Desertification is found to some degree on 30 per cent of irrigated lands, 47 per cent of rain-fed agricultural lands, and 73 per cent of rangelands. Annually, an estimated 1.5 to 2.5 million hectares of irrigated land, 3.5 to 4 million hectares of rain-fed agricultural land, and about 35 million hectares of rangeland lose all or part of their productivity due to land degradation.