CONTENTS INTRODUCTION INTRODUCTION... 1 SALINISATION PROCESSES... 2 AREAS AFFECTED AND PRONE TO SALINISATION... 4 CAUSE AND EFFECT RELATIONSHIPS...

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3 INTRODUCTION CONTENTS INTRODUCTION... 1 SALINISATION PROCESSES... 2 AREAS AFFECTED AND PRONE TO SALINISATION... 4 CAUSE AND EFFECT RELATIONSHIPS... 6 IMPACTS ON AGRICULTURE... 7 MITIGATION AND ADAPTATION MEASURES... 8 RESEARCH APPROACHES TO DEAL WITH THE SALINISATION ISSUE CASE STUDIES Salinisation in Spain: The Vélez River Coastal Aquifer (Spain) Salinisation in Cyprus: the Akrotiri peninsula Salinisation in Italy: the Licata Plain area FINAL CONSIDERATIONS REFERENCES AND FURTHER READING Salinisation is one of the key processes that can lead to desertification. It is a growing phenomenon all over the world and affects millions of hectares across Europe. Agriculture plays a major role in driving the phenomenon, by causing high water consumption and water chemical degradation, but at the same time it is the economic sectors that are facing the strongest impacts. The effects of salinisation for farmers can be dramatic in both economic and social terms. Moreover current climate change scenarios, with the suggested temperature increase and sea level rise could significantly increase salinity and result in the expansion of the affected areas. The aim of this booklet is to share the knowledge accumulated in many European projects, about soil and water chemical degradation, and to increase the awareness of how crucial salinisation could be in the near future. To do this we think it is necessary first of all to understand what salinisation is, and then to describe how to measure and monitor it. We will also try to provide the reader with an up to date overview of the affected areas in Europe. The booklet then turns to the identification of causes and effects, and to the impacts on the different economic sectors. The last pages provide information on how to adapt and/or mitigate soil and water salinity and describe some case studies that are good examples of local strategies to deal with salinisation. 1 Figure 1 Links between the Lucinda Salinisation Booklet and the other items

4 2 SALINISATION PROCESSES The term salinisation is used for the process of salt accumulation in the soil. It occurs especially in arid and semiarid areas where soluble salts precipitate within or on the surface of the soil. How to measure salinity? Whenever we collect data or read the literature about salinisation we face the difficulties of comparing different research results or data due to the use of different ways to measure salinity. Scientists and technicians are used to dealing with different units of measurement, but for the layman it is not immediately obvious how to compare the different measures. Salinity is a measure of the quantity of dissolved salts in water, and is traditionally measured in parts per thousand (ppt, or ) or as Total Dissolved Solids (TDS). TDS is the concentration of a solution as the total weight of dissolved solids. (1 ppm = 1 milligram/litre, and 1 ppt=1 gram/litre) More often salinity is calculated from the conductivity of the solution. As a general rule, the higher the salt concentration in a solution, the better is its ability to conduct electricity. Electrical conductivity of water (ECw) is nowadays expressed in units such as decisiemens per meter (ds/m). Rain water, for example, has a conductivity of 0.02 ds/m, while sea water has a conductivity of ds/m. TDS and conductivity are not linearly related, two solutions with the same TDS could have a different ECw depending on the different types of ionic salts and their concentration. A generally accepted rule of thumb to convert TDS to conductivity is: TDS (ppm) = conductivity (ms/cm) x It is common to find other measurement units such as mho/cm, or to meet submultiples such as ms (millisiemens) or µs (microsiemens). Table XX above will help to avoid confusion. The Siemens is the official unit for conductivity used in the Metric System while mho is an older unit commonly used in North America. Key definitions The term salinisation is often linked to other key words such as sodicity, or acronyms like SAR and ESP. It is important to understand the exact meaning of these terms and acronyms. The term sodicity is used when an excess of exchangeable sodium causes the dispersion of soil particles. In sodic soils the amount of sodium held onto clay particles is 5% or more of the total cation exchange capacity. ESP (exchangeable sodium percentage) indicates the amount of sodium ions that can be exchanged in a clay soil. A high ESP is an indication of a sodic soil. SAR index (sodium absorption ratio) provides information about the amount of sodium in the water and the associated risk of causing soil sodicity. It is expressed by the ratio of the sodium ion concentration ([Na]) in the soil solution to the square root of the total divalent ion concentration ([Ca]+[Mg]). A high SAR of waters used for irrigation increases the risk of soil sodicity. Waters with the same ECw but different SAR can have different effects on both plants and soil physical characteristics. Figure 2 Units of measurement for salinity Increasing salt levels in the top soil layers can negatively affect plant growth and productivity to the point of plant death. High concentrations of various salts (e.g., sodium chloride, magnesium and calcium sulphates and bicarbonates) affect plant growth both directly, through their toxicity, and indirectly, by increasing osmotic potential and lowering root water uptake. In dry clima-

5 tes continuous salt accumulation can lead to desertification, while in humid or subhumid climates moderate or severe salinisation may occur seasonally. Salt soil accumulation is the end product of several different processes. Thus, the term salinisation may include different processes driven by different causes that bring about the same result. Generally speaking, we can distinguish primary salinisation, due to natural soil characteristics, and secondary salinisation where human activities play a central role. Basically, salinisation occurs where, depending on the soil and groundwater table characteristics, the equilibrium between rainfall or irrigation and evaporation is moved towards evaporation. We can identify three main processes that can cause salinisation: the rising of the water table to, or close to, the ground surface: it occurs in non-irrigated drylands where salts accumulate by water evaporation in the top soil surface; the excessive use of water for irrigation in dry climates, with heavy soils, causes salt accumulation because they are not washed out by rainfall; the intrusion of saltwater: this occurs in coastal areas where seawater replaces groundwater that has been over-exploited. The first process occurs in alluvial plains or depressions in semiarid regions when groundwater levels are close to the soil surface. Capillarity sucks water to the surface where it evaporates due to the intense solar radiation, leaving behind deposits of salt. In those soil types we can often observe salt crusts. The second process occurs in cultivated areas where irrigation is associated with high evaporation rates and a clay texture of the soil. In this context salt leaching is scarce or absent and sodium magnesium and calcium ions accumulate in the soil surface layers. The last process occurs in coastal areas where excessive extraction of water, due to multiple demands, causes the lowering of the water table and the intrusion of sea water. In recent years, this process has spread dramatically throughout Mediterranean coastal areas. Increased salinity from groundwater affects productivity of irrigated crops and, in a medium to long-term perspective, contributes to secondary soil salinisation. However, moderate soil salinisation is reported even in areas irrigated with good quality water depending on irrigation methods and aridity conditions, while salinisation may not occur in areas where farmers have relied on salt-rich water for years. These two examples clearly show that in each area potentially affected by salinisation a different and peculiar equilibrium between the different factors influences the salinisation process. Other processes can cause salinisation and will be briefly discussed in the following pages. 3 Figure 3 Showing relationships between rainfall, evaporation and soil

6 AREAS AFFECTED AND PRONE TO SALINISATION Salinisation is a worldwide issue. The FAO Unesco assessment in 1999 showed that saline soils and sodic soils are widespread and affect millions of hectares of land all over the world. Different estimates have been produced showing that a significant percentage of salt affected soils are human induced. In 1998, the second environmental assessment of the European Environmental Agency reported that about 4 million hectares of European soils were affected by salinisation, mainly in the Mediterranean countries. Four years later, in the third assessment, the total amount of soil affected was about 16 million of hectares. This new assessment, however, included countries, such as Russia, that were not considered in the previous report, so that the data are not directly comparable. The same source shows that in the Mediterranean area 25% of irrigated cropland is affected by moderate to high salinisation. Another updated source of data is Europe s water: an indicator based assessment, published in 2003, where saltwater intrusion is evidenced in different European countries, particularly Spain, Italy, Greece and Turkey. Maps clearly show a strong connection between the water exploitation index and areas affected by salinisation. It is clear that many of the areas where an intense littoralisation process has occurred are the same as where we are now facing salinisation. 4 Figure 4 Map showing changes in water availability. Source: EEA Eionet IRENA

7 Figure 5 Map showing the clear link between seawater intrusion and groundwater over-exploitation Source: EEA Eionet IRENA Figure 6 Greenhouses Almeria, Spain

8 CAUSE AND EFFECT RELATIONSHIPS In previous paragraphs we identified three main processes that can cause salinisation. However, it can occur in specific areas for other natural or human induced causes. Agronomic practices like overuse of fertilizers, especially over a long period of time, can contribute to increased ionic concentration of soil solutions, or misuse of machinery can lead to soil compaction, causing poor drainage. Poor land levelling may result in salinisation of the lower slopes and valleys, as the water table is closer to the surface and is subject to capillary action. Moreover in windy coastal areas marine aerosols can drive salts far inland from the coastline, far more than fall to the soil in rain. The causes can be different but the final result is the accumulation of salts in the top soil surface (0-40 cm) that reduces the ability of crops to take up water and concentrate ions toxic to plants. Nowadays one of the main cause of secondary salinisation is the use of saline waters for irrigation etc. where seawater has intruded into the aquifers. Groundwater salinisation is a growing issue along European coastal areas. Agriculture plays a major role in water extraction and consumption especially in Mediterranean coastal areas where intensive irrigated horticulture is widespread. Nevertheless, in many areas a large contribution to aquifer overexploitation is due to the industrial and residential sectors and, seasonally, to tourism. DPSIR conceptual framework for salinisation Driving forces Industry Agriculture Tourism Households Human settlement growth Pressures High water consumption Groundwater over-exploitation State Surface water quality, quantity Soil chemical quality, soil structure Groundwater status Impacts Groundwater levels Saltwater intrusion Soil salinisation Low crop yields Abandonment of non tolerant crops Farmer income reduction Land abandonment Desertification Responses Alternative supplies (dams, pipelines) Water use restrictions Regulations Water contracts agreements Desalinisation Crop tolerance improvements Water saving techniques 6 Figure 7 Irrigation Alentejo, Portugal

9 Several different indicators have been proposed to assess and monitor salinisation throughout Europe, but discussion is still underway to select the parameters and/or indexes that can best characterise, measure and monitor how the process evolves over time and space. Below, we list some examples of indicators related to the salinisation processes (irrigated areas, water consumption, water exploitation index, etc). No single indicator is able, by itself, to provide enough information about the process. At the same time we have to deal with an heterogeneous availability of data between countries and inside countries, so we do not yet have a clear picture of the situation and of its dynamics. IMPACTS ON AGRICULTURE The degree of salinisation and salt type affects the range of effects that can be observed on crops. Generally, productivity is not affected by low level salinity, but a sudden drop in productivity is observed after a species-specific threshold is crossed. Crop species can be ranked according to their tolerance to salinity, with cereals being generally more tolerant than horticultural or fruit-tree species. The economic impact of salinisation is not easy to evaluate because of the nonlinear relation between salinisation and productivity. Thus, salinisation may remain undetected for years at moderate levels of salinity, while a further increase may cause land abandonment in a few years. Table 1 Tolerance of crops to salinity 7 Figure 8 Showing Crops productivity dynamic at different levels of salinity

10 MITIGATION AND ADAPTATION MEASURES With regard to salinisation, agriculture plays a double role as both the first and the last element of the causal chain. On the one hand, it increases pressures on soil and water resources, while on the other hand it has to deal, by mitigation and adaptation strategies, with the damages originally caused by itself. Farmers are adapting to increased soil and water conductivity by a mixture of strategies that include better choice of crops and cultivars, rotation, irrigation methods, water storage, water mixing, water reuse, and desalinisation. No single option is able to ensure that productivity levels and income are maintained over time. Prevention and reclamation of salt-affected soils requires an integrated management approach including monitoring, agronomic and technological measures,and consideration of socioeconomic aspects. Moreover, actions to fight or mitigate salinisation can be implemented by local institutions and research stations, while research and technology transfer can play a crucial role in providing tools, setting up management strategies or spreading water-saving techniques. In the following pages we list and discuss different measures and responses from three different points of view: institution, farm and research. A Decision Support System (DSS) function for water resources management makes it possible to test different options and simulate impacts for the different land systems, addressed to public administration and land planners. It is implemented on the basis of real needs and current data availability. The DSS is a useful tool for the integrated assessment of policy and planning interventions aimed at mitigating desertification/salinisation and used by policy makers and planners active at the local and the watershed level. The DSS is based on a numeric simulator capable of taking advantage of GIS data and functions, including the integrated use of Land Capability and Land Suitability for soil, water and vegetation resources management. It is able to simulate the impacts of a local action plan. The DSS furnishes a user-friendly interactive graphic environment. It is able to assess environmental impact in terms of interaction between desertification/salinisation and land management, considering both environmental and socioeconomic points of view. Institutional level policies on water resources management to deal with or prevent salinisation Dynamic knowledge of: Water resources availability and their use Stock and distribution water systems (infrastructural facilities) Best practices to improve the water use efficiency, in terms of modality, time and needs Adaptation, Mitigation and Recovery actions for combating desertification by means of Decision Support Systems (see BOX) Responsibility for security and control in water supply (illegal theft of water) Water agreements between different economic sectors and stakeholders Desalinisation Water storage Traditional knowledge and techniques for water resource management Dry farming techniques: crop and cultivar choices, see Figure The main strategies that farmers use to mitigate and adapt to salinisation Irrigation systems Water and soil agronomic conservation measures Figure 9 Intensive horticulture, in temporary greenhouses fed by ponds

11 Figure 10 Alternating rainfed durum wheat with irrigated horticulture under tunnels to avoid salt accumulation 9 Figure 11 Alternating rainfed winter crops (artichoke) with irrigated horticulture under non-permanent tunnels

12 10 RESEARCH APPROACHES TO DEAL WITH THE SALINISATION ISSUE Research activity crosses all the themes mentioned above. Crop tolerance improvement is the most important topic, for example, to tackle some effects of climate change on the basis of the future scenarios. In terms of agricultural yields the future climatic scenarios for 2050 predict a loss of production of about 20% in the South Europe, caused in particular by: 1. reduction of the plant growing period; 2. extreme events becoming more frequent during the phenological phases, in particular heavy rains during the seed germination, heatt stress during flowering; 3. A more intensive and longer drought period For these reasons water conditions will be more and more critical and the salinisation processes will increase. So, the selection of cultivars more tolerant to drought and saline stress (see BOX) is one of the most important strategies of biotechnological research to deal with salinity. Figure 12 Sunflower Alentejo, Portugal Adverse environmental stress, such as high salinity, has a strong influence on agricultural production and sustainability. The study of the mechanisms involved in plant response and tolerance represents a major challenge for plant scientists especially in the light of predicted global climate changes. Scientists are following different ways to tackle these challenges, such as: increasing the knowledge of species population variability; exploring new genes in species closely related to cultivated crops; understanding physiological responses to the abiotic stress; mobilization of plant resources and seed collections of halophytes as fodder plants for utilization in the phytomelioration. Plant genomic research is beginning to provide information related to possible mechanisms involved in abiotic stress tolerance, such as an increasing number of genes, transcripts and proteins that are being implicated in stress response pathways. The expression of the stress-related genes is induced by the binding of dehydration-responsive transcription factors (DREB) to the DRE motif in the promoters of various drought, salt and cold stress genes, thus exerting a regulatory role in modulating plant response and possibly tolerance. The isolation and characterisation of homologous DREB genes are currently underway in various plants, including barley, wheat, rice, maize, soybeans and also carrots and tomatoes, and the use of DREB over-expressing transgenic yeast and plants is yielding more information about their biological role and possible downstream target genes. Another approach is oriented to the mobilization of plant resources and seed collections of halophytes as fodder plants for utilization in the phytomelioration. Desertified saline land can be restored even if highly saline, by suitable halophytes or halo-tolerant plant species. Introduction of ecological restoration is an effective technology for degraded lands. It has great economical and ecological value for biodiversity, conservation, restoration of degraded ecosystems as well as the productivity and control of desertification.

13 CASE STUDIES Salinisation in Spain: The Vélez River Coastal Aquifer (Spain) The Río Vélez fluvio-deltaic aquifer is situated below the Mediterranean coast of Andalusia, Spain, and extends over the lowest sector of a 610 km 2 watershed. The economy of this region is based on tourism and agriculture (especially subtropical and out-of-season crops). The irrigation surface is slightly larger than 40 km 2. The population is over 60,000, but it can increase to about 150,000 during the summer tourism period. The climate of the area is typically Mediterranean. Average temperature is around 18ºC and average precipitation is around 600 mm/year, with rainfall concentrated between November and April. Rainfall is both highly variable and seasonally most scarce when water requirements are higher. In the headwater area of the basin, the fissured carbonate rocks make up an aquifer which is drained by a number of springs located in its borders (figure 13). These springs form the baseflow of the Vélez River. The Vélez River aquifer is made up of quaternary deposits (mainly gravel and sand) that extend over about 20 km 2. In the coastal part of the aquifer, Pliocene silts and silty clays with very low permeability form an elevation in the substratum which has an altitude close to sea level. As a result, two sectors of the aquifer can be easily distinguished: the fluvial sector and the coastal sector. The two sectors can become independent during times of severe drought due to general piezometric decrease. This situation is advantageous from a hydro-geological point of view as it makes it impossible for a salt water wedge to intrude inland into the fluvial sector. The aquifer is mainly recharged by the streamflow of the Vélez and Benamargosa rivers. The water from irrigation returns also contributes. The main discharge from the system corresponds to groundwater withdrawal in over 400 wells, with an average of 3,000 m 3 /year, to which surface and groundwater discharges into the sea along the coastline must be added. During the 1970s and 1980s water demand was satisfied by uncontrolled pumping of the aquifer. At the same time, an alternative was conceived and a reservoir system (La Viñuela) was built. Since the La Viñuela reservoir started functioning in 1989 and the streamflow from it was reduced or even eliminated, the coastal aquifer has experienced a decrease in its recharge. This fact, together with the scarcity of rainfall in the first half of the 1990s and the increased groundwater extractions, led to a considerable decrease of the piezometric levels in the aquifer. During the summer of 1995, a significant advance of the salt water wedge was registered and the water shortage due to the severe drought was aggravated by deterioration in the water quality, causing urban supply problems and losses in some crops. The increased rainfall recorded during the period considerably improved this situation. The volume of water in the La Viñuela reservoir almost reached its maximum capacity in Spring The piezometric levels rose quickly and the salt water wedge flushed significantly. During the last few years, the reservoir has supplied water for both irrigation and urban use, thus the pumping of freshwater from the aquifer has almost stopped. At present, the aquifer presents no evidence of significant marine intrusion, but an outflow from the dam sufficient to maintain a subterranean discharge to the sea is necessary in order to get a long-term control of this problem. In addition, intensive agriculture and the application of high doses of fertilizers may cause a deterioration of groundwater quality, associated mainly with nitrates. Figure 13 Location of the Río Vélez aquifer and its watershed. (from Benavente et al., 2005) 11

14 12 Salinisation in Cyprus: the Akrotiri peninsula The Akrotiri peninsula and aquifer are located along a peninsula on the southern coast of Cyprus (Figure 14). Covering an area of 42 km 2 of heterogeneous unconsolidated delta sediments and intercalated marine deposits, it is delimited by mountain ranges on its northern side, by a depressed salt lake on the south, and by the Mediterranean Sea on the eastern and western sides. The peninsula is characterized by a semi-arid climate, with evaporation, on average, more than double the rainfall (450mm/year). The rainfall is mainly concentrated in the winter months; at other times the peninsula suffers, as does the rest of the country, from water scarcity due to structural and seasonal water shortages and high rates of population growth associated with the increasing influx of tourism. Akrotiri is the third largest aquifer in Cyprus and the most important water resource in the area, providing local farmers with irrigation water as well as supplying a considerable part of the water for the domestic needs of the city of Limassol, the local villages and the nearby British military base. The Akrotiri aquifer is naturally replenished through infiltration within the Kouris riverbed, local rainfall and return flow from irrigation. In the late 1930s a large citrus plantation (11 km 2 ) was initiated on the central part of the aquifer, making this area an important agricultural plain. Since then, large amounts of water have been extracted for domestic use and irrigation purposes (on average 14 million m 3 /year between 1967 and 1977), causing seawater intrusion and salinisation problems. Furthermore, in the last few decades, the water demand has grown because of the increased agricultural activity and the booming tourism. For these reasons, in 1987 the authorities decided to construct the Kouris river dam with a capacity of 115 million m 3. Cutting off the main source of replenishment, the dam changed the hydrologic regime causing a drastic reduction in the natural recharge of the alluvial aquifer and consequently a lowering of the water table below mean sea level over large areas. This, in conjunction with the uncontrolled and excessive pumping, has led to the seawater front moving inland up to 2 km, in particular in the western part of the peninsula. Additionally, water quality in the aquifer began to deteriorate further because of the intensive use of fertilizers and pesticides in agricultural production in the area. By the early 1990s, with an average exploitation rate of 18 million m 3 /year, the problem had become alarming, leading to the salinisation of the irrigated land and causing the farmers to modify their agricultural practices and abandoning coastal crops and several wells. More lately, the aquifer has been declared a conservation area by the authorities, and exploitation has been first reduced to 12 million m 3 /year on average, and further diminished to 7 million m 3 /year in the period At present, to enable the efficient and sustainable management of the aquifer only limited extraction is permitted and water meters are installed in all wells, while irrigation demand for citrus plantations and seasonal crops mainly relies upon a very costly irrigation system which conveys surface water from the Kouris river dam. In additon, in order to mitigate the adverse effects of reduced water availability and deteriorating water quality in the aquifer, there is artificial recharge with water from the upstream dam or from a sewage plant. This is done through three infiltration ponds, which were constructed in the area of the fruit farms and in the former Kouris riverbed, whenever water excess is recorded either in the Kouris dam or in the smaller Yeramasoya dam, during winter time. Figure 14 The Akrotiri Peninsula, Southern Cyprus, showing the boundary of the Akrotiri aquifer with respect to the main villages, the most important plantations, the Kouris and Garyllis rivers and other features (dams, salt lake). (From SWIMED website)

15 Salinisation in Italy: the Licata Plain area Licata is located in Sicily, one of the regions most severely affected by desertification in Europe (figure 15) Salinisation and erosion are the main processes affecting the area and are strictly linked to the intensity of land use (figure 17). Greenhouse expansion to produce high value vegetables for the national market strongly increased groundwater abstraction from the 1960s to reach critical levels Nowadays intensive farming is the main economic activity in the area, while planned tourism development could increase water consumption Farmers have developed a mix of strategies to deal with low water quality and to maintain their income The Licata Plain is an intensively cultivated area in the Agrigento province (Sicily). The local economy is mainly based on horticultural production: specifically melons, tomatoes, zucchini and artichokes. The Licata plain is included in the Imera river basin that crosses the central part of Sicily where naturally salty soils are widespread. The river shows strong variation in salinity over time and the water cannot not be used by farmers for agriculture due to its high salinity levels. In the Licata plain there are more than 2000 wells, legal and illegal, used by farmers to irrigate their permanent or temporary greenhouses. The average ECw of 100 hundred wells measured in 2004 was 5,9 ms/cm, corresponding to a degree of salinity that makes it very difficult to use the water for irrigation. This high salinity level affects productivity of irrigated crops and, in a medium- to long-term perspective, could contribute to secondary soil salinisation. The agriculture sector plays a double role: on the one hand it is increasing pressures on soil and water resources, on the other hand it has to deal, by means of mitigation and adaptation strategies, with damages caused by itself. In Licata, after more than 40 years of intensive use of saline water resources, agriculture activity still goes on thanks to aridity-culture techniques. Licata farmers are adapting to increasing soil and water conductivity by a mix of strategies that include crop and cultivar choice, rotation, irriga- 13 Figure 15 Licata basin

16 tion methods, waters storage, waters mix, desalination. Moreover, water management takes into account the quality improvement of some products (in particular tomato and Cantalupe cucumber) that can be obtained using moderately salty water. No option is able by itself to ensure stable productivity levels and incomes. A survey of mitigation and adaptation strategies has been carried out, together with an assessment of the spatial extension of phenomena for this area, within the framework of the RIADE project on desertification. A permanent multi-parametric probe to collect conductivity data in a specific point of the Salso-Imera river has been wirelessly connected to the Agricultural Extension Service Office (SOAT) of Licata. This information is used to alert the farmers of critical situations and give them the possibility to adopt the best solution to reduce the salinity reaching their fields. Figure 16 Licata 14 Figure 17 Map of the Licata plain showing spatial distribution of electrical conductivity, ms/cm (Red colour means area with higher salinity levels)

17 FINAL CONSIDERATIONS The most recent Intergovernmental Panel on Climate Change (IPCC) scenario (Special Report on Emissions Scenario, for the next 50 years highlights the risk of temperature increase and precipitation decreasing in the Mediterranean region, two phenomena that could dramatically increase salinisation processes in the Mediterranean coastal areas. The challenges we are facing today, to provide solutions to the problems of salinisation, include: 1. the need to mobilise the scientific community to mount an integrated program for methods, standards, data bases and research networks for assessment and monitoring of soil salinisation 2. the great need for a multi-disciplinary approach 3. a better understanding of the genetic, biochemical, and physiological bases of salt tolerance 4. development of land use models that incorporate all the natural and human-induced factors that contribute to salinisation, to be used as land management tools 5. development of information systems that link environmental monitoring, accounting and impact assessment to salinisation 6. development of policies that will assist in the greater use of land resource information for sustainable agriculture 7. a requirement for greater pragmatism from national decision makers in subscribing towards a safeguard for ecological sustainability, biological diversity and economic productivity 8. development of cost-effective instruments for the assessment of salinisation, to encourage the suitable use of land resources 9. development of mitigation technologies. Indicators, such as measurements of salinisation, deterioration of soil structure, and loss of soil organic matter, can be used to provide early warning of land degradation and an assessment of land quality, within stressed environments It is, however, not enough to research and understand the problems. We have to ensure that the knowledge we have gained is applied in practical ways, for the benefit of mankind. 15 Figure 18 Alentejo Portugal

18 FURTHER READING AND REFERENCES Benavente, K. el Mabrouki, M. Himi, J.L. García-Aróstegui, C. Calabrés y A. Casas, Uso de técnicas geofísicas para caracterizar la extrusión de agua salina en un acuífero costero mediterráneo bicapa (Río Vélez, provincia de Málaga) Use of geophysical techniques to characterize the extrusion of saline water in a two-layer Mediterranean coastal aquifer (Vélez River, Málaga province). GEOGACETA, 37: Brandt J, Geeson N. Imeson A., 2003: A desertification indicator system for mediterranean Europe. EU project EEA, 1998: Europe s Environment: The second assessment. EEA, 2003: Europe s Environment: The third assessment. EEA, 2003: Europe s water: an indicator based assessment, Topic report Europe s water: an indicator based assessment, published in 2003, Source: EEA Eionet IRENA FAO UNESCO Assessment Global assessment of current water resources using total runoff integrating pathways. Publication/2001/HSJOki2001.pdf SWIMED Sustainable water management in Mediterranean coastal aquifers: recharge assessment and modelling issues. description.htm IPCC Special Report on Emissions Scenario,

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