Spatial Analysis of Agricultural Land Use Changes in the Khabour River Basin of Northeaster Syria

The Khabour River, southernmost tributary to the Euphrates, is a case study in the complexity of managing riparian resources. The river is located entirely within Syria but the watershed includes portions of Turkey and Iraq. Indeed, on account of the steep southward precipitation gradient in the region, the spring-fed Khabour is recharged almost exclusively by precipitation that falls on Turkish soil. For millennia the northern portions of the Khabour watershed have been used for rainfed agriculture. Until recently, however, cultivation along the dry southern stretch of the river was limited to the floodplain, where traditional gravity methods of irrigation could be practiced. In the last half of the 20 century irrigation initiatives in both Turkey and Syria fundamentally altered the human and hydrologic character of the watershed. First came broad introduction of the diesel-powered pump, which allowed farmers to draw on deep groundwater reserves from virtually anywhere in the basin. Next came major impoundment and diversion schemes. In the 1990s alone two major dams were constructed along the Khabour and plans to import water to the Turkish portion of the basin neared completion. We have used paired Landsat TM images from September 1990 and 2000 together with ASTER-derived digital elevation data and the statistical tools of landscape ecology to quantify changes in the distribution of irrigation projects in the Khabour watershed. Through these analyses we can describe the changing character of agriculture in this region, and by integrating this remotely sensed data with biophysical information on climate and hydrology it is possible to evaluate the hydrologic impact of various water extraction and diversion schemes.