Degradation and rehabilitation of agricultural land in North Syria
1988
Cocks, P.S. | Thomson, E.F. | Somel, K. | Abd El-Moneim, A.
The farming systems of north Syria are described with emphasis on small farms in the north west. The farmers are mainly producers of cereal and livestock, the latter increasing in importance as rainfall decreases. Most cereals are grown in rotations although there is a tendency for continuous cropping in the drier areas. Other components of the rotations are fallow, lentils, summer crop (watermelon and sesame) and chickpeas. Livestock graze non-arable (marginal) lands, crop stubbles, and the dry steppe, and are fed a wide variety of energy and protein supplements including barley grain, barley straw and by-products of cotton. Cereal yields range between 100 kg/ha and 2 t/ha and are strongly dependent on rainfall. There is evidence of degradation in both arable and marginal lands. Original tree and shrub vegetation disappeared to be replaced mainly by annual plants. Productivity of marginal lands is related to number of plants and the presence or absence of annual legumes. Legumes in dry areas are rare and plant numbers are substantially below optimum. Soils on marginal land are substantially more fertile than arable soils, indicating very severe reduction of soil fertility in the latter. Continuous barley growing is detrimental to yield and this practice is becoming increasingly common. Rehabilitation of dry marginal lands is possible by planting edible shrubs, especially several species of Atriplex and the return of capital invested in edible shrubs may exceed 20%. In wetter areas use of phosphate on native pasture may also be economically viable. Productivity of arable land can be increased both by applying fertilizers to cereals and replacing fallows with legumes. The use of either forage (Vicia sativa) and pasture (Medicago spp) legumes will result in substantial economic benefits. Superphosphate on cereals, tested widely in Syria is a relatively simple way of increasing productivity and profitability
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