IntroductionAncient farmers in the Israeli Negev used technologies that have been lost, to produce sustainable, if not abundant, crops under conditions currently deemed unsustainable. Modern emphasis on artificial irrigation, mechanization, intense farming, varietal improvement, and use of chemicals has pushed proven, ancient technologies out of the picture. Restoration of those technologies stands to return sustainable production to the Negev, to provide livelihood to a growing population, to renew confidence in our forefathers (who knew more than we credit them), and to restore enthusiasm for writings of the sages, e.g. Seder Zeraim from the Mishnah, and to increase tourism to the area.
BackgroundMuch of the world's population lives on arid and semiarid land, where historical technologies, especially of water use, have been forgotten or abandoned. For example, archaeological observation indicates that in the first centuries CE the central Negev supported populations vastly increased over the current indigenous population. Some time after the destruction of the Kingdom of Judah by the Babylonians in the sixth century BCE, the new nation in the Negev, the Nabateans, built a magnificent civilization there, the achievements of which excite the imagination and admiration of visitors to the region to this day. Starting as nomadic traders, the Nabateans in time became superb architects and engineers, as well as expert hydrologists and diligent cultivators. To maintain a population of many thousands, the Nabateans had to develop agriculture in order to ensure a livelihood for their people. Similar population numbers continued even after the Romans annexed the region and made it a frontier province. After the division of the Roman Empire and the establishment of Byzantium, the entire eastern realm of the empire enjoyed a period of stability. The Negev became still more densely populated, and the technical achievements of the era surpassed even those of the Nabateans when they were independent.
Because permanent rivers are totally absent in the Negev, and even springs or proper locations for digging shallow wells are few and far between, the major source of water for humans, animals and crops could only be the collection of surface run-off obtained from sloping ground during winter rains, a technology that has been called "water harvesting" or "runoff farming." While cisterns, artificially constructed reservoirs filled by directed surface flows during each infrequent rainstorm, could be used to water humans and animals, run-off water was the only feasible source for irrigating crops. Modern archaeological observations demonstrate that run-off from winter rains was gathered from adjacent slopes and directed to bottomland fields for periodic soakings, to accumulate and store sufficient water in the soil to produce crops. Although the Negev's average winter rainfall is only about 100 mm, the run-off farmers were able to gather and concentrate sufficient run-off from the barren slopes to develop intensive agriculture in the depressions and bottomlands, which constituted only some 5 per cent of the total area in the northern Negev Highlands subregion.
The cultivated area was usually divided into small fields, which were leveled and terraced to ensure the efficient spreading of water as well as the conservation of both water and soil. Cross terracing, perpendicular to the axial slope, transformed the wadi into a continuous stairway, with stairs perhaps 10-40 m wide and 20-50 cm high. Terrace walls were designed to serve two purposes: spread the floodwater across the floodplain, and prevent erosion that would be caused by a concentrated stream. The slowed-down cascade from one terrace to the next could thus irrigate the fields sufficiently for a crop to be successfully grown. Data indicate the fields typically ranged from 0.1 to 0.5 ha. Archaeology also indicates that fields were combined to form farms of 0.5 to 5 ha. Farming communities covered several ha. The remains of some 150,000 such farm units are spread throughout the Negev, most commonly around the principal ancient towns. Maybe 10 per cent of them have been mapped and studied archaeologically by Moti (Mordechai) Haiman, and filed in a database hosted by Mnemotrix Systems, Inc.
Each field or farm was served by a particular well-delineated portion of its watershed. An elaborate system of well graded terraces and conduits was constructed to collect run-off from specific sections of the adjacent slopes, and direct that runoff to each terraced field within the farm. The complete field or farm necessarily comprised both the slope catchment (the run-off-contributing area) and the bottomland fields (the run-off-receiving area). Fields could be made sustainable only if associated with a catchment from slopes, since the meager rainfall alone was far from sufficient for any economical crop. Of course the larger the catchment, the greater the water supply one could expect, and the larger the corresponding plot of land that could be irrigated. Clearly defined catchment areas, allocated to serve particular farm units, constituted "water rights," as specified in the ancient documents found in the region.
Archaeological observation indicates that the ratio of run-off-contributing catchment area to runoff-receiving crop land area varied from 17:1 to 30:1, averaging 20:1. If we approximate the average annual rainfall as 100 mm, and if each hectare of sloping land contributed only 15 per cent of its annual rainfall (15 mm X 20), then the receiving crop land would receive 300 mm. Added to its own reception of the annual 100 mm of rainfall, the plot would thus receive a total of 400 mm, just enough to produce a crop. If, however, the run-off yield constituted 20 per cent of annual rainfall, the amount of water received by the field would equal 400 plus 100, for a total of 500 mm, an amount almost equivalent to the rainfall of the relatively humid habitats along the Mediterranean coast of Israel.
The fraction of rainfall yielded by any given watershed varied, of course, from rainstorm to rainstorm and from year to year. Gentle showers contributed practically no runoff, whereas intense storms might yield 30 per cent of their rainfall. To improve the runoff efficiency, and reduce the risk from lower than average rainfall, Negev run-off farmers apparently did more than merely gather natural runoff. Archaeologists have clear evidence that they actually tried to induce more of it. The hillsides in the Negev are naturally strewn with a pavement of stones and gravel, which inhibits and detains the flow of runoff over the surface. The ancient runoff farmers deliberately cleared the stones off the slopes and thus smoothed the surface and exposed the finer soil, to facilitate the formation of a self-sealing crust, of significant importance to runoff production. Consequently, archaeologists and travelers have found countless heaps, mounds, and strips of gravel on many hillsides, particularly in the vicinity of Shivta, Avdat, and Nitzana. Field trials in that region have shown that the practice of removing the surface gravel can increase the run-off yield by 8 to 20 percent.
That water harvesting, or runoff farming, made agriculture productive and sustainable is evidenced by wine and olive presses throughout the area, by threshing floors, and by farm houses in and near the wadis. Such structures would not be built throughout the area if agriculture did not support them, defined as Sustainable Agriculture.
In summary, evidence proves that ancient farmers practiced technologies that are no longer popular, but probably recoverable because of archaeological findings. Evidence also proves that agriculture was productive and sustainable.
NeedRestoration of ancient agricultural technologies to the Negev is needed for several reasons. A growing Negev population is producing families who need a livelihood, and, maybe more importantly, a connection to the land. Sociologists agree that there is something uniquely spiritual, yet uniquely primeval, in people connected to a land. Even for those who work in a sophisticated and mobile culture, simply to grow flowers or food in the earth is mentally and emotionally satisfying. Restoration of roots, e.g. agricultural technologies, brings a sense of satisfaction that cannot be found elsewhere.
Restoration of ancient agricultural technologies to the Negev will bring diversity to a country whose agriculture is intense and agronomically focused. Diversity is a proven method of reducing the impact of adverse events on agriculture, e.g. epidemics, drought, climatic change and economic change.
Restoration of ancient agricultural technologies to the Negev will bring tourism to the area. Tourists to Israel are more interested in the history of the land than in its modern implementation. Most current tourist attractions are in the central and northern areas of the country. Restoration of agriculture to the Negev, initially in selected areas, will serve as focal points for development of tourism, including sleeping and eating facilities.
Restoration of ancient agricultural technologies to the Negev will add interest in Torah to both Israeli and tourist. Peoples of the Tanakh were agriculturalists by and large, probably 90 per cent. The Torah was given to an agrarian culture, so much is said about agriculture. Many principles of Torah can be dynamically illustrated by a restored agriculture in the Negev.
And finally, restoration of ancient agricultural technologies to the Negev will improve the economy of the region, and therefore of the nation. Negev agriculture will add to the GNP, increase employment and increase the need for supporting services, both there and elsewhere in the country.
ConceptThe time is right, from many aspects, to restore ancient agricultural technologies to the Negev through a combination 5-year research and demonstration effort. Recent archaeological observations prove them to be a sustainable set of technologies, in a relatively large area of the country, as evidenced by mapping. Renewed interest in the Negev is increasing daily. Just today, Meir Sheetrit, the Transportation Minister and Likud veteran was quoted as believing that, "the 'true Zionism of tomorrow' is to settle the Galilee and the Negev." Restoration as the prophets prophesied is abounding. An excited initial team of experts, eager to contribute as they learn, has been assembled. Let's roll!
Proposed is a recovery/demonstration farm, occupied by an Israeli family, laid out and farmed according to known ancient technologies. Said farm would produce agricultural products for consumption and sale, and serve as the focal point for selected research projects designed to study and fine tune known practices. Known are the archaeologically observed technologies of terraces to divert watershed runoff to benched, leveled fields. Restoration of these fields will provide the resource necessary to demonstrate the sustainability of ancient agricultural technologies, the feasibility of Low Input Sustainable Agriculture in a modern world.
Proposed is selection of 1 or 2 ancient area farms where benched fields were historically fed water by an upslope terrace system. To simply restore the ancient agricultural water technologies, (1) each field should be leveled to provide uniform infiltration of water across the field, eliminating wet spots and dry spots in the field, as was done by the ancient farmers. (2) The terrace system of the contributing watershed should be restored to functionality, as was done by the ancient farmers. (3) Crops should be planted to optimize the match between sustainability, productivity, economic feasibility, climate and history. In the case of perennial crops, artificial irrigation the first and maybe second year will ensure uniformity of stand and objective understanding of their relative place in Negev farming using ancient technologies. Protection from grazing animals and humans will be important.
Concerning selection of crops to be grown on the demonstration farm, Deuteronomy 8 gives a good start: "a land of wheat and barley, of vines and fig trees and pomegranates, a land of olive oil and honey." Selection criteria should include, but not be limited to, temperature amenability, depth of rooting system in the selected soil (to mine the stored water in the root zone), drought resistance, local insect and disease resistance, and usability for local consumption or marketability. Each farm should include 7 to 10 fields, to include the option of planting each to one of the seven species, and to provide option of a few other appropriate crops. For reasons of sustainability, tourism and risk reduction, crops excepting the shivat haminim should be limited to historically proven ones, e.g. almond, carob, and wild oats (Avena sterilis). Inclusion of date palms is problematic, but not out of the question, because they require 5 or 6 times as much water as other fruit trees, although the water can be very saline because date palms are highly salt tolerant.
Extension of the demonstration farm goals beyond simple restoration of ancient agricultural technologies should consider marketing of products from the farm in the nature of boutique, "Biblical" processed products, e.g. wine, bread or flour, olive oil, pomegranate juice or concentrate, and date honey.
Restoration of the farm(s) to productive state will not be an instantaneous event. Instead several months of labor by several individuals will be necessary to level the fields, restore the terrace system and plant. While mechanization of earth moving is tempting, animal and human labor is preferable because of reduced disturbance to existing profiles, and because of the tourist attractiveness of the work.
ResearchIn addition to the recovery/demonstration goal of the selected farm(s), a research goal or set of goals is very significantly appropriate, to make it (them) a recovery/demonstration/ research farm(s). While it is true that the ancient technologies were successful, our knowledge of them can be enhanced by non-invasive research. Furthermore such research knowledge can be propagated into other scientific and geographic areas of the world. Not only will the Negev and Israel benefit from such research, but the acquired intellectual properties will be easily exported to the known world.
For research purposes, homogeneity of crops within each field is important, i.e. each field should be planted uniformly with one species and a crop stand should be a priority, guaranteed for perennial crops by artificial irrigation if (probably) necessary. If, however, investigation of the soil profile within a field indicates acceptable uniformity, the field might be planted at, say, three different densities to allow planting density vs yield determination, data which are not archaeologically available. Further, crops must be protected from humans and animals.
In spite of the demonstrated success of ancient agricultural technologies, several questions or topics exist which are amenable to answer via research on the demonstration farm(s), in no certain order:
Define soil properties of both wadi flood plain and contributing watershed slopes (data acquisition intensive):
- Soil type
- Soil depth
- Mechanical analysis of the profile
- Specific water storage capacity of the soil profile (flood plain)
- Native infiltration capacity
- Infiltration capacity as affected by surface crusting
Define, from historical and observed data, the area agro-climate (data acquisition intensive):
- Precipitation statistics
- Distributions of daily means by day of year
- Seasonal means
- Intensity vs duration curves
- Distributions of weekly evapotranspiration rates: Evapotranspiration rates as affected by species, climate, soil water content, etc. Water balance studies, including study of water holding and water use efficiency by specie.
The impact of surface preparation and disturbance on runoff and surface crusting. The temporal nature of surface crusting. Field testing.
Runoff amounts as a function of rainfall intensity, duration, soil condition, slope, etc. Can probably be modeled and verified.
The impact of seasonal rainfall variations on sustainability of selected crops grown under water harvesting technologies. Can be modeled.
The impact of terrace porosity (that allows water to percolate through the terrace) to watershed effectiveness in providing water to the receiving field, as a function of length, slope and construction technique. Field testing.
Optimal ratio of field area to contributing watershed area(s). Can be partially modeled.
Yield capacities of ancient agricultural technologies, by species and soil characteristics. Summary of production data.
ImplementationRestoration of a Negev farm to ancient agricultural technologies is not an overnight transformation. Patience, commitment, funds and organization will be required. Physically rebuilding the water control system of a 7 - 10 field farm is estimated to require ca 2,000 man days. Meteorological and hydrologic equipment is required. Organizational, operational and monitoring personnel are required. Planning, planning and more planning is essential. Commitment of funds and personnel for at least 5 years is mandatory; 7 years will probably be necessary to fully evaluate the economics of tree production. This is not a short-term project. But both the walk and the destiny will be highly rewarding! Let's roll!
Summary and ConclusionsAncient farmers in the Israeli Negev used technologies that have been lost, to produce sustainable, if not abundant, crops under conditions currently deemed unsustainable. Archaeological observation indicates that the central Negev supported vastly increased population in the first centuries CE over the current indigenous population. Restoration of those ancient technologies stands to return sustainable production to the Negev, to provide livelihood to a growing population, to renew confidence in our forefathers (who knew more than we give them credit), to restore enthusiasm for writings of the sages, e.g. Seder Zeraim from the Mishnah, and to increase tourism to the area.
The time is right, from many aspects, to restore ancient agricultural technologies to the Negev through a combination 5-year research and demonstration effort. Recent archaeological observations prove them to be a sustainable set of technologies, in a relatively large area of the country, as evidenced by mapping. Renewed interest in the Negev is increasing daily. Restoration as the prophets prophesied is abounding. An excited initial team of experts, eager to contribute as they learn, has been assembled. Let's roll!
Proposed is (1) a demonstration farm, occupied by an Israeli family, laid out and farmed according to known ancient technologies. Said farm would produce agricultural products for consumption and sale, and serve as the focal point for selected research projects designed to study and fine tune known practices. (2) In addition to the demonstration goal of the selected farm(s), a research goal or set of goals is very significantly appropriate. While it is true that the ancient technologies were successful, our knowledge of them can be enhanced by non-invasive research. Furthermore such research knowledge can be propagated into other scientific and geographic areas of the world. A few key research topics are delineated.