Sustainable use of marginal lands to improve food security in the United Arab Emirates
In the United Arab Emirates (UAE), about 34 percent of the area is affected with different levels of salinity, where growth of normal plants is almost impossible. The extremely low rainfall and occurrence of brackish groundwater for irrigation further complicates the crop production issues. In the hyper-arid environment of UAE, integrating trees and shrubs with other farm enterprises could be a useful strategy to increase system’s productivity. Field studies conducted on UAE soils have shown that Acacia ampliceps can fix nitrogen under different salinity levels ranging from 10 to 30 dSm-1, thus supporting the nutrient requirements for the two grasses i.e. Sporobolus arabicus and Paspalum vaginatum. These grasses produced up to 28 tons ha-1yr-1of dry matter. When harvested at 2 m from the ground surface, these trees additionally provided ~ 10 tons ha-1yr-1of foliage. The nitrogen fixation by the Acacia trees increases soil nitrogen to support forages. In the (Sabkha) coastal areas, growing halophytic plants such as Atriplex species can be beneficial due to low annual maintenance costs and their ability to survive high salt contents in the soil. Once the soil improves, non-halophytic trees, shrubs and grasses can also be planted. Until now 76 halophyte species have been identified for the UAE, which include 14 seawater tolerant halophytes, 29 halophytes, 31 semi-halophytes, and two parasitic plants belonging to Chenopodaceae and Zygophyllaceae family. The transformation of these saline lands into productive lands through large-scale adoption of halophytes and salt-tolerant plant species can have a significant impact on the livelihood and food security of rural pastoral communities of the dry regions.