Land management strategies to sustain productivity of olive groves on steep slopes in Northwestern Syria

Abstract

In the northern hills of Syria, land degradation is a serious problem, particularly on vulnerable agricultural land. The traditional olive production land-husbandry practices have not kept pace with the intensification and expansion of into steeper areas. As a result, soil erosion is widespread due to intensive clear-tillage and the near absence of soil-conservation measures. Olive farmers seem well-aware about the risks of severe land degradation, but few farmers seem to find a suitable solution for this issue. Therefore, an on-farm research was conducted from 1997 to 2003 in two olive orchards in Yakhour village to develop, test and refine options for better land management that have the potential to stabilize and increase the productivity of olive groves in steepland. Two packages of soil and water conservation measures: An ëagronomic packageí designed to increase vegetation soil cover (by vetch intercropping), reduce soil disturbance (by minimizing tillage), and enhance soil structure (by incorporation of manure, and enhancing short-term chemical soil fertility (by application of mineral nitrogen, phosphorus and potassium). A second ëstructural packageí was based on designing and building earthen, semi-lunar shaped water-harvesting terraces, combined with the measures of the first package. Emphasis was placed on those soil and land- management practices that reduce soil erosion and help restore soil fertility. The applied soil and water conservation measures increased soil fertility status, soil organic carbon content and soil structural stability and reduced soil and nutrient losses. The improved soil parameters were associated with a marked increase in olive productivity of 25 - 75%. Farmers evaluated the packages and some of the measures are now being practiced by farmers.