any people view the countries of the Arabian Peninsula--Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, the United Arab Emirates and Yemen--as basically desert lands, and they are not far wrong. Some places may receive no rain at all in a year. There are some exceptions, of course, such as Ibb in Yemen, which is at high elevation; and Salalah in Oman, which receives summer monsoon rain. But total average yearly rainfall in the region ranges from below 50 mm to about 250 mm. Also, temperatures can exceed 50oC, among the hottest on earth.
      These conditions mean that the plant-growing season ranges from nothing to about 150 days, hardly enough to grow any of ICARDA's traditional commodity crops. The Arabian Peninsula occupies some 246 million hectares, but a mere 2% of this is cultivated with arable or irrigated crops. However, this by no means implies that the rest of the land is useless. There is agriculture of a different kind, because nearly half of the land exists as pasture. It is not surprising, therefore, that livestock production is the main type of agriculture, in the form of sheep, goats and camels. It is estimated that there were 11 million sheep, 8 million goats and 841,000 camels in 1993, and                     

that these numbers represented a significant increase over the previous 15 years.
      Unfortunately, these increasing animal numbers are resulting in the over-exploitation of the fragile rangeland. As elsewhere in West Asia, the rangelands in the Arabian Peninsula are considered a common resource, and farmers practise open-access grazing by allowing their animals to roam free to find food where they can. Trees are also 'lopped' for fodder, and wood is harvested for fuel, timber and charcoal. Over 90% of the total land area now suffers from some form of desertification, and 44% is severely or very severely degraded.
Overgrazing of arid rangeland does not instantly result in devegetated sand dunes, but it can over time. However, the initial effect of overgrazing is to change the plant species composition of an ecosystem. The palatable species are consumed by animals very quickly, leaving an ecosystem dominated by a few unpalatable species. These species nevertheless hold the sand. If the grazing pressure continues, animals will be forced to eat even those species which they dislike. Cyperus conglomeratus, which is usually never grazed, was found to have been grazed in the Wahiba Sands of Oman, where it was         

one of a handful of surviving species. When even the unpalatable vegetation begins to disappear, the sand starts moving and a classical sand dune desert forms.
Many of the rangelands in Oman and the UAE appear to be supporting an abundance of vegetation. On closer examination, however, it is found to consist of a relatively few unpalatable species such as the attractive-looking, but unpalatable Calotropis procera. Along with this change in vegetation composition and abundance is a decline in the potential productivity. In the most severe situations such as in Al-Jouf in Saudi Arabia and Salala in Oman, not only have the unpalatable species disappeared, but so has the soil!