable development in the region,
balancing environmental, economic and social concerns.


   (*)EurAgEng President and Chairman Field of Interest on Soil and Water
   Director Department of Hydraulics Agricultural State University of Milan, Italy
   Tel.: +39 02 50316902; e-mail: daniele.dewrachien@unimi.it




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1. Introduction

Land and water resources development is concerned with the planning, use and
management of natural resources, primarily for agricultural purposes. To this end, the
combined effect of almost continuous crop water demand and rainfall irregularly
distributed over space and time, makes irrigation essential for increasing and stabilizing
agricultural production in arid, as well as semi-arid and semi-humid regions. Due to the
limited, and in many cases the depletion and deteriorating quality of water resources,
the need to assure an adequate and stable crop production has led to a more efficient and
rational use of irrigation water.
To achieve these goals massive investments have been made over the last few decades
by governments and individuals as well as a concerted effort by the international
community. Different scenarios have been developed to explore a number of issues,
such as the expansion of irrigated agriculture, massive increases in food production
from rainfed lands, water productivity trends and public acceptance of genetically
modified crops. Opinions differ among the experts as to some of the above issues.
However, there is broad consensus that irrigation can contribute substantially to
increasing food production. At the 1996 World Food Summit it was estimated that 60%
of future food needs would have to be met by irrigated agriculture. The International
Commission on Irrigation and Drainage (ICID) forecasts that present food production
will double within the next 25 years (Plusquellec, 2002).
The prospect of expanding the gross irrigated area is limited by the dwindling number
of economically attractive sites for new large irrigation and drainage projects.
Therefore, the increase in irrigated agriculture will have to come for a substantial part,
on the one hand from a more accurate estimation of crop water requirements and, on the
other from substantial improvements in the operation, management and control of the
existing systems.
The key reason for the failure of the present schemes and the inability to sustainably
exploit soil and water resources is poor planning, design, system management and
development. This can be attributed partly to the incapability of planners, engineers and
managers to adequately quantify the effects of their interventions in soil and water
resource systems and to incorporate them into guidelines for improving technology and
design and enhancing management.
To fully exploit the benefits of investments made in irrigated agriculture a major effort
is needed to develop appropriate technology for improving the use and management of
soil and water and for maintaining biodiversity, while conserving and protecting the
environment. In this regard, a new integrated and holistic approach to irrigation and
drainage management and monitoring is needed, to increase food production, to
conserve water, to prevent soil salinization and waterlogging and to protect the
environment and ecology. All this requires enhanced research, technological innovation
and a large variety of tools, such as automated equipment for water control and
regulation, sensors, remote sensing, geographic information systems, decision support
systems and models, as well as field surveys and evaluation procedures.
With regard to the above issues, the on-going GRUSI (Italian Irrigation Research
Group) project, which commenced in the 1950’s and involves the Italian scientific and
professional community, can be considered an important step towards launching an
internationally supported program for enhancing R&D in irrigation science and
technology in the Mediterranean region (De Wrachien et al., 2002).
With regard to the above issues, the paper first describes the salient aspects of irrigated
agriculture in the Mediterranean region. Then the main results of the GRUSI project are
outlined. Finally, the importance of institutional strengthening, sound financial and

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managerial frameworks, availability of human resources involved, research thrust,
technology transfer and networking improvement are examined

2. Agriculture in          the     Mediterranean         Environment:          Development       and
   Sustainability

    Agriculture and Land Use
Land use and distribution of agricultural land in the Mediterranean basin are illustrated
in Figure 1. As shown in Table 1, there are major differences in land use patterns from
one country to another, mainly between the Southern and the other Mediterranean
regions.
Because of the current climate patterns and intensification of human activities
Mediterranean countries are already faced with a real threat of land degradation and
desertification and there is no doubt that the present enhanced greenhouse effect will
only exacerbate this threat in the short term. The main causes of these processes can be

    Permanent Pasture
    Permanent Crops
                                                                                                 100%
    Arable land
                                                                                                 90%

                                                                                                 80%

                                                                                                 70%

                                                                                                 60%

                                                                                                 50%

                                                                                                 40%

                                                                                                 30%

                                                                                                 20%

                                                                                                 10%

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         Fig. 1. Distribution of agricultural land in the Mediterranean countries. FAO (1993a)


summarized as follows (Chisci, 1993):
    change of agricultural systems towards specialized – mechanized hill farming;
    modification of morpho – structural and infrastructural features of the cultural
     landscape concerned;
    abandoned, previously cultivated, fields and/or farms and their man-made
     structural and infrastructural elements;
    increase in forest and pasture fires.




                                                                                                       3
   Region                         Annual crops %            Permanent crops %         Permanent pastures %
   North                                57.55                       10.90                       30.89
   South                                38.60                        6.40                        55.0
   East                                 56.50                       20.50                       22.75
   Average                              50.88                       12.60                       36.22

Table 1. Land use as percentage of cultivated area in the Mediterranean. Source: Hamdy and Lacirignola (1997)
      Until the early seventies, the problem of land degradation due to erosion was considered
      of minor importance for most of the countries of the Mediterranean region (Chisci and
      Morgan, 1986), in that traditional agricultural systems had proven effective in keeping
      those processes under control. Consequently, low priority was given to research
      programs and projects on soil erosion and conservation, higher priority being assigned,
      among others, to the impact of farm machinery on soil structure and the role of organic
      matter in the soil.
      In the eighties and early nineties, global warming and the impact of the agricultural
      systems introduced in the sloping lands of the Mediterranean environment in the
      previous decades were identified as the main culprits of soil erosion and land
      degradation. Accelerated runoff and erosion, previously unreported, began to be
      observed in cultivated sloping areas. The unprecedented pressure to increase crop
      productivity at lower costs, made possible by the technological revolution in
      agricultural management, had led to soil erosion in the agricultural ecosystem, due to
      hydrological impact, resulting in severe deterioration in soil fertility and degradation of
      the landscape.
      After having thoroughly examined the problem, the scientific community concluded
      that a more detailed evaluation of the situation in the different Mediterranean
      environments was needed. Furthermore, it was recognized that research activities were
      too fragmentary to be able to cope with the demand for sound soil conservation
      measures. Another recommendation that emerged was the use of pilot areas for a
      quantitative assessment of accelerated erosion and of the effects of new conservation
      measures in the water erosion prone areas of the Mediterranean. It was also suggested
      that projects be allowed more flexibility, so that programs could be modified during
      implementation, to benefit from experience gained and lessons learned.

           Agriculture and Water Use

      In the Mediterranean region nearly 70% of the available water resources are allocated to
      agriculture. In the arid and semi-arid countries of the region agricultural water use
      accounts for as much as 80% of the water consumed, decreasing to 50% of the total
      available resources in the Northern countries (Hamdy and Lacirignola, 1997).
      Diminishing water resources in the Eastern and Southern Mediterranean are expected to
      be one of the main factors limiting agricultural development, particularly in the 2000 –
      2025 period. The water needed for irrigation is even scarcer than the land itself and land
      suitable for irrigation is becoming harder to find. At present, the irrigated areas account
      for more than 16 million hectares.
      Despite the high priority and massive resources invested, the performance of large
      public irrigation systems has fallen short of expectations in both the developing and
      developed countries of the Mediterranean. Crop yield and efficiency in water use are
      typically less than originally projected and less than reasonably achieved. In addition,
      the mismanaged irrigation project schemes lead to the “sterilization” of some of the best

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and most productive soils. Salinity now seriously affects productivity in the majority of
the Southern Mediterranean countries as well as in the coastal zones. Salt affected soils
in the region amount to nearly 15% of the irrigated lands.
Given the increased costs of new irrigation developments, together with the scarcity of
land and water resources, future emphasis will be more on making efficient use of water
for irrigation and less on indiscriminate expansion of the irrigated area..
Over the next twenty five years, substantial amounts of fresh water supplies will be
diverted from agriculture to industry and households in the region. Irrigated agriculture
will face two challenges: water scarcity and dwindling financial resources. Despite these
challenges, irrigated agriculture is expected to provide 70 to 75 percent of the additional
food grain requirements to the developing countries of the region. This will not be
possible without developing effective methodologies and systems for assessing and
improving the performance of irrigated agriculture. Such systems have to evaluate the
contribution and impact of an irrigation scheme in terms of production, self-reliance,
employment, poverty alleviation, financial viability, farmers’ profitability and
environmental sustainability.

   Agriculture: Constraints and the Strategic Action Plan

The contribution expected from agriculture can not be achieved if constraints in
irrigation and drainage systems and in agronomic practices are not adequately
addressed. In many cases technological problems and their adverse impacts on the
environment are increasing because solutions have not been found or proven effective
or because maintenance has been neglected and modernization deferred. Moreover,
modifications of natural ecosystems by irrigation and drainage networks have brought
about environmental changes commonly leading, as previously mentioned, to reduction
in water availability, waterlogging, salinization hazard and the spread of aquatic weeds.
In this regard, the main constraints inhibiting the development of irrigated agriculture in
the Mediterranean region demanding urgent attention are (Hamdy and De Wrachien,
1999):
      shortage of funds and substantial delays in their allocation;
      lack of professional and technical manpower and training facilities and
         equipment;
      lack of knowledge and research to develop new technologies and approaches
         and absence of incentives to adopt them;
      institutional weakness and lack of coordination between governmental and
         private bodies;
      lack of appropriate and consistent policies for land and water development.
These constraints tackle the root cause of the major problems encountered in irrigated
agriculture development. To overcome these hurdles suitable solutions must be devised
and translated into actions through the formulation of programs which should take into
account the actual conditions of the environment where they are expected to be
implemented. (De Wrachien, 2001).
These programs should include:
      the adoption of a comprehensive approach that integrates land and water use and
         management and environmental issues;
      the promotion of regional cooperation to ensure that the concerns of all parties
         are factored into decisions;
      the recognition of the linkages between different land uses and water resources
         availability (quantity and quality);


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    the promotion of a broad base networking system involving governments,
        professional and research institutions and non-governmental organizations;
    the endorsement of a phased program of actions at both the local and national
        levels.
This approach forms the basis for a Strategic Action Plan, which is crucial to
implementing priority actions. The objectives of the Strategic Action Plan are to:
    evaluate trends;
    assess causes and implications;
    provide an estimate of investment costs;
    establish a framework for monitoring and assessment;
    identify priority actions to address key issues.
An example of a Strategic Action Plan can be found in the GRUSI (Irrigation Research
Group) project, a broad based Italian research program which was launched in the 1950s
and still continues today.

3. The GRUSI Project

It was almost a century ago that increasing attention began to be devoted to irrigation
studies in Italy, initially as a result of several concurrent factors. The general reduction
in mean rainfall that afflicted the country between the mid 1940s-50s, made it necessary
to resort to irrigation to boost food and fiber production. Meanwhile, scientific and
technical progress enabled scientists and professionals, in Italy and abroad, to benefit
from significant technological improvements (such as advances in pumping equipment
followed by innovations in sprinkler systems, the huge modern irrigation facilities and
finally, the introduction of dip irrigation). The urgent need for knowledge sharing in this
field, through an interdisciplinary approach involving scientific, political and economic
contributions and for exploring the possibilities of transferring lessons learned and
experience gained, provided a major impetus to irrigation research immediately after the
2nd World War.
Since the project was launched, the main research trends have changed gradually over
the years (Cavazza, 1998). In the early years the accent was on the crop response curve
to watering depth and frequency, irrigation methods and crop growth stages. The
interest in these topics gradually diminished as suitable procedures for solving the
problems were defined, tested and commonly practised by the scientific and
professional community. During the 1970s, the attention was turned to comparing and
assessing irrigation system efficiency and to field techniques for evaluating:
     inflow and outflow rates and volumes;
     timing of irrigation, particularly premature initiation and termination;
     soil water characteristics and crop water requirements;
     slope, topography and geometry of the fields.
Another topic researched by a joint team of agronomists and hydraulic engineers that
led to major developments in this area, focused on the behaviour of the unsaturated zone
and concerned flow and transport phenomena in the soil – plant – atmosphere system.
Topics such as plant resistance to salinity, osmotic adjustment to water stress, rooting
depth and soil – water properties versus moisture content, were thoroughly investigated
by means of both laboratory and field plot tests as well as simulation models. To
understand and control these processes a major effort was launched aimed at unravelling
the complexity of various interactive physical, chemical and microbiological
mechanisms affecting unsaturated flow and transport by scientists from different
disciplines.


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The 1980s saw a growing interest in investigating methods for evaluating crop
evapotranspiration rates using both lysimeter measurements and the FAO Penman –
Monteith equation. Topics related to irrigation management, such as groundwater
contribution to the water balance, field measurements of water distribution systems, the
use of irrigation for non conventional purposes (fertigation and temperature regulation),
the adverse impact of using low quality waters (wastewater and/or brackish water) for
irrigation, waterlogging and the salinity risk, also received increasing attention. More
recently, the operation and management of large irrigation systems (center – pivot
systems, linear – move systems and so on ) on the one hand, and environmental issues
on the other, have been gaining ground, along with the application of geostatistic and
remote sensing techniques to irrigated agriculture and aspects of advanced soil physics
such as the role of macro-pores and cracking in swelling soils.
The scientific results of GRUSI’s activities are documented by hundreds of papers,
reports, lectures and in – depth reviews written by researchers and professionals which
have been presented at national and international workshops, seminars and conferences
on a variety of irrigation-related issues including soil physics, plant physiology, agro-
meteorology and agricultural climatology, agricultural hydraulics and agronomy. On the
whole the GRUSI has made a valuable contribution to research in the widely varied
sector of irrigation science and technology, covering all the basic and application-
oriented topics and exploring them, from insights into basic science to on-farm and off-
farm maintenance and operational aspects, from system design and management to
economic and environmental issues.
Although there has been a substantial increase in research in these fields over the past
decades, much still needs to be done in order to improve our ability to understand the
phenomena involved, predict and control the effects of both human activities and
climate patterns on irrigated agriculture and find solutions for maintaining a sustainable
use and development of natural resources. Unfortunately, segmented disciplinary
research has, in some cases, hampered the ability of researchers and professionals to
factor the results achieved into criteria, concepts, parameters, operational – ready – to –
use formulas. So, challenges for both basic and applied research remain, as does the
urgency for progress, inasmuch as the soil and water resources are increasingly
threatened by pollution and over-exploitation. Meeting these challenges demands new
and specific advances in our ability to manage and protect the rural environment.
With regard to the above problems, the GRUSI project has played and continues to play
an increasingly important role at both the national and international level, thanks to its
links and cooperation with other regional and world-wide frameworks (CIHEAM,
EurAgEng, FAO and ICID), through capacity building, facilitating information
exchange, supporting the activities of technicians and farmers and aiming to provide a
forum for the state – of – the – art presentation of relevant methodologies and the
identification of needs for future R&D.

4. Concluding Remarks

 Agricultural development is expected to play a major role in achieving food security
  and improving the quality of life, especially within the context of meeting the food
  needs of the growing population in the Mediterranean basin. In the past, agricultural
  production was accomplished through expansion of the land under cultivation.
  Nowadays, there are clear signs that many parts of the region have already reached
  or are fast approaching limits to area expansion. This reality poses natural
  constraints to development. Beyond these constraints man dictates the pattern of


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  future trajectories. If the strategies adopted are environmentally sound, it will be
  possible to increase agricultural production on a sustainable basis.
 Concerning irrigated agriculture, most of the current 16 million hectares of irrigated
  land were developed on a step by step basis over the centuries. Many structures of
  these systems have aged or are deteriorating. They are, moreover, under various
  pressures to keep pace with changing needs, demands and social and economic
  development. Therefore the infrastructure in most irrigated areas needs to be
  rehabilitated, renewed or even replaced and consequently redesigned and rebuilt, in
  order to meet the goal of improved sustainable production. This process depends on
  a set of common and well-coordinated factors, such as new advanced technology,
  environmental protection, institutional strengthening, economic and financial
  assessment, research thrust and human resources development. Most of these factors
  are well-known and linked to uncertainties associated with climate change, world
  prices and international trade. These uncertainties require continued attention and
  suitable action on many fronts, in order to promote productivity and facilitate
  flexibility in agricultural systems. Therefore, water system engineers and managers
  should begin to systematically review existing design criteria, operating rules,
  contingency plans and water allocation polices. To this end, strategies need to be
  developed that ensure maximum productivity per unit of water and land, while
  reducing the use of fertilizers and pesticides to improve efficiency in order to
  preserve the environment.
 A major gap exists between desired water use efficiency and that actually achieved.
  Filling this gap requires:
       controlled drainage water table management to conserve water and improve
          the quality of drainage effluents;
       improved operation and maintenance of irrigation and drainage systems;
       rehabilitation and modernization of irrigation and drainage systems
          involving the reconstruction of water intakes, sediment protection, automatic
          control equipment, pumping stations. In a number of cases this process will
          be associated with the need to meet the technological changes to irrigation
          and drainage facilities, including all supplementary devices and attachments;
       improved watering techniques such as furrow and dip irrigation instead of
          traditional flooding;
       adoption of water conservation techniques like tillage, to reduce evaporation
          from land and/or modifying planting dates to match periods of low
          evaporation rate;
       increased use of efficient sprinkler and micro irrigation systems to replace
          open gravity flow so as to apply water more uniformly, introducing the low-
          energy-precision application-systems already developed to reduce
          evaporation and wind-drift losses;
       improved irrigation scheduling and canal operation to ensure supply at the
          most crucial times for crop yield;
       promotion of agronomic research and application of results such as:
               - selecting crop varieties with high yield per unit of water;
               - switching to less water intensive crops;
               - sequencing crops to maximize output under conditions of soil and
                  water salinity;
               - selecting drought resilient crops where necessary;
               - introducing water efficient crop varieties.
       privatization of the existing irrigation and drainage systems in the Eastern
          Mediterranean European region. The systems should be split up into smaller

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          units wherever the nature of the facilities allows. The smaller units obtained
          should be of a size sufficient to supply agricultural corporations or the
          associations affiliated thereto;
       introduction of institutional reforms including:
              - establishing water user organizations for increasing farmer
                  invovement in the management and collection of water fees;
              - reducing irrigation subsidies and/or introducing conservation-
                  oriented pricing;
              - strengthening training and extending services to disseminate efficient
                  technologies;
       involving private sector companies in marketing or developing such
          technologies.
 The actions and activities described above emphasize the need for national and
  international institutions to foster irrigated agriculture development. To this end, the
  establishment of an effective networking system can greatly facilitate collaboration
  and integration. The nodes of the network will be organizations, institutions and
  agencies, as well as professional, academic, commercial and industrial bodies.
  Within this frame the GRUSI project is playing an increasingly important role
  because of the wide variety of disciplines involved in irrigated agriculture in the
  Mediterranean environment, as well as elsewhere, and represents a unique
  opportunity for the Italian scientific community to prove to its partners its ability to
  speak authoritatively from scientific and technical standpoints.

References

Cavazza, L. 1998. Evolution of GRUSI over time. Proceedings of the Conference on
Irrigation and Research. Progress in the Use of Water Resources. Bari, Italy.
Chisci, G. 1993. Perspectives on soil erosion protection in the Mediterranean.
Proceedings of the Workshop on Erosion in Semi-Arid Mediterranean Area. Taormina,
Italy.
Chisci, G. and Morgan, R.P.C. (Eds). 1986. Soil Erosion in the European Community.
Impact of Changing Agriculture. Rotterdam, the Netherlands.
De Wrachien D. 2001. Irrigation and drainage. Trends and challenges for the 21st
century. Proceedings of the 19th ICID Regional Conference on Sustainable Use of Land
and Water. Brno, Czech Republic.
De Wrachien D., Caliandro A., Cavazza L. and M.E. Venezian Scarascia 2002.
Irrigation R&D in the Mediterranean Environment. The Role of the GRUSI Project.
Proceedings of the ICID International Workshop on Crop Water Management for Food
Production Under Limited Water Supplies. Montreal, Canada.
Hamdy, A. and De Wrachien, D. 1999. New policies and strategies on land and water
development in the Mediterranean region. Proceedings of the 2nd Interregional
Conference on Environment-Water. Lausanne, Switzerland.
Hamdy, A. and Lacirignola, C. 1997. Use of water in the Mediterranean. Sectorial
distribution and prospects. Séminaires Mèditerraneenes, Série A n. 31, Valenzano, Italy.
Plusquellec H. 2002. Is the daunting challenge of irrigation achievable?. ICID Journal
vol. 51, n 3.




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