Chapter 2. Agro-ecological zones and farming systems

Agro-ecological zones

Although generally dry, the Syrian Arab Republic is a country that encompasses a great diversity of agro-ecological conditions and rural production systems. The main factors determining the agro-ecological diversity are climate, landforms and geological parent materials. The Syrian Arab Republic is located at the tip of the Fertile Crescent and lies entirely within the range of a major precipitation gradient, varying from about 1 500 mm in the west of the country to less than 100 mm in the southeast.

The Syrian Arab Republic has been divided into five agricultural stability zones (Figure 2), according to the average annual rainfall. The zones are defined in terms of suitability for rainfed crop production, and to some extent the probability of rainfall.

Figure 2 Agricultural stability zones in the Syrian Arab Republic

Zone 1

Annual average rainfall of over 350 mm. The zone is divided into two areas:

A. Areas with an annual average rainfall of over 600 mm where rainfed crops can be grown successfully.

B. Areas with an annual average rainfall of between 350 to 600 mm, but not less than 300 mm during two thirds of the monitored years, and where it is possible to grow two successful crops every three years. The main crops are: wheat, legumes and summer crops such as melon and watermelon. The area of this zone is 2 698 000 ha, accounting for 14.6 percent of the national area.

Zone 2

Annual rainfall of 250 to 350 mm in not less than two-thirds of the monitored years. It is possible to grow two barley crops every three years. Beside barley, wheat, legumes and summer crops are grown. The area of this zone, 2 473 000 ha, forms 13.4 percent of the national area.

Zone 3

Annual rainfall of 250 to 350 mm with not less than 250 mm during half of the monitored years. It is possible to grow one or two crops every three years. The main crop is barley but legumes may also be grown. The area of this zone, 1 306 000 ha, accounts for 7.1 percent of the total national area.

Zone 4

A marginal zone between the arable zones and the desert zone with an annual rainfall between 200 and 250 mm and not less than 200 mm during half of the monitored years. This zone is suitable only for barley or for permanent grazing. The area of this zone, 1 823 000 ha, forms 9.8 percent of the national area.

Zone 5

Desert and steppe zone. This area covers the rest of the country and is not suitable for rainfed cropping. The area of this zone is 10 218 000 ha and accounts for 55.1 percent of the total national area. There are some areas in this zone adjacent to rivers, which permit irrigated agriculture, but most part of this zone provides only sparse natural rangeland. As rainfall decreases towards the interior it becomes desert.

The average and the minima and maxima rainfall rates, between 1989 and 1999, in the different zones are given in Table 1.

The main field crops in the different zones are given in Table 2.

Farming systems

The system of agricultural stability zones was introduced in 1975. It was part of the overall effort by the Government to regulate agricultural production through medium and long-term agricultural sector planning. This central planning exercise involves a comprehensive annual agricultural plan specifying the crops that farmers should grow and the area planted to each crop in each of the zones and administrative units. Farmers in a particular zone may be required or allowed to grow certain crops and to use fertilizers, selected seeds or other inputs, if available.

ICARDA has been working in the dry areas of the Syrian Arab Republic for more than 20 years and has classified the farming systems in the Syrian Arab Republic as well as those in the West Asia and North Africa region (WANA) region into: deserts, steppe and native pastures, the barley/livestock system, the wheat-based system and the highlands (ICARDA, 1989).

In the desert areas only irrigated agriculture and nomadic grazing are possible.

In the steppe and native pastures systems, where the rainfall is below 200 mm, steppe occupies most of the land area. It is too dry to crop, although at the wetter margin of the steppe there is an increasing tendency to grow barley. Originally, this was shrub, steppe or even woodland. Today, steppe land is characterized by ephemeral vegetation of very low productivity. Even where rainfall exceeds 250 mm, it is native pasture that occupies pockets of land which are too steep and/or stony or where the soil is too shallow to grow crops. All but a few perennial plants have long since disappeared, mainly due to overgrazing.

Steppe land and native pasture are used primarily for the communal grazing of small ruminants. Only rarely can they support livestock year-round. They are grazed mainly in winter and spring. For this reason, production systems using these land types are generally integrated, based on barley/livestock or wheat-based systems. Steppe land in the drier areas shows evidence of severe degradation with low plant numbers. Legumes are particularly scarce.

The barley/livestock system is adopted in areas adjacent to the dry steppe, with an annual rainfall of between 200 and 350 mm. Here, livestock production, principally sheep and goats, is the dominant enterprise. Farmers derive the bulk of their income from the sale of dairy products, meat, and wool. Barley is the most common crop, although wheat is important in some areas. Both crops are grown using traditional practices and materials. In the case of barley, both grain and straw are used as livestock feed. As mechanized tillage has become more readily available, continuous barley production is becoming more common, despite the practice being detrimental to yield (ICARDA, 1989).

Where farms are large or animal populations are low, barley may be grown as a cash crop, with the stubble rented out for grazing by migrating flocks. The potential of the barley/livestock system is low and production is more variable than in the wheat-based system. The productivity of arable land within this system can be increased by using improved cultivars, by applying fertilizers to cereals and by replacing continuous barley cropping with legumes. Because production is low and variable, few farmers are prepared to risk investment in costly inputs. Instead, they respond to increased demand for livestock products by cultivating more and more marginal land for barley production and by overgrazing natural pastures and steppe.

Surveys have found that barley grain yields average about 500 kg/ha (Mazid and Hallajian, 1983) and only about 10 percent of farmers use fertilizer on barley (Somel et al., 1984). Due to the low and variable rainfall, farmers perceive the application of fertilizers in these areas as risky and supply and credit policies did not encourage their use (Mazid and Bailey, 1992; Somel et al., 1984).

The wheat-based system is located in areas with rainfall between 350 and 600 mm. Above 450 mm, bread wheat predominates while elsewhere durum wheat is more common. Rotations of wheat with food legumes and summer crops such as melon are common. Among the legumes, chickpea predominates in the wetter areas and lentil in the drier areas. Where there are local water supplies from wells or rivers, supplementary irrigation of both winter and summer crops is profitable and is becoming increasingly common. The potential of wheat-based systems is relatively high and farmers are financially more secure. National agricultural research has devoted most of its resources to these areas and in many cases has been successful in developing improved technologies. Where these have been supported by appropriate policies, farmers have adopted them rapidly.

The average annual rainfall in the highland areas is about 600 mm, with snow cover for up to four months of the year. The soils are degraded, low in organic matter, with a high pH and poor moisture-holding capacity. Soil erosion is common. The production systems of the highlands in the Syrian Arab Republic are broadly similar to those of the lowlands but are heavily oriented towards raising livestock and winter cereals (sheep, wheat and barley). Crop growth is constrained by relatively low temperatures and short growing seasons. These areas have received little attention from agricultural research. This is because of their remoteness and lower productivity compared to the lowlands. Nevertheless, there is considerable potential for improving farming systems in such areas.

The main crop and livestock systems in the different regions are given in Table 3.

The relative importance of arable crops and vegetables, irrigated and rainfed is shown for winter crops in Table 4 and summer crops in Table 5.