Feature Sustainable Agriculture Methods to Combat Desertification The Israeli Experience1 Raanan Katzir Director Sustainable Agriculture Consulting Group (SACOG) 4 Efter St. Tel Aviv, 69362, Israel Tel: (-972-3)-6991381; Fax: (-972-3-) 6990152, E-mail: [email protected] Abstract investing in local research under desert conditions. The success or failure of desert Traditional desert nomad agriculture in Israel is based upon growing development depends on the human wheat under rain fed conditions and sheep grazing on harvested wheat fields, as factor. There is need for dedicated well as growing fruit trees in oasis. What characterize the desert are low manpower ready to settle in the desert and precipitation, high evaporation, diverse and extreme climatic conditions, intensive capable to use scientific and solar radiation and vast land areas. Israeli arid land is composed of five technologically advanced cultivation and distinguished regions, each with specific characteristics, resulting in few types of environment control methods needed for modern agriculture. Advanced agriculture in the desert takes advantage of successfully performing under adverse producing off-season vegetables, as well as flowers, fruits, mostly palm dates for desert conditions. For developing and local and export markets and fodder for animal husbandry. applying these technologies, abundant Cultivation of tilapia fish is also practiced widely, as is the raising of economic resources are required. ostriches. Greenhouses, in which growing conditions are fully controlled, are The desert is characterized by very common. Water is the most limiting factor. Water resources include: wastelands, low population density, a large conducting water from out-region resource, the use of saline and thermal water, number of sunny days with high the harvesting of rainwater, the recycling of sewage water and desalinized sea temperature and radiation levels and water. Drip irrigation to economize the use of water and using saline water, are scarcity of water. Usually, the few existing the dominant systems. Reforestation based upon soil conservation-works and limited sweet water resources are only rainwater harvesting is applied. found in oasis. However, in most deserts The main reasons for success in agricultural production under arid of the world exists deep saline water conditions, is the skilled and knowledgeable human resource. aquifers that may be utilized when applying Introduction agricultural development and production. specific technological methods. It is necessary to identify the advantages Frequently occurring excessive climate Agricultural production and and disadvantages of each of these phenomena, such as strong winds, sand desert conditions are usually considered characteristics and existing natural storms and extreme temperatures to be antagonistic or at the best resources before deciding on large-scale dominate the desert climate. incompatible. Since the desert is an area development. Modern agricultural production with adverse climate and soil conditions For developing modern methods, particularly for crops grown regarding as a marginal natural resource, agriculture, it is necessary to generate under protection in greenhouses which it is unattractive for modern agriculture, know-how and specific technologies are specifically developed for utilizing the even though it also has specific needed for the utilization of desert favourable properties of the desert, such characteristics, which could be useful for resources. This can only be done by heavily as high temperatures and intense sun 1 This article was presented by Dr Raanan Katzir at the ECHO’s Tenth Annual Agricultural Mission Conference, November 11-13, 2003, Fort Myers, Florida. 138 Natural Product Radiance Vol 3(3) May-June 2004 Feature Another part of the desert is a has high potential for adoption in the Sahel high plateau of 600-800 m.a.s.l. This area region of Africa or in other desert areas produces bulbs of flowers such as irises, in Africa, Asia and Latin America. Under narcissus and gladioli, as well as olives, this system, Eucalyptus trees can be grapes, melons and vegetables grown in grown for fire wood, Leucaena trees for open fields and in greenhouses. Also fodder for goat and sheep and olive trees Oranges on sandy soil tilapia fish are raised in greenhouses in for oil production for human radiation, for achieving high production thermal saline water. consumption. of biomass. Local saline water resources Similarly another part of the Another type of traditional are advantageously used for crop desert are the flat and hilly areas covered agriculture, practiced in the hilly loess- irrigation. Applying state-of-the-art by loess soils on which rain fed and soil area, is rain-fed wheat cultivation technologies in greenhouses makes it irrigated wheat, vegetables, flowers, during the rainy winter season. possible to control almost all factors forage, apple, apricot and citrus, mainly Precipitation in this desert area is around influencing plant growth, such as lemons, are produced. 200 mm per annum. This amount of temperature, humidity, radiation, The part of the desert near the rainfall can produce 2 tonnes/ha of wheat protection from wind, growth media and Mediterranean Sea predominantly consists grain. During summer, sheep and plant nutrients. of sand dunes. These dunes can be easily goatherds graze on the wheat trash. This One of the characteristics of the flattened and cultivated. By using drip is the type of agriculture characteristically desert specific loess soils is their very low irrigation integrated with fertilizer practiced by the nomad population of the infiltration rate, resulting in rapid sealing application, Israel’s most outstanding desert, the Bedouins. of the surface layer once the soil becomes agriculture is practiced on these once Under the new reality and habits wet and causing almost immediate water desolate looking sand dunes: citrus, of Israel, modern agriculture is developing run-off in the form of streams and flooding avocado, mango, vegetables, flowers. and has established itself in the desert. This even after a short rainfall. These run-off advanced agriculture, which the present waters can be harvested or captured and Desert Agriculture or article is dealing with, may be named directed into reservoirs for later use. Agriculture in the Desert “Agriculture in the Desert”. Israel is a small country in the Middle East with a total land area of about As early as almost 3000 years Water Resources 26,000 km2. Sixty percent of its territory ago, an ancient agricultural system known is desert, with rainfall not exceeding 200 as the Nabatean Agriculture was Modern agriculture in the desert mm/annum and limited to the five winter successfully practiced in the desert. This is firstly based on the availability of water months November to the end of March, system is based on water harvesting from for irrigation. We are distinguishing which is the only rainy season of the year. nearby bare slopes. The run-off water, between external and local water Only 10% of the total population of Israel directed to, and accumulated in cultivated resources. External water resources are lives in this area. However, the Israeli plots located at lower levels, is used for transported by the “National Water desert is not a homogenous complex. It increasing soil humidity. Various Carrier” over a distance of more than 300 includes the Arava Valley extending from vegetables and fruits like olives, almonds, km from the Sea of Galilee in the north of the south of the Dead Sea to the northern figs and others were successfully grown the country. part of the Red Sea, and which is part of under this system. Another external resource is the the Afro-Asian Rift Valley. Dates, mangoes, This system mainly fits small- recycled sewage water from the central vegetables, flowers and milk are produced scale subsistence farming and is not urban area of Tel Aviv and its satellites in this valley, part of which is below sea practically applicable for more advanced cities with a total population of 1.2 million level. agricultural systems. However, the system located 80 to 100 km to the north of the Natural Product Radiance Vol 3(3) May-June 2004 139 Feature target area. After secondary biological Among others, they include asparagus, solution to this set of problems. The treatment, the sewage water undergoes broccoli, beet-root, celery, cabbage, agriculture growing season in this area further treatment. It is filtered through tomato, melon, lettuce, Bermuda grass, lasts from September to May. sand dunes down to a depth of 80 m where Rhodes grass, wheat, sorghum, sugar-beet it is stored for a prolonged period of time. and cotton. These crops yield commercial Soils After reaching a very high quality almost yields under a saline water irrigation comparable to potable water standard, the regime. In some crops, as in tomatoes, The growing media in the water is pumped into the distribution the use of saline water for irrigation results greenhouses usually consists of sand system. in increased concentration of sugar in the which is especially brought from often far These two water sources from the fruits. In wine grapes, the grapes attain a away dunes, or special prepared material north are either immediately used by the high level of dry matter resulting in the consisting of mixtures of sand, compost, agricultural sector in the south or stored production of high quality wine. Using peat, vermiculite, etc., used as detached in very big reservoirs in the target area, saline water for irrigating olives also media. Rock wool, an artificial product, some of which may contain up to one improves their oil quality. is also in common use. Irrigation, million m3 of water. By using a special sealed pipe integrated with fertilizer application, is One of the local water sources is system installed near the plants, the fully computer controlled. The amounts the saline water stored in 1000 m deep thermal water pumped from the well is of water and fertilizers to be applied as aquifers.