State of Israel

 

 

First National Report

On the Implementation

Of the

United Nations

Convention to Combat Desertification

 

 

November þ2000

 

 

Prepared by

The Blaustein Institute for Desert Research

Sede Boqer Campus

Ben-Gurion University of the Negev

 

For the

 

Department of International Organization

The Ministry of Foreign Affairs

Government of Israel

 

 

 

 

 

 

 

 

 

Summary

 

This is the first report of Israel as an Affected Country Party of the UNCCD. The document is an initial, preliminary attempt to analyze and evaluate past, present and future expressions of desertification and risks of desertification in Israel, to identify problems and to propose approaches for combating desertification in Israel. Thus, this document does not attend the commitments of Israel as a Party to the CCD in assisting Developing Country Parties to combat desertification; this issue is reported in a separate document submitted to the Secretariat of the CCD for presentation in COP4.

 

Israel is dryland country, with dry subhumid, semiarid, arid and hyperarid drylands covering its area successively along a north – south and west – east descending precipitation gradients. Its dry subhumid areas are of an eastern Mediterranean eco-climatic nature; the semiarid area has a strong Asian biotic component, its arid region has a mixture of Mediterranean, Asian and African desert biota, and its hyperarid areas are of Saharo-Arabian desert conditions. In Israel, the sensitivity to desertification increases with aridity, whereas the exposure to human impact decreases with aridity.

 

The arid regions of Israel suffered natural soil erosion due to climate change during early historical times, and ancient Negev populations invested commendable terracing efforts to halt this erosion and to develop run-off agriculture there. From the dawn of history nearly all parts of the country have been under intensive land use by humans, including pastoralism and cropping, though evidence for desertification or the lack of it during historical times is not conclusive. During the turn of the 19th century and the beginning of the 20th century exploitation of woody and herbaceous vegetation especially in the dry subhumid areas, for firewood and due to grazing, caused severe soil erosion and significant degradation of vegetation. Many lowland regions have become waterlogged and salinized. It is not known whether or not semi-arid drylands suffered desertification at that time.

 

Measures to combat dry subhumid desertification (afforestation and drainage) and develop semiarid lands (water resource development) were initiated by Jewish settlers and the British Government prior to the establishment of the State of Israel in 1948. These have intensified as of the establishment of the State until today. Driven by needs to settle the country mainly through agricultural development, extensive afforestation projects apparently arrested soil erosion and promoted the rehabilitation of vegetation and restoration of water-related ecosystem services, mainly in the dry subhumid regions. Concurrently with afforestation, exploitation and grazing pressure on the dry subhumid scrublands have been significantly reduced, with a fast transition of the vegetation to woodland formation, with apparent restoration of water and soil related ecosystem services.

 

Grazing pressure in the semiarid regions was reduced as well, and many semiarid rangelands and rain-fed croplands were transformed into irrigated croplands. The sustainability of this agricultural development and its potential to avert salinization risks in the semiarid region have been driven by transportation of high-quality irrigation water from dry subhumid-generated resources. This has been augmented by water conservation measures hinged on the invention and implementation of drip irrigation and fertigation technologies, and by backing of agricultural research and assistance of agricultural extension services. Most dry subhumid areas, as well as many arid and even hyperarid areas have benefited from the agricultural experience gained in the semiarid region and the infrastructure established to support it. By the same token, afforestation practices developed for the dry subhumid areas have gradually “migrated” to semiarid and even arid regions. The discovery of geothermal, brackish fossil groundwater in the Negev and the adaptation of conventional greenhouses to growth houses (“protected agriculture”) in dry and hot regions of Israeli drylands, provided Israeli farmers with options of intensive cash-crop agriculture and recently also of aquaculture – practices that are economic on land use and hence of little if any desertification impact.

 

During its first decades, Israeli agriculture development, water resource development, water conservation policies, and afforestation projects seemed to have rehabilitated many previously desertified areas and to have prevented further desertification. However, in recent decades signs of emerging desertification and of future potential risks have been detected. In the dry subhumid areas there is soil salinization due to irrigation in dry subhumid valleys, and increasing impenetrability of dry subhumid woodland and “bush encroachment” leading to degraded range quality on the one hand, and woodland fires leading to soil erosion on the other hand. In the semiarid areas there are indications of sheet soil erosion on irrigated agricultural land, and of highly intensified galley erosion, both in regions of agricultural activity and of grazing activity. Risk of soil salinization of a large scale may become high due to expanding areas of agriculture irrigated with treated wastewater, which is not desalinated. Similar risk is imminent in arid drylands that are due for further agricultural development to be irrigated with brackish fossil water, though at a smaller scale. Galley erosion is evident also in the arid region, and risk of salinization is imminent in the intensive though patchy agriculture in the hyperarid areas. Both the arid and the hyperarid areas suffer from excessive road construction and use, leading to loss of vegetation, soil erosion and loss of water.

 

Israel has not produced a National Action Plan to Combat Desertification. In recent years it has initiated and completed a National Masterplan for the hyperarid and part of the semiarid parts of Israel, and a process of exploring, together with stakeholders and experts, the country’s options for sustainable development and modalities for synergizing the joint implementation of the “Rio Conventions.” A planning workshop carried out in 1999 within the framework of regional cooperation to combat desertification in the Middle East and utilizing a participatory approach, established a preliminary template for a National Action Plan, with emphasis on research. An intra-governmental Steering Committee on Desertification has been set to coordinate the activities of government departments related to combating desertification, and an advisory professional committee advises the Steering Committee on budget allocation. A list of urgent activities that may constitute a framework for an Israeli NAP includes actions for assessing, combating and monitoring soil salinization, sheet and galley erosion, and for improving the management of rangeland, woodland fires and road construction and use. Above all it is necessary to increase the awareness of the public and decision makers alike, to the already occurring and to the future damages of desertification. It is also critical now to evaluate the feedbacks between desertification, loss of biodiversity and predicted future impacts of climate change, and to design an effective joint implementation of the UNCCD, the CBD (Convention on Biodiversity) and the UNFCCC (Framework Convention on Climate Change), such that it paves the path for Israel towards sustainable development.

 

Table of Contents

 

Summary *

1. Introduction *

1.2 Israel is an Affected Country Party *

1.3 Obligations as an Affected Country Party *

1.4 Structure and function of the document *

2. Desertification in Israel *

2.1 The Land *

2.1.1 A country at the crossroad of Asia, the Mediterranean Basin and Africa *

2.1.2 A land of climatic gradients *

2.1.3 A dryland country *

2.1.3.1 The Dry subhumid drylands *

2.1.3.2 The Semiarid drylands *

2.1.3.3 The Arid drylands *

2.1.3.4 The Hyperarid drylands *

2.2 Desertification *

2.2.1 What is desertification? *

2.2.2 Vulnerability to desertification *

2.2.4 Desertification prior to the State of Israel *

2.2.4.1 Dry subhumid and northern semiarid drylands *

2.2.4.2 Southern semiarid and arid drylands *

2.2.4.3 Semiarid and arid water resource development *

2.2.4.4 Hyperarid drylands *

2.2.4.5 Old desertification and new development *

3. Combating desertification in Israel *

3.1 What is combating desertification? *

3.2 Measures for reducing vegetation loss and soil erosion *

3.2.1 Control of dry subhumid scrubland grazing *

3.2.2 Control of semiarid and arid grazing *

3.2.3 Afforestation as a measure for soil conservation *

3.2.3.1 Afforestation legislation and policies *

3.2.3.2 Afforestation in dry subhumid regions *

3.2.3.3 Afforestation as a measure for combating desertification *

3.2.3.4. Afforestation of semiarid drylands *

3.3 Transformation of semiarid rangeland to irrigated cropland – dryland agriculture *

3.3.1 Averting desertification risks *

3.3.2 Improving climate by measures for combating desertification *

3.3.3 Water transportation projects for semiarid irrigation *

3.4. Irrigation and salinization *

3.4.1 The risk of salinization of irrigated croplands *

3.4.2 Conserving irrigation water and preventing salinization *

3.4.3 Water policies for sustainable agricultural development *

3.5 Reducing pressure on soil resources *

3.5.1 Protected (greenhouse) agriculture *

3.5.2 Cash crop dryland agriculture and aquaculture *

3.5.3 Success and sustainability of dryland agriculture *

4. newly emerging desertification *

4.1 Is there development-induced desertification? *

4.2 Soil erosion *

4.2.1 Old and new gully erosion *

4.2.2 Indicators for soil degradation on semiarid agricultural land *

4.2.3 Galley erosion due to overgrazing *

4.2.4 Sheet erosion due to grazing *

4.2.5 Galley erosion due to road construction and use *

4.3 Soil salinization *

4.3.1 Current agriculture-related salinization *

4.3.2 Irrigation with brackish water in the hyperarid and arid regions *

4.3.3 Irrigation with treated wastewater in the semiarid region *

4.4 degradation due to reduced grazing *

4.4.1 Increased flammability, fires and soil erosion *

4.4.2 “Bush encroachment”– loss of biodiversity and forage value *

5. Implementation of the CCD by Israel *

5.1. Synergies in implementation *

5.2 Planning for promoting sustainable development *

5.3 National Planning Workshop *

5.4 National Committee *

5.5 Outlines for a NAP for Israel *

5.5.1 The dry subhumid drylands *

5.5.2 The semiarid drylands *

5.5.3 The arid drylands *

5.5.4 The hyperarid drylands *

5.5.5 NAP components common to all dryland types *

6. References *

 

 

 

1. Introduction

 

1.2 Israel is an Affected Country Party

 

Israel signed the United Nations Convention to Combat Desertification (UNCCD) on 26 March 1994 and was the 27th country (out of 169) to ratify it, on 26 March 1996. As of Entry into Force on the 26 December 1996, the State of Israel is an Affected Country Party of the UNCCD (affected country is one whose lands include, in whole or in part, affected areas; affected areas are arid, semi-arid and /or dry sub-humid areas affected or threatened by desertification, [UNCCD Article 1 “Use of Terms”]; other categories of Parties to the UNCCD are Affected Developing Country Parties and Developed Country Parties).

 

1.3 Obligations as an Affected Country Party

 

The obligation of Israel as an Affected Country Party, in addition to its obligations pertaining to all Country Parties, is to combat desertification within its territory. This includes (UNCCD Article 3):

 

 

One way of meeting these obligations is by preparing, making public and implementing a National Action Program (NAP). This option should be taken by Affected Country Parties that have notified the Secretariat of the UNCCD in writing of their intention to prepare a NAP (UNCCD Article 9[1]); To date, Israel has not made such a notification. Yet, each Party should communicate to the Conference of the Parties (COP), through the Secretariat of the Convention, reports on measures that it has taken for the implementation of the Convention (UNCCD Article 26). This communication serves for regular reviewing of the implementation of the UNCCD and for exchanging information between the Parties, on measures to combat desertification adopted by each of them (UNCCD Article 22).

1.4 Structure and function of the document

 

Pursuant to Decision 11 taken during the first COP [ICCD/COP (1)/11/Add.1, pp.41-46], Israel hereby communicates to the Secretariat its first Report, as an Affected Country Party not preparing an Action Program; this communication includes, as required by the above decision [Annex I of ICCD/COP (3)/INF.3], a discussion of “the strategies and priorities, within the framework of sustainable development plans and/or policies, to combat desertification and mitigate the effects of drought, and any relevant information on their implementation.” Thus, the purpose of this report is to inform the Parties to the Convention on the situation in Israel with regard to measures taken for the implementation of the UNCCD at the national level.

 

As proposed by the UNCCD National Reports Help Guide [ICCD/COP (3)/INF.3], “The formulation of national reports is part of the process of implementing the Convention… the reports should help to strengthen the institutional and human capacities … to improve their ability to coordinate and motivate the further steps required for the effective implementation of the UNCCD …”. Indeed, this document aims at raising the awareness of policy-makers, decision-makers, governmental and non-governmental organization and the general public of Israel, to the manifestation of desertification in Israel and the need to address it. This report, therefore, may catalyze preparation of an Israeli NAP. Being the first Israeli attempt to report to the UNCCD, this document constitutes only a platform for the construction of a subsequent participatory and integrated comprehensive report.

 

2. Desertification in Israel

 

2.1 The Land

 

2.1.1 A country at the crossroad of Asia, the Mediterranean Basin and Africa

 

Israel is a north-south oriented (470 km long and 135 km wide across its widest point) Asian-Mediterranean country, geographically located at a crossroad of three UNCCD Regions - the Northern-Mediterranean, the Asian and the African regions (to each of which the UNCCD has a specific Implementation Annex). An extension of the Asian steppes east of Israel is wedged between the northern section of Israel (which is part of the northeastern Mediterranean eco-climatic region), and the southern section of Israel (which is an extension of the African [Saharan]-Arabian deserts). Thus, within the small area of Israel (22,145 km2) the ecological peripheries of the Mediterranean scrubs, the Asian steppes and the African deserts - meet.

 

2.1.2 A land of climatic gradients

 

The climatic feature common to all three biogeographical sectors of Israel is a short, cool rainy winter, and a long, hot dry summer. However, though of a very small size (22,145 km2) the unique geographical disposition of Israel induces a rich climatic diversity. Gradually but steeply rainfall decreases (700-30 mm) and potential evapotranspiration increases (1200-2800 mm) from north to south, as well as with reduced elevation. A west-east ecoclimatic gradient is superimposed on an elevation gradient of 1200 m above sea level (at the highest points along the north-south oriented highland range extending through the whole length of Israel) to 400 m below sea level (the lowest point along the Jordan-Arava Rift Valley, bounding the highland range from east). West of the water divide, from the highland peaks to the Mediterranean coastal plain a less pronounced but significant ecoclimatic gradient is evident too. On top of these gradients in climatic means, a north -south and higher-lower elevation gradients exist in climatic variability around these means, namely – an increasing variability and uncertainty in precipitation with increasing aridity.

2.1.3 A dryland country

 

The long, hot and dry summer that extends all over Israel, and the spatially prevailing ranges of precipitation and potential evapotranspiration make Israel a dryland country.

Adopting UNEP’s classification of the global drylands by assigning the Aridity Index, based on the precipitation/potential evapotranspiration ratio (Middleton & Thomas 1997), and using long-term climatic data of Israel (New Atlas of Israel 1995), the four UNEP’s categories of global drylands can be superimposed on the ecoclimatic gradients of Israel, as follows:

 

2.1.3.1 The Dry subhumid drylands

 

Lands with Aridity index lower than 0.65 (potential evapotranspiration is above ca one and a half times higher than precipitation) are drylands. The least dry category of drylands, the Dry subhumid one, can have evapotranspiration twice higher than precipitation, namely – the Aridity Index of this category ranges between 0.50 to <0.65. In Israel the Dry subhumid areas extend north of Ashdod on the coastal plain and north of the Hebron western foothills on the Judea and Samaria western foothills, and include most of the coastal plain, the northern valleys and the Galilee. Mean annual precipitation in these areas is 500-750 mm, and the mean annual evapotranspiration can go lower than 1400 mm. The dry sub-humid region is of a typical eastern-Mediterranean climate and is inhabited by eastern Mediterranean natural communities of plants and animals. Open areas have indigenous woodlands and scrublands, planted forests, and orchards. Urbanization, industry and population are greater in the southern parts of the Dry subhumid area (230 persons/km2 and 1065/km2 in rural areas in the north and the south, respectively, and 914/km2 and 6660/km2 in urban areas, respectively; for 1998 [Central Bureau of Statistics 1999]).

 

2.1.3.2 The Semiarid drylands

 

Semiarid drylands are those with Aridity Index ranging between 0.20 and <0.50. Semiarid drylands of Israel are located south and east of the dry subhumid drylands, south to Kisoufim on the coastal plain, to Bet-Kama junction in the center and east to Arad on the central mountain range, then down to half way between the Judean and Samaritan mountains’ water divide and the Dead Sea basin and the Jordan valley, respectively. Thus, the northern Negev, the upper reaches of the Judean Desert, the northern Jordan Valley, the Kinnarot and the Hula Valleys, are semiarid drylands. TMean annual precipitation is 300-500 mm, and the mean annual evapotranspiration may range between 1500 to 1700 mm. The Semiarid region is of a typical Asian (“Irano-Turanian”) biota, mixed with both Mediterranean and Sahara-Arabian desert elements. Most open areas are used for irrigated agriculture, with very few areas protected for the conservation of low scrub or grassland biodiversity. Population density ranges 100-500 persons/km2.

2.1.3.3 The Arid drylands

 

Arid drylands are those with Aridity Index ranging between 0.05 and <0.20. Arid drylands of Israel are located south and east of the semiarid drylands, south to Sede Boqer in the southern central highlands, and east to the lower reaches of the Jordan Valley. Thus, the western Negev and Be’er-Sheva Valley, the central reaches of the Judean Desert and the southern Jordan Valley are semiarid drylands. The Mean annual precipitation is 100-300 mm, and the mean annual evapotranspiration may range between 1700 to 1800 mm. The arid region is of a typical Saharo-Arabian desert biota, mixed with Asian and Mediterranean elements, especially in its northern and higher-elevation sections. Within the arid region noteworthy are the inter-annual spatial fluctuations of the 200 mm isohyete, one that is of much significance to the viability of rain-fed cereal cropping. Most open areas are used for irrigated and rain-fed agriculture, with many areas used as Bedouin rangeland, and very few areas protected for the conservation of biodiversity rich in peripheral populations. Population density ranges 35-60 persons/km2.

 

2.1.3.4 The Hyperarid drylands

 

Hyperarid drylands are those with Aridity Index lower than 0.05. They are regarded as true deserts, hence offering very limited opportunities for human activities. Accordingly, hyperarid drylands are not regarded by the UNCCD as at risk of being further decertified, and hence are not covered by the UNCCD. Hyperarid drylands of Israel are located south and east of the arid drylands. They include the central and southern Negev from Mitzpe Ramon to Elat, the Dead Sea Basin and the Arava Valley. The Mean annual precipitation is 30-90 mm, and the mean annual evapotranspiration may range between 1800 to 2800 mm. The hyperarid region is of a typical Saharo-Arabian desert, with an acacia savanna in the Arava Valley. Agricultural development, all irrigated and much of it protected in greenhouses, is restricted to oasis type patches depending on local, often fossil groundwater resources. Much of the land is used as nature reserves and military maneuvering areas. Population density is much less than 100/km2, and the only city is Elat, on the head of the Gulf of Aqaba/Elat.

 

To conclude, except for a few high-elevation areas in northern Israel that could be regarded as humid, nearly all Israel is a dryland; being located at the edge of three dry climatic regions, all types of global drylands are represented in Israel.

 

2.2 Desertification

 

2.2.1 What is desertification?

 

All deserts, the Negev and the Judean deserts of Israel included, are areas that have, at some time during their geological history, undergone a process of becoming deserts, namely – desertification. The UNCCD, however, defines desertification (Article 1) as “land degradation in arid, semiarid and dry subhumid areas resulting from various factors, including climatic variations and human activities”. Land degradation is “reduction or loss, in arid, semiarid and dry subhumid areas, of the biological or economic productivity and complexity of –

 

resulting from land uses and processes … arising from human activities and habitation patterns such as –

 

 

“Land” is defined by the UNCCD too, as “terrestrial bio-productive system that comprises –

 

 

Thus, desertification in the context of the UNCCD and this national report is basically a human-induced phenomenon in drylands (except in the most extreme type of desert, the hyperarid dryland, that is not expected to become further desertified by humans), a phenomenon engaging the soil, which is viewed as an ecological-hydrological system that provides services to humankind. The issue at stake is therefore – are the Israeli drylands affected by desertification, as defined by the UNCCD?

 

2.2.2 Vulnerability to desertification

 

Adopting Climate Change related terminology regarding exposure, sensitivity, adaptability, vulnerability and impact (Watson et al. 1996) for use in the desertification context, exposure will refer to human activities of a desertification-inducing potential, sensitivity will be the degree to which a specific dryland is affected by the exposure, adaptability will be the capacity to adapt human activity and dryland to prevent desertification, and the impact is the overall reaction of a dryland to human activities. In general, the sensitivity of drylands increases with their aridity. However, Israel’s development initiated at the center of the dry subhumid region, and was gradually extended to drylands of increasing aridity. Hence the exposure of Israeli drylands diminished with their aridity. Furthermore, as time advanced since the Jewish colonization of the Land of Israel started at the turn of the 19th century, not only development efforts spread into more and more arid areas, but also experience accumulated, namely – adaptability increased. Thus, since the most sensitive drylands (the arid drylands) have been least exposed to desertification agents, and when exposed adaptability was relatively high, altogether Israeli dryland have been and are of low vulnerability to desertification.

 

2.2.4 Desertification prior to the State of Israel

 

2.2.4.1 Dry subhumid and northern semiarid drylands

 

It was claimed that Mediterranean vegetation, for example, has co-evolved with Mediterranean soils in reaction to grazing, fire and other anthropogenically-induced impacts (Naveh 1987). Indeed, humans for millennia have intensively utilized the dry subhumid and at least part of the semiarid parts of current Israel. Travelers to the region during the last decades of the 19th century encountered many woodlands but also others that turned into scrublands due to exploitation. Much intensified utilization occurred at the turn of the 19th century and at the first two decades of the 20th century. Thus, a 1920 survey yielded only 600 km2 of indigenous woodland and scrubland in the dry subhumid regions between of present Israel and the West Bank (ISRAEL MASTER PLAN 22 1993). Most of the dry subhumid mountainous area was thus with degraded woody vegetation or completely deforested, with rocky surfaces exposed due to soil erosion, whereas some big valleys were waterlogged and swamped. Thus, the dry subhumid and at least the northern parts of the semiarid parts of Israel seem to have been desertified. By 1948, the year of the establishment of the State of Israel, most of the marshes were drained and their lands cultivated, many of the barren slopes (some 80 km2, ISRAEL MASTER PLAN 22 1993) were afforested, and irrigated agriculture and orchard abounded, especially on plains and in valleys.

 

2.2.4.2 Southern semiarid and arid drylands

 

It is not clear whether or not the southern semiarid and the arid drylands have been desertified by the turn of the 19th century. Empirical studies of traditional pastoralism indicated that livestock populations maintain non-equilibrium but persistent state and the rangelands they used seemed to be stable at a low equilibrium state (Seligman and Pervolotsky 1994, Pervolotsky and Seligman 1995). There is much evidence that livestock grazing does not necessarily reduce Israeli dryland vegetation to the point of non-sustainability of the range, or impair the maintenance of plant biodiversity. Furthermore, grazing has been experimentally shown to promote plant biodiversity of Israeli rangelands, and not necessarbe the major determinant of soil productivity (Pervolotsky 1999). However, the effect of grazing on soil erosion and degradation in the drylands of Israel has not received attention, and remains unknown.

 

Until 1948 mainly nomadic Bedouin tribes inhabited the semiarid and arid lands. The Bedouin - who numbered some 65,000 to 103,000 at that time (Abu-Rabia 1994) and were spread out over an area of about 10,000 km2 - subsisted principally on sheep, goat and camel herding. But already as of the middle of the 19th century Bedouins initiated patchwork farming in wadis that had previously been used exclusively as rangeland, and also raised cereals through dry farming, often as a cash crop (Kressel et al 1991). In rainy years they also cropped in late winter and spring 2500 km2, reduced to 600 km2 in low rainfall years (Porat 1996). Thus, being dependent on erratic seasonal rains and floods, they were often short of food for themselves and for their flocks. In the semiarid drylands the Bedouins practiced subsistence rain-fed agriculture of cereals, restricted to winter and early spring crops that frequently failed. In some arid regions localized farming was based on the stone dams constructed in channels during historical period probably ending in the 6th century. The ancient dams, supplemented by the Bedouins by simple barriers made of dirt, were used to prevent soil carried by floods from being lost to the Mediterranean Sea, to create agricultural terraces, and to enable floodwater to infiltrate and be stored in these soils. These wadi terraces have been used for fruit trees and vegetables. No study has been carried out to determine whether or not the Bedouins used the rangelands sustainably; and since their agriculture was non-irrigated one, it may be assumed that it did not cause significant salinization.

 

2.2.4.3 Semiarid and arid water resource development

 

By 1948 there were 20 Jewish agricultural settlements in the arid areas, mostly engaged in agricultural experimentation. The experience these settlers brought with them was gained somewhat earlier, by farming in the already desertified dry subhumid parts of the country, as well as in the some of the semiarid areas. Most of the Jewish farmers that have been engaged in the initial, pre-State attempts of farming the country’s drylands, originated from non-dryland countries and had no farming experience or tradition. These facts might have facilitated their fast recognition that economically viable agriculture of drylands hinged on irrigation, which in turn is constrained by the scarcity of water and the uncertainty of its supply. This recognition led to the launching of meteorological, geological and hydrological surveys. These resulted in attempts to drill wells and draw underground water; however, the quantities obtained were quite small, and the salinity of the water was often too high for agricultural use. Attempts to build dams and reservoirs to collect seasonal floodwaters failed because of the large inter-annual climatic fluctuations, as well as technical difficulties. Eventually it was concluded that the only way of securing a dependable and sufficient supply of water for agriculture was to subsidize the arid (and some semiarid) regions by transporting fresh water from sources in the dry subhumid region, via pipes. The first pipeline installed in 1947 was modest (6’’ diameter, 190 km long, providing 1 million m3 annually), but it firmly implanted the concept of driving dryland agricultural development by transported water (Sitton 1997).

2.2.4.4 Hyperarid drylands

 

The hyperarid areas have been sparsely inhabited by Bedouin pastoralists that have often used them at certain periods determined by their migration patterns. It is very unlikely that hyperarid areas have been then overgrazed. Development was introduced to these areas only after the establishment of the State of Israel. Thus, it is safe to assume that the hyperarid region has not been further desertified by human activity prior to the establishment of the State of Israel.

 

2.2.4.5 Old desertification and new development

 

A unifying working hypothesis regarding desertification prior to the establishment of the State of Israel is that until the end of the 19th century the country was desertified, but the impact diminished with aridity. The expression of desertification might have been soil salinization in dry subhumid areas, and definite loss of natural vegetation and soil erosion in dry subhumid and some semiarid areas. In both dryland types ecological and hydrological processes would have been disrupted, the provision of ecosystem services have been impaired, resulting in an overall gradual decline in productivity. On the other hand, it is likely that local populations used the arid regions sustainably with no recognizable impact of desertification. Finally, the hyperarid regions have not been impacted. A steadily increasing influx of Jewish immigrants at the turn of the 19th century brought about an introduction of agricultural development, mainly driven by water resource development, with potential impact decreasing with aridity. These activities intensified as of the establishment of the State of Israel in 1948, and it is now necessary to evaluate this development in the context of combating desertification.

3. Combating desertification in Israel

3.1 What is combating desertification?

 

Combating desertification is defined in the UNCCD (Article 1) as “… activities which are part of the integrated development of land in arid, semiarid and dry subhumid areas for sustainable development which are aimed at:

 

 

Thus, combating desertification means (a) preventing non-desertified lands from becoming desertified, and (b) rehabilitating already desertified lands. Since desertification is caused by development, then prevention means development that does not cause desertification, namely - sustainable development of drylands. Furthermore, through development that is sustainable, already desertified drylands can be rehabilitated. It is now necessary to evaluate whether the intensified development of Israel as of its establishment, has been sustainable, to the extent that it prevented desertification and brought about rehabilitation of desertified drylands.

3.2 Measures for reducing vegetation loss and soil erosion

 

3.2.1 Control of dry subhumid scrubland grazing

 

To reduce overgrazing in the dry subhumid areas, mainly by goats feeding on scrubland major tree species, The “Black Goat Low” [The Low for Vegetation Protection (Goat Damages)] was enacted in 1950. Prior to 1948 the number of goats is estimated at 185,000. Demographic and socio-economic trends in these areas dramatically reduced this number to 71,000 in 1950, and with it - the pressure on the natural scrubland was dramatically reduced and it rapidly developed into typical eastern Mediterranean woodlands. Though later the numbers increased to 115,000 (1973), went down to 70,000 (1994) and then again increased to 74,000 in 1998 (Central Bureau of Statistics 1999), the overall positive effects of the reduced grazing pressure demonstrates the high resilience of the dry subhumid Mediterranean woodland ecosystems, attributed to the long co-evolution of these systems with human-induced disturbances, grazing included (Pervolotzky & Zeligmann 1993, Pervolotsky 1995). The effect of this rehabilitation of vegetation covers on soil erosion and on ecological and hydrological processes related to local and regional productivity is not known, though it is evident that removal of such woodlands dramatically increases runoff and soil erosion (Inbar et al 1998).

 

3.2.2 Control of semiarid and arid grazing

 

As of 1948 the number of Bedouins in the Negev dropped, probably from 70,000 to 11,000-12,000 persons (Kressel et al 1991, Abu-Rabia 1994). The pressure of livestock on the vegetation of these areas then considerably decreased due to the reduced number of Bedouins and other socio-economic changes, including land privatization, farming and the cabandonment of the nomad lifestyle. It is not know, though, what was the precise size of the Bedouin herd prior to 1948 and immediately afterwards. This is due to the fact that prior to 1948 Bedouin nomadism was not constrained by borders, as well as to lack of reliable statistics (one estimate is 70,000 sheep and 14,000 camels in 1943, Abu-Rabia 1994). It can be asserted, though, that at least during the first decade as of the establishment of the State the pressure of livestock on the semiarid and arid regions considerably declined.

 

3.2.3 Afforestation as a measure for soil conservation

 

3.2.3.1 Afforestation legislation and policies

 

The Jewish National Fund (JNF, better known in its Hebrew acronym KKL), a national non-governmental organization, was contracted in 1961by the Government of Israel to carry out all necessary afforestation activities in Israel. Between 1948 and 1993 the KKL has planted over 200 million trees (around two-thirds of which are Aleppo pines) divided between 280 afforestation plots and jointly covering 690 km2 (ISRAEL MASTER PLAN 22, 1993) in 1993 and 911 km2 in 1999 (Central Bureau of Statistics 1996-1999).

 

All afforestation areas in Israel fall under legislation (“Forest Law”, City Building Directive”, “National Parks and Nature Reserves Law”). The 22nd Country Master Plan is the National Masterplan for Forests and Afforestation for the coming 25 years, as of November 1995, the time of its legal approval. The Masterplan determines the function, the legal status and the management practices of existing and future indigenous, afforested and managed woodlands in Israel, to amount to 1606 km2 (7% of Israel and over 15% of the dry subhumid and semiarid regions of Israel). During coming years additional 360 km2 are designated for afforestation, 115 of which in the semiarid region (ISRAEL MASTER PLAN 22, 1993). The Afforestation Division of the KKL has instituted a watchdog system for identifying development plans that are incompatible with the Masterplan, so that timely counter measures can be taken.

 

3.2.3.2 Afforestation in dry subhumid regions

 

Afforestation is a practice for rehabilitation of lands already affected by soil erosion, as well as for preventing soil erosion. Most afforestation projects have been carried out at first in the dry subhumid regions of Israel, and later also in some semiarid regions. The commonest afforestation species has been the Aleppo pine Pinus halepensis, a circum-Mediterranean species, with isolated indigenous populations in Israel restricted to mountainous dry subhumid regions and specific rock and soil types. This restricted distribution may be due to the species’ life-history strategy that is typical to pioneering species, fast to colonize after disturbances but with low competitive ability. This species has been widely used, on landscape, rock and soil types not covered by this indigenous distribution, and often with exotic seed sources. The major assets of this species are the fast growth and the high survivorship under diverse ecological conditions. The disadvantages are the relatively low longevity, the low resistance to certain parasites, and the high flammability. In recent years the KKL has significantly diversified the species composition of its afforestation trees, reduced the number of exotic species in favor of common indigenous Israeli species.

3.2.3.3 Afforestation as a measure for combating desertification

 

It would be instructive to determine the relative allocation of afforestation efforts to lands of different degrees of soil erosion, and more importantly, to evaluate the effects of the Israeli afforestation projects on soil erosion, with respect to the initial state of the soil, the type of dryland and the type of tree species used. Besides directly contributing to soil conservation, plots used for afforestation have deterred pastoralists, thus afforestation has reduced grazing pressure too. This reduced grazing and the shading effect of the trees promoted in many places rehabilitation of the indigenous vegetation, what further contributed to soil conservation. Afforestation is also expected to improve the infiltration of precipitation, thus promoting soil moisture and aquifer recharge. However, it was found (Stanhill 1993) that the Israeli dry subhumid indigenous woodlands transpire more soil water than the dry subhumid agricultural lands. Therefore, the role of Israeli afforestation in the hydrological cycle should be carefully evaluated. Finally, afforestation has been used in Israel for preventing gully erosion and bank erosion through planting along creeks, for stabilizing sand dunes, for reducing impacts of wind and dust, and especially in recent years, for recreation and leisure activities.

 

3.2.3.4. Afforestation of semiarid drylands

 

Since the 1950s a chain of forests was created in the semiarid areas, using conventional afforestation techniques As of 1964 intensified afforestation efforts have been directed towards the semiarid region. The Yatir forest covering 30 km2 of 250-300 mm annual rainfall, is probably at the most arid periphery of the global distribution of the Aleppo pine, and is regarded as a remarkable success of afforestation at an area of high desertification exposure and vulnerability. Yet, the two successive years of drought (1998-2000) resulted in massive mortality in many plots in the semiarid region.

 

As of 1986 an afforestation practice, locally called “Savannization”, adapted for semi-arid and even arid regions, has been experimented with. This is an afforestation practice based on harvesting of surface run-off, through whole watershed management in semiarid regions, even some bordering with the arid region, within a precipitation range of 150-250 mm. Contour furrows are dug on slopes of Watersheds with sandy-loessial soils with several tens of meters of vertical distance between them. The space between furrows that is covered by a biogenic soil crust that reduces infiltration generates surface run-off that is collected, infiltrate and is stored in the furrows, in which trees are planted at a density of ca 100/hecatre. During a rainy season 4-6 rainstorms produce surface run-off on the plots, which add to the trees in the furrows 6-37% of total annual precipitation, at a storage depth that is fairly well protected from evaporation. Controlled experiments demonstrated reasonable growth and survival of the trees, increase productivity of pasture, and increased plant biodiversity (KKL 1994). By 1999 23 km2 have been successfully “savannized” (Sachs & Moshe 1999), and the Masterplan designs additional semiarid areas for this type of semiarid afforestation. Though the direct effect of “Savannization” on soil erosion and of other semiarid afforestation practices on the water cycle (Adar et al 1995) has not been fully determined, it is evident that “Savannization” reduces flash floods and their consequent soil erosion, and increases the overall productivity of semiarid soils. The survivorship in drought years, of trees watered by surface run-of under this practice, may be much better than that of trees planted in semiarid areas but depend just on rainfall.

3.3 Transformation of semiarid rangeland to irrigated cropland – dryland agriculture

 

3.3.1 Averting desertification risks

 

As noted in Section 3.2.2 grazing has been considerably reduced in the semiarid regions. Most of the rangelands relieved from grazing pressure have been transformed into irrigated croplands, or to croplands that are rain-fed in winter and irrigated in summer. Transformation of rangeland to cropland is one of the drivers of desertification, since this encompasses total removal of the rangeland vegetation cover and breakage of the biogenic crust through plowing. When the land is not tilled during the non-rainy season wind erosion is imminent, and first winter rains can generate physical crust with a consequent intensified run-off and water erosion. However, most of these rangelands transformed into cropland in the semiarid region were not rain-fed but irrigated, so that the agricultural practices rarely leave the soil uncovered for a long period.Furthermore, since fields were irrigated with transported water of only marginal dependence on local meager, low-quality resources, enough water could be used for leaching. Therefore, soil salinization, linked to irrigation in drylands, did not occur. Furthermore, practices have been applied to increase infiltration, thus reducing surface run-off and soil erosion on agricultural fields (e.g. mulching, ridges and dyked furrows tillage, and the application of chemicals which increase infiltration rate, Agassi et al 1996). Thus, at least initially, the transformation of the rangeland to cropland was not associated with intensified desertification. On the contrary – irrigated agriculture of the semiarid region not only averted desertification risks but might have also ameliorated local climate.

 

3.3.2 Improving climate by measures for combating desertification

 

Desertification in the CCD context is a reduction in dryland productivity mainly due to human impact, not to climate change. Hence, combating desertification is preventing this reduction in productivity or restoring productivity. Natural climate change may either cause “natural” desertification, or “roll the desert back” when rainfall increases and/or evapotranspiration reduces. However, there are claims that the measures taken to combat desertification in the Israeli semiarid region ameliorated local climate and therefore constitute one of the few cases of “rolling the desert back” by means of combating desertification, and not due to natural climate change. The evidence for that is a detected increase in overall precipitation in Israel’s semiarid southern coastline and northern Negev (Otterman et al. 1990, Sharon and Angert 1998). This is attributed to the afforestation, the intensive agriculture under irrigation, and grazing restrictions that jointly reduced surface albedo and increased convection during daytime, thus enhancing diurnal rains (Otterman et al. 1990). Though a mathematical model for this area supports this theory (Perlin and Alpert 2000), the degree of amelioration and the mechanisms leading to it require more study (Steinberger and Gazit-Yaari 1996).

3.3.3 Water transportation projects for semiarid irrigation

 

Transforming rangeland and rain-fed cropland to irrigated croplands on a large scale required the planning and execution of water transportation projects. The first large-scale project was 66" diameter pipeline drawing water from the Yarkon River in the center of Israel to the Negev over a distance of 130 km. The annual output of this line was about 100 million m3 of water. The second large-scale project was the National Water Carrier completed by 1964. The carrier is a combination of underground pipelines, open canals, interim reservoirs and tunnels supplying about 400 million m3 annually. Water from the Lake Kinneret (Sea of Galilee) in the north of Israel, located about 220 m below sea level, is pumped to an elevation of about 152 m above sea level. From this height the water flows by gravitation to the coastal region, whence it is pumped to the Negev. The National Water Carrier functions not only as the main supplier of water, but also as an outlet for surplus water from the north in winter and early spring and a source of recharge to the underground aquifers in the coastal region (Sitton 1997). Though motivated mainly by the need to develop the semiarid region of Israel, these water transportation projects, together with other projects for the exploitation of groundwater (wells) and of flash-floods (dams and reservoirs - 115 with total capacity of 100 million m3 were constructed in the last decade, KKL 1996-1999), were used for the development of irrigated agriculture in the dry subhumid regions too.

 

3.4. Irrigation and salinization

 

3.4.1 The risk of salinization of irrigated croplands

 

Irrigation in drylands is the major source of soil salinization. This is because (a) dryland groundwater or surface water are relatively saline; (b) the high rates of evapotranspiration create high water demand by the crops and a consequent high quantities of irrigation water and its salinity; (c) the high evapotranspiration also causes the accumulation of salts close the soil surface and around the root zones of the crop plants, since irrigation water evaporate before managing to infiltrate to greater depths; (d) water scarcity discourages the use of much water required to leach the salts, and at the same time an excessive amounts of water can cause poor aeration of the root system or wasteful percolation through the soil beyond the volume of the root system, or both; and (e) under irrigation, productivity becomes limited by nutrients rather than by water, which requires heavy fertilization – an additional sources of salts. The risk of salinization in the Israeli irrigated croplands has been reduced by using water transported from sources of lower salinity compared to many sources of dryland water. Yet, even with transported water, water has been and remains scarce. Water conservation and its efficient use is therefore the key to both increasing productivity and at the same time averting salinization risks.

 

3.4.2 Conserving irrigation water and preventing salinization

 

Prior to 1948 crops were irrigated by surface (flood and furrow) irrigation, which is possible only when the ground is leveled and the soil type enables slow or moderate percolation of the water. In drylands surface irrigation lead to severe loss of water by evaporation and to percolation beyond the developed root system, especially in the stages of germination and early development; moreover, between irrigation sessions the plants are exposed to stress and salinity would accumulate. Pressurized irrigation with sprinklers, introduced in the early years of the State contributed much to modernizing agriculture and increasing water use efficiency. However, the most important development for making irrigated croplands sustainable has been the introduction of drip irrigation. Drip irrigation was developed in Israel and introduced into Israeli agriculture in the early 1970s. Since then it has been disseminated all over the world drylands with great success. The attributes of drip irrigation are (Sitton 1997):

 

 

Water use efficiency, which is the ratio between the amount of water taken up by the plant and the total amount of water applied, is about 45% in surface irrigation and 75% in sprinkler irrigation, in drip irriit is about 95%. Outdoor computers that control drip irrigation and fertigation further improve water use efficiency. Thus, the high water use efficiency of drip irrigation, linked to its potential to reduce the risks of soil salinization enabled the transformation of much of Israel’s lands of agricultural potential from rangeland or rain-fed cropland to year-round irrigated fields and orchards. Thus, soils maintained plant cover (crop plants rather than natural and range vegetation) and have been protected from both erosion and salinization. However, irrigated agriculture, even one based on drip irrigation and hence very prudent in water use, still depends on water supply, which is always scarce in a dryland country. The sustainability of dryland agriculture in Israel and its relative success in preventing desertification are hinged on water policies.

 

3.4.3 Water policies for sustainable agricultural development

 

In 1959 a comprehensive Water Law was enacted by the State. The Water Law makes all sources of water in the country public property, subject to the control of the state and dedicated to the needs of its inhabitants and the development of the country. Three central institutions created by the Law - the water council, the water commission and the court for water matters - are charged with carrying out a comprehensive and balanced policy of water production and supply at the national level (Sitton 1977). About 90% of the fresh water resources of Israel have been incorporated into a single system that enables implementation of a uniform national policy of water production and regular supply to the different sectors of consumers (agriculture, domestic and industry). Water quotas and water pricing are the major policy instruments. Each sector (domestic, industrial and agricultural sectors) is assigned an annual quota of water. The policy of allocation depends on the country’s water balance, which may vary between years. Sliding price scales varying according to sector have been instituted. The individual consumer, be he farmer or city dweller, pays a higher price for water consumed beyond the allocated quantity.

 

3.5 Reducing pressure on soil resources

 

3.5.1 Protected (greenhouse) agriculture

 

The development of drip irrigation reduced the risks of soil salinization and enabled large dryland areas to become cultivated yet not causing desertification. At the same time, drip irrigation was one of the factors that motivated the development of protected agriculture, which minimized the risks of desertification by altogether reducing the pressure on soil resources and even detaching much agricultural activity from the soil. Protected agriculture is based on “growth houses” or greenhouses. In a dryland greenhouse evapotranspiration is minimized, but cooling in summers and in some drylands warming in winter nights, are required. Technologies related to protected agriculture in Israel include the synthetic fabrics, cooling and warming devices and mechanisms, drip irrigation and fertigation, growth substrates, and supplies of insect pollinators. Either fully-closed chambers or partly opened at prescribed seasons and times of day, dryland greenhouses can be fertilized with CO2 and protected from insects, thus reducing the use of pesticides. Agricultural production in drylands greenhouses is very intensive, and with very high water- and soil/space-use efficiencies. Protected agriculture technologies have been instrumental in the success of agriculture even in the hyperarid parts of Israel. Thus, by turning to greenhouse dryland agriculture, much pressure on soil resources of Israel has been averted; hence this technology can be regarded as one that is instrumental in combating desertification.

 

3.5.2 Cash crop dryland agriculture and aquaculture

 

Irrigation and protected agriculture technologies that are so instrumental in combating desertification require high financial investment on the part of the farmer. The farmer therefore has to generate high profits too. Israeli dryland agriculture has therefore evolved into one that specializes on crops that fetch high prices, mainly on foreign markets. Israeli farmers assisted by the State, developed efficient transportation and marketing infrastructure for exporting their high-price agricultural products that include high quality fruits, vegetables, and ornamental plants. Sustainability of such agriculture requires constant diversification and investments in research and extension services. The diversification is necessary for standing competition, an advanced research is a pre-requisite to this diversification, and the extension service guarantees effective dissemination and implementation of the new practices and technologies.

 

Some of the cash crops bred for salt-tolerance, especially tomatoes, melons and may be also grapes, are of higher quality (sweeter and firmer fruit) when irrigated by brackish, rather than by low-salinity water. Their improved quality and out-of-season availability makes them ideal for export. Hydro-geological surveys have revealed that the Negev and the Arava valley possess considerable reserves, mostly fossil, of saline underground water with a variable concentration of salts. If this water with salinity of up to 7-8 dS/m is used with drip delivery systems and the crops are cultivated in soil-less medium or light soils, risks of soil salinization are minimized and the plants seem not only to tolerate this salinity but also to yield high quality crops.

 

Furthermore, this brackish fossil water can be used for aquaculture since for many aquatic organisms brackish water are advantageous. Fish and crustaceans, as well as unicellular algae of commercial value are profitably grown in brackish (and warm) water in the arid and hyperarid parts of Israel. Currently the fish and crustaceans are mainly for local consumption and alga and their products – for export. Aquaculture in drylands is advantageous on non-dryland aquaculture on account of the high levels of solar radiation required by the algae, and on account of the warm winters and warm water temperature required by the fish and the crustaceans. The lower expenditure thus enables farmers to be competitive on both local and foreign markets. The two types of aquaculture make use of local brackish water resources in a way that has no soil salinization risk. Furthermore, as compared to agriculture, aquaculture hardly uses soil. Like cash crop agriculture, aquaculture requires investments and marketing, but it too can be regarded as a dryland livelihood that averts the risk of desertification.

3.5.3 Success and sustainability of dryland agriculture

 

Besides irrigation technologies, Israeli dryland agriculture benefits from advances in mulching practices using plant residues, in reducing run-off and improving percolation through mechanical and chemical methods, and in plant breeding. Though most of Israeli agriculture can be viewed as dryland agriculture it manages to produce 95% of Israel’s food requirements (6 million people on 24,000 km2), most of the other 5% being imported cereals, oilseeds, meet, coffee, cocoa and sugar. This import is more than offset by agricultural export (comprising 3.6% of overall Israeli export, Central Bureau of Statistics 1996-1999). Furthermore, whereas drylands similar to those of Israel are expected to double their agricultural input by the end of 25 years since their initial development, Israeli agricultural production increased 12-fold during such a period. During the last 18 years water input to the Israeli irrigated agriculture remained static or even decreased, while productivity went up by 2.9 times (Pohoryles 1999). The question is whether this highly intensified and currently successful agricultural development is sustainable and is due to last, or it exposes the land to desertification impacts, to become detectable in the future.

 

Some 30 years ago the amount of land and water used by Israeli agriculture contributed to around 50% of productivity. But during the last decade land and water contributed to only 4% of productivity, and 96% of it can be attributed to agrotechnolo, research, extension, and mechanization, etc (Pohoryles 1999). Thus, it is possible that the high productivity is not exhausting natural resources and therefore need not lead to desertification and non-sustainability. This would then attest to the success of Israel in increasing the natural productivity of drylands by dryland agricultural development that has not, so far, caused desertification and losses in soil productivity. It should be noted, though, that only 3.7% of Israel’s labor force is employed in agriculture, which comprises only 2.5% of GDP. Thus, in-spite of it success, the relatively low contribution of agriculture to Israeli economy may lead not to soil degradation but to abandonment of agricultural land. This land may then either be designated for urban development, or for ecosystem and biodiversity conservation. The inappropriate allocation of land to these two rather incompatible uses may increase the risk of desertification, through loss of ecosystem services, especially those related to the hydrological cycle and water supplies (NRC 1999).

 

4. newly emerging desertification

 

4.1 Is there development-induced desertification?

 

The previous section describes how the desertification that developed during the turn of the 19th century and at the first decade of the 20th century has been combated in the pre-State years, and as of the establishment of the State. Not only desertified areas seem to have been rehabilitated, but also new development did not seem to cause desertification in the first decades of the existence of the State of Israel. The issue of whether or not changes in land use and the accelerated development during the first five decades of Israel not only rehabilitated previously caused desertification and averted potential risk of desertification, but also induced new desertification risks, has not received sufficient attention, neither of experts nor of policy-makers. Some people claim that there is no evidence for ongoing desertification, while others point at expression of desertification and of increasing potential risks. It has been already pointed out that indicators of desertification may easily go unnoticed or unheeded (Heathcore, 1980).

4.2 Soil erosion

4.2.1 Old and new gully erosion

 

Currently active gully erosion is easily evident in many sites in the semi-arid and arid areas of Israel. Mechanical and afforestation efforts by the KKL are directed to slow down this phenomenon in several sites. However, this phenomenon in itself is not an indication of anthropogenically-induced desertification, resulting from the agricultural development of Israeli drylands. It was hypothesized that the main winds bringing loess to the Negev desert prior to the Holocene came from the Sahara, and as a consequence of the direction and great fetch of the wind, brought as much loess to the desert as that which was washed away each winter during the floods (Evenari et al.1982). Thus there was not net erosion during this period. Since the Holocene wind directions have changed and loess to the Negev desert comes from Saudi Arabia, a far shorter distance, and less loess reaches the desert to replace that lost in the floods. This results in net erosion, which is a natural process (Avni 1998). The Nabbatean people, who inhabited the Negev between 200 B.C. and 100 A.D., built tens of thousands of terraces in the wadis to stop this erosion and to facilitate the use of run-off agriculture (Evenari et al., 1982). However, such practices have stopped after the Byzantine period, the deterioration of the terraces’ walls continues, causing more gully erosion in wadi channels. Yet, though this erosion is a long-term process that started at the end of the Pleistocene (Avni 1998), Ward et al (2000) set out to explore a prediction that the rate of this erosion has increased exponentially since the advent of modern agriculture in the arid and semiarid region of Israel.

4.2.2 Indicators for soil degradation on semiarid agricultural land

 

Ward et al (2000) selected galleys within active agricultural land and within nature reserves in the arid – semiarid transition region in the northern Negev, receiving 250-350 mm of annual precipitation. Floods create waterfall within these galleys, and the researchers found that areas above waterfalls have better soil quality (as expressed by physical and chemical composition, as well as by results of a simple bioassay) than those below, probably due to soil nutrients decrease as one moves downstream from the head of a waterfall due to increased erosive impact This finding confirms that water erosion reduces productivity, but Ward et al (2000) also found that the effect of land degradation is more pronounced in agricultural areas than in nature reserves. Thus, not only galley erosion may have recently intensified, but also this intensification is linked to some sheet erosion and subsequent initiation of soil degradation in irrigated agricultural land, degradation that has not yet been expressed by a reduction in crop productivity.

 

4.2.3 Galley erosion due to overgrazing

 

The transition from a nomad, pastoralists’ society to a sedentary Bedouin society has had an initial positive effect on range and soils. However, though of much lower economic significance than during the pre-State period, Bedouins continue to maintain livestock. Furthermore, it is likely that socio-economic developments gradually increased grazing pressure, following its initial decline in the early years of the State (Pervolotsky 1999). This is because (a) the population increased from 11,000 immediately after 1948 to 120,000 nowadays (and utilizing ca 1000 km2 of semiarid and arid lands, Azmon 1999), (b) the migration of Bedouins have been replaced by heavy grain and hay supplementation, (c) the exclusion from some traditional grazing lands increased the pressure on other lands, and (d) the increased spatial availability of drinking water, together with accessibility to veterinary services, all led to an increased number of animals (the 70,000 sheep of 1960 increased to 80,000, 130,000 and 200,000 in 1978, 1980 and 1984, respectively [Abu-Rabia 1994]) and an increased grazing pressure on areas not transformed into irrigated croplands. Since many Bedouins tend to settle along major roads, to facilitate their transportation to urban centers and working places, their herds are maintained in these permanent residences along the roads, and overgraze several kilometers of both sides of the roads (during the dry season animals are maintained on purchased fodder). As a result, severe galley erosion is becoming evident along these major roads, especially in the semiarid region. In some regions, e.g. the Yatir forest, KKL is investing huge efforts to arrest this phenomenon, by (a) applying the “Savannization” afforestation technique, that should not only arrest galley and sheet erosion, but also improve range productivity; and (b) encourage local Bedouins to utilize the already existing Yatir forest for collection of firewood and for grazing.

4.2.4 Sheet erosion due to grazing

 

Following harvest, especially of cereals, in the semiarid areas, Bedouins are encouraged to introduce their herds to these croplands for feeding on the stubble. On the one hand, it is not known what is the contribution of this trampling and removal of soil cover to wind erosion during the end of summer, and water erosion by first rains. Surely this practice contributes to the economic profitability of free range livestock growing, and to the livestock intensified impact on vegetation cover and soil erosion during sites and times off the stubble-dependence periods.

 

4.2.5 Galley erosion due to road construction and use

 

Economical, social and military demands dramatically increased the number and extent of roads constructed all over Israel, both paved and non-paved ones. The desertification-related damage of these roads increases with aridity. Many of these roads have generated run-off that contributed to soil erosion and flush floods, and to severe ever-intensified galley erosion. The roads increased the accessibility of many regions to vehicles, which goff the roads and cause either compaction or breakage of crusts and grinding of soils. Both civilian and military vehicles contribute in this way to soil erosion and dust generation, which may jointly reduce vegetation cover (Rozin, U. 1997). In the hyper-arid Arava Rift Valley and in many arid areas the roads blocked and diverted floodwater and run-off courses, causing mortality of indigenous trees and other vegetation, instrumental in both soil conservation and range productivity. Up to 61% mortality of acacia trees in these areas was attributed to the absence of culverts under road cross-cutting the ephemeral river beds, where acacia trees abound, and five species of perennial plants disappeared downstream from roads (Ward and Rohner 1997). This damage to the vegetation, together with the intensified impact of the diverted runoff, contributes too to galley erosion.

 

4.3 Soil salinization

 

4.3.1 Current agriculture-related salinization

 

Surveys completed during last five years indicated that at least 110 km2 are prone to salinization and 40 km2 need rehabilitation, mainly in the northern dry subhumid region, on clay soils with high ground water table (Jezre’el Valley, Kharod, Beth-Sa’an Valley, Western Galilee, Benyamini et al 1998-9). Rehabilitation is already underway by subsurface drainage systems and adapted irrigation protocols. However, saline drainage water withdrawn from a field into a nearest trench, gully or river, can lead to salinization of rivers or nearest lands, which will require further disposal facilities and means. Finally, soil salinization, excess irrigation water and effluents and overuse of renewable water resources for agriculture, cause also salinization of water resources, which in turn, further salinize soils when used for irrigation. These already occurring problems in the dry subhumid regions may be minor, as compared to future potential risks in more arid drylands of Israel.

 

4.3.2 Irrigation with brackish water in the hyperarid and arid regions

 

Though the Arava Rift Valley is categorized as hyperarid because its precipitation is very low and the potential evapotranspiration there is very high, the natural productivity is in places relatively high - being a valley, its productivity is supported by runoff, generated by the high and extensive mountain ranges at both sides of the valley. Indeed, a chain of very successful agricultural communal farms (Kibbuzim and Moshavim) has been stretched along the Arava Valley. However, this oasis or patch agriculture is based neither on run-off nor on transported water, but on local groundwater, most of which of “fossil” origin, and brackish. Given the extremely high evaporation rates in that region, there is a mounting risk of soil salinization due to the continued dependence on this water. Such brackish water also abounds in the arid region, and plans of widespread and intensive use for vineyards and other crops in this region are underway, with a similar associated risk.

 

4.3.3 Irrigation with treated wastewater in the semiarid region

 

Three socio-economic and political trends have recently combined to induce a new salinization risk to large areas in the semiarid region, linked to intensified agricultural development of this region. First, population growth and the increase in standard of life intensified urbanization in the central and southern dry subhumid region of Israel, where most of the population is concentrated. This urbanization is at the expense of agricultural land, which has become prime real estate. Second, the increasing population generates ever-increasing quantities of wastewater, that in order to comply with international agreements for protecting the waters and beaches of the Mediterranean Sea, cannot be anymore disposed to that sea. Third, the amount of renewable freshwater required for satisfying the demand for domestic use increases, at the expense of freshwater for agricultural use. The proposed and already executed solution is to transfer the receding dry subhumid agriculture from the dry subhumid areas to the semiarid areas, and to irrigate this agriculture with treated waste water generated by the densely populated center of the country – agricultural production will thus continue, a new water source will become available for this agriculture and the Mediterranean Sea will not be polluted by Israel.

 

The total amount of wastewater generated in Israel is about 60% of the urban water supply (364 million m3). Around 310 million m3/year is treated. Of this, only a small amount is disposed into the sea and surface streams, while the bulk (255 million m3/year) is reused for irrigation (Eitan 1995). The Shifdan plant on the coastal sand dunes in central Israel is a large-scale project for wastewater treatment. The treated water is recharged to a nearby aquifer. The percolation of the water through the deep sand provides an additional cleaning phase, and the aquifer serves as an underground reservoir for the recharged water, preventing loss by evaporation. Water is pumped off mainly in summer, and more that 100 million m3 of this treated wastewater is transported annually via the "Third Negev Pipeline" to the western Negev for irrigation. Smaller-scale plants in the Negev provide treated wastewater for irrigation of fields located a short distance from the source of the effluent. This water is of inferior quality because of minimal treatment, and use is restricted to irrigation of crops such as cotton in the summer. Additional small and large plants are under construction and it is expected that most of the water allocated for agriculture will eventually consist of treated wastewater. Also, methods of sub-surface drip irrigation using treated wastewater are under experimentation, with good initial results.

 

These developments have two desertification risks. The first relates to the salinity of treated wastewater, which is higher than that mostly used in Israeli agriculture. All improvements with respect to treatment effectiveness attend the issue of health safety but not the risk of soil salinization. The second risk is related to the sludge, a sizeable by-product of the wastewater treatment process, which too cannot be disposed to the Mediterranean Sea. Sludge can be applied to increase soil fertility, which may be a great advantage for agriculture in the nutrient-poor dryland soils. However, salinity, heavy metals and other toxic compounds may abound in sludge, and its effect on dryland soils is still unknown.

 

Israel operates some 30 desalination facilities and in1997 Israel’s national water company Mekorot desalinated 9.8 million m3 of water, much of it for domestic use, especially in for the far south, which is out of reach of the National Water Carrier. The Negev fossil and brackish groundwater is good candidate for more desalination efforts, though desalination of treated wastewater requires more research.

4.4 degradation due to reduced grazing

 

4.4.1 Increased flammability, fires and soil erosion

 

The dramatic change in the status of the Mediterranean woodland due to reduced grazing and exploitation for firewood must have had an initial positive effect on soil and water conservation. However, the woodland flammability increased, and together with carelessness and criminally motivated arsonists, the frequency and intensity of damaging fires has increased (Safriel 1997), to the extent that in some cases such fires have caused spells of severe soil erosion (up to 10,000 times higher then in non-burnt areas, Inbar et al 1998). Re-introducing controlled grazing could have reduced fire risk and damage, but by that time the “Black Goat Law” and socio-economic trends made goat pastoralism a socio-economic non-viable option. Woodland management for wildfire control is one of the major challenges ahead.

 

4.4.2 “Bush encroachment”– loss of biodiversity and forage value

 

The improved condition of the Mediterranean woodland due to reduced grazing had an initial positive effect on biodiversity and the value of forage. However, the woodland has become dense and impenetrable, and due to intensified competition many herbaceous plant populationhave been out-competed. Furthermore, in some areas the scrubland expanded. Thus, former scrublands used by livestock have become impenetrable, and former grasslands have been penetrated by scrub vegetation with lower forage quality. These tow processes combined reduced the overall viability of livestock growing. Bush encroachment due to grazing pressure is in many countries the source of range degradation in drylands. In Namibia, for example, grasses out compete trees and bushes and limit their germination, but when grasses are overgrazed bushes are freed from this competition (Wiegand et al 1999). Such processes are not expected to occur in Israeli grasslands, due to their evolution with human impacts for many millennia (Pervolotzky & Zeligmann 1993). Instead, it was the reduced grazing that caused further constraints on grazing. Though the number of free-ranging livestock in Jewish farms is relatively small, this type of “bush encroachment” is another expression of an economically-tangible land degradation. It was found, though, that manual thinning and controlled grazing by goats increase the height and trunk diameter of the trees, thus improve penetrability of livestock to the woodland (Pervolotsky and Haimov 1992). Similar practices are also instrumental in preventing woodland fires (Pervolotsky et al 1992, Ettinger et al 1993).

5. Implementation of the CCD by Israel

 

5.1. Synergies in implementation

 

No decision has been taken in Israel with respect to preparing a National Action Plan to Combat Desertification (NAP). Since Israel has accumulated a rich experience in development of its drylands, in dryland agriculture, in plant breeding, in water resource development and management, in forecasting climate and in conservation of biodiversity, it is likely that Israel will produce a holistic and integrative action plan for sustainable development, which will incorporate its commitments a Party to all three “Rio Conventions”, the CCD, the Convention on Biodiversity (CBD) and the Framework Convention on Climate Change UNFCCC, as well as respecting the legally non-binding “Forest Principles”.

 

The need to explore the potential synergies derived by a joint implementation of the “Rio Conventions” was raised by the Delegation of Israel in the plenary of the Commission on Sustainable Development (CSD) in New York, in April 1995. As a result, an Expert Meeting on Synergies Among the Conventions on Climate Change, Biological Diversity and Desertification and the Forest Principles was convened in Sede Boqer, in the arid dryland of Israel, on March 1997 (UNDP 1998). Israel also provided consultation for the preparation of a document for the 3rd Session of the COP of CCD, in Recife, Brazil, 15-26 November 1999, dealing with strengthening the relationships and synergies between the CCD and relevant international agreements and organization, for promoting the combat against desertification (ICCD 1999).

 

5.2 Planning for promoting sustainable development

 

The growing environmental awareness, a committed environmental administration, and greater integration of environmental considerations into local, regional and national planning create an enabling environment for preparing a national action program for sustainable development of Israel. The Government of Israel has carried out two major relevant activities during the last five years. A Masterplan for the 21st century – “Israel 2020” was initiated in 1996 and was recently completed (Gabbay 1998). Though this Masterplan does not give much attention to the arid and hyperarid regions of Israel, it encompasses several objectives for a sustainable development policy in Israel:

 

 

For constructing a sustainable development strategy, seven target groups (industry, energy, transport, tourism, agriculture, urban sector, biodiversity) have been put to work. The groups were composed of a wide range of stakeholders including national government, local government, the private sector, academic institutions and NGO’s. The preliminary documents for each sector are presented in two documents (Ministry of Environment, 1996, 1998).

 

Issues pertaining to desertification in these documents are:

 

 

 

5.3 National Planning Workshop

 

The issue of combating desertification is not dealt explicitly in these documents and expert meetings. The first attempt to tackle the issue of combating desertification through a participatory planning took place in Mitzpe Ramon, in the Negev Highlands of Israel, on 27-28 April 1999 in a National Planning Workshop, organized by a joint Israeli, Palestinian, Jordanian Egyptian and Tunisian project, “The Initiative for Collaboration to Control Natural Resources Degradation (Desertification) of Arid Lands in the Middle East”. This Project has emanated from the Working Group on Environment of the Multilateral Middle East Peace Talks and facilitated by the World Bank. The objective of the workshop was to prepare the national strategy for combating desertification in Israel in accordance to the Goal Oriented Project Planning (ZOPP – German language acronym) method. The majority of the participants were researchers of the Blaustein Institute for Desert Research (BIDR) of Ben-Gurion University, the focal Israeli institution for the implementation of the CCD. Other participants came from the Peres Center for Peace, the Ministry of Agriculture, the Ministry of Environment, Arava R & D and the Facilitation Unit of the Initiative to Control Natural Resource Degradation (Desertification) in Arid Lands of the Middle East.

 

The workshop constituted a participatory approach that considered all point of views, experiences and backgrounds related to combating desertification in Israel and included the following elements -

 

 

 

The Jordanian moderator of the Planning Workshop observed that combating desertification is not a high priority issue and concern for Israel. Israeli knowledge and findings, however, might have the potential to help other neighboring countries in combating desertification in the regions (BIDR 1999).

 

The two results of the Planning Workshop are summarized in the following schemes.

 

 

 

As a result of this workshop, the Blaustein Institute for Desert Research compiled a Desertification Research Program that included 40 multidisciplinary project proposals (a) for elucidating the mechanisms of desertification; (b) for improving methods and practices of combating desertification; and (c) for assessment of desertification and efficacy of combating desertification (BIDR 1999).

 

5.4 National Committee

 

Israel has not established a National Committee to Combat Desertification. However, the Ministry of Foreign Affairs has established an Intra-governmental Steering Committee for Combating Desertification. Members of the Committee are representatives of the Department of International Organizations and the Peace Wing of the Ministry of Foreign Affairs, the Ministry of Environment, the Ministry of Agriculture and the Ministry of Science. Not governmental organization represented in the Committee is the KKL. The Committee is chaired by the a representative of the Center for International Cooperation of the Ministry of Foreign Affairs, and the Secretary is a representative of the Center for International Agricultural Development Cooperation (CINADCO). The Committee coordinates the desertification-related activities of the different governmental departments, and allocates budgets for these activities. The Committee appointed an Professional Advisory Sub-Committee, members of which are representatives of the Technion – Israel Institute of Technology, the University of Haifa, the Hebrew University of Jerusalem, Tel-Aviv University, Ben-Gurion University of the Negev and the Volcani Center for Agricultural Research. This Sub-Committee is chaired by representative of the Blaustein Institute for Desert Research, the Focal Point of the CCD for Israel. This Sub-Committee is charged by the Steering Committee with issues requiring professional opinion, and it advises the Steering Committee on budget allocations. One such activity is the implementation of the agreement between the Kingdom of Spain and the Government of Israel on joint research for combating desertification.

 

5.5 Outlines for a NAP for Israel

 

Though the Intergovernmental Steering Committee has not yet decided upon the need for Israel to construct and implement an NAP to combat desertification, some outlines for such a plan can already be roughly drawn. Since Israel has several types of drylands, goal to be achieved are listed by dryland types.

 

5.5.1 The dry subhumid drylands

 

5.5.2 The semiarid drylands

 

 

5.5.3 The arid drylands

 

 

5.5.4 The hyperarid drylands

 

5.5.5 NAP components common to all dryland types

 

Several components of the NAP apply to all dryland types and regions. These include:

 

 

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