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Abstract
Almost half of the Earth's land surface loses more water than it gains. As pressure for useful land increases, countries must consider management strategies for these drylands. Israel, which has carried out long-term agricultural projects in its wettest dryland regions, offers some lessons.
How sustainable is it to pump water into drylands to grow exotic
trees . . . or to turn deserts into gardens? Is it financially or ecologically realistic for countries to grow subsistence food on their drylands? What are the most sustainable options for using drylands?
Questions about how we use the world's drylands need priority attention from wealthy and developing nations alike. Approximately 47 percent of the Earth's land surface is dryland, land that loses more soil moisture from evaporation than it gets from rainfall. These regions have come face to face with the same pressures devouring the world's rain forests - demands for agricultural and urban development. Historically, these were lightly populated rangelands inhabited by nomadic herders. Today, they are the final frontiers for settlements and agriculture. And they are among the most vulnerable to land degradation.
Obviously, each country needs sustainable options for using its particular drylands. One classic resource for dryland research - a sort of global laboratory - is Israel. Two-thirds of this tiny country is in the Negev desert, a diverse dryland that includes three of the four global types of dryland. With standing-room-only conditions in the wetter one-third, Israel has focused four decades of research and experimentation on learning how to use its drylands.
The world has witnessed Israel's well publicized high-tech solutions to living under harsh conditions. Yet there is a risk that the global community is also taking home a faulty notion that we can convert the world's drylands into productive gardens, based on the popular belief that Israel made its deserts bloom.
Indeed, Israel made its wettest drylands (the subhumid and semiarid lands) bloom. And until recently, Israel was able to circumvent desertification of these drylands. But this is because of two important differences between Israel and most other developing countries. First, Israel has been willing to explore technological innovations for land use. Most of the immigrants who settled in Israel in this century brought experience in trade and small business, rather than cultural farming or ranching traditions. So Israel was forced to develop its own dryland agricultural traditions from scratch, with novelties not confronting resentment and suspicion due to tradition. When it came to raising livestock, Israel's newly created ranchers preferred indoor practices, which avoid overgrazing problems, rather than free range grazing.
Second, Israel has had the advantage of a strong central government that could invest in national water resource development projects and research. Israel was able to provide its dryland farmers with rich, relatively high-quality water, transported long distances from regions where water is relatively plentiful. Having succeeded in this, Israel could also use high-tech agriculture and advanced water resource development to develop arid and even semiarid lands. Because of research, the Israelis were also aware of the environmental limitations of their drier lands, so Israel developed them only in favorable patches and created scattered man-made oases. Farmers in developing countries do not have access to investments of this kind, and when limited to their own means, they are restricted to the scant and low-quality water within their reach.
There is one more revealing clue to Israel's fame as one that "made the desert bloom," a point of which many desert agriculture advocates are unaware. Israel's reputation comes mostly from forestry development in the semiarid northern Negev, the wettest section of the Negev. So Israel cannot claim that it "greened the desert," since most of the Negev desert, which is arid and hyperarid, is not green, and will not be green, save the few but lush man-made oases.
It makes perfect sense: why wouldn't Israel invest most of its efforts in the least dry part of the Negev, the semiarid sections. In Israel, as in the rest of the world, the least dry drylands are more amenable for agricultural development. However, these drylands are also exposed to the heaviest human pressure, so they become degraded, either through soil erosion or through soil salinization or both, and often to the point of irreversible desertification. Yet, this advanced desertification has not happened in Israel yet, something for which this country should be and is hightly praised.
However, in recent years the semiarid northern Negev has come under mounting pressure for more agricultural and urban development. Signs of soil erosion and salinization, namely of early desertification, have become increasingly obvious. Furthermore, severe soil salinization is apparent in the dry subhumid and intensively cultivated Jezre'el Valley and some other dry subhumid and semiarid areas. Urbanization, road construction, overutilization, and pollution of water resources are also interfering with the land's natural resources such as wildlife and natural water supplies. The delicate biodiversity of drylands, which is instrumental in providing many ecosystem services and goods, may be taking the hardest hits from development.
Some of the most important lessons from Israel's experiences point to the limitations and problems associated with developing drylands. They suggest that the best environment for producing food, especially subsistence crops, is not on drylands, but in highly productive - namely in temperate - regions. It will always be more expensive to grow conventional subsistence food in the drylands than in nondrylands. So what are the drylands good for, given the Israeli experience?
The main message for developing countries is this: instead of fighting the disadvantages of drylands, people should exploit its assets. Look for the dryland attributes that nondrylands lack, such as an abundant, stable, year-round supply of solar energy that can substitute fossil energy, year-round sunshine for plant growth, mild winters for cold-sensitive crops, and an abundance of brackish water that is poor for subsistence crops but advantageous for cash crops.
Israel is one of several countries using the desert's sunny assets and brackish water for aquaculture (fish farming in greenhouses), for growing algae and algal products, and for growing pricey cash crops in greenhouses. In addition, dryland tourism is one of the hottest options that Israel is currently exploring. All these options use very little land, so they do not have an impact on the fragile dryland soil that is so sensitive to erosion and salinization.
As promising as these sustainable options look, it won't be easy for many dryland countries to emulate Israel's experiences. Each country needs financial investments and high technology to exploit dryland assets and generate competitive development. The problem is, most dryland people don't have access to technology and credit and lack the necessary marketing infrastructures, so they cannot develop their drylands in a sustainable manner.
Uriel Safriel is the director of the Blaustein Institute for Desert Research of Ben-Gurion University of the Negev (and a professor in ecology and zoology at the Hebrew University of Jerusalem). Since 1993, he has represented Israel in the Intergovernmental Negotiating Committee on the UN Convention to Combat Desertification. Since 1998, he has served as a member of the Intergovernmental Panel of Climate Change.
Andrzej Krauze is an illustrator, poster maker, cartoonist, and painter who illustrates regularly for HMS Beagle, The Guardian, The Sunday Telegraph, Bookseller, and New Statesman.
Learning to Live with the Desert - see also this HMS Beagle Profile by Corliss Karasov.
Office of Arid Lands Studies - information resources on arid lands, conferences, and the Arid Lands Newsletter. From the University of Arizona.
Bright Edges of the World: The Earth's Evolving Drylands - an electronic exhibit of the world's drylands. Developed by the Smithsonian Institute and United Nations Environment Programme.
Dryland Farming in Palestine - an in-depth look at dryland farming from the Applied Research Institute.
Land Degradation and Desertification - outlines the nature, status, and policies for controlling desertification. Extensive links to relevant articles. From the Center for International Earth Science Information Network at Columbia University.
University of California Sustainable Agriculture Research and Education Program - provides basic information as well as production techniques, news, and publications.
Sustainable Agriculture Network - a gateway to news and information from the Sustainable Agriculture and Research and Education Program.
