Halophytic Crops as a Solution for Food Security, Land Rehabilitation, and Mitigating Future Water Crises by Utilizing Marginal Quality Waters

Water scarcity poses a significant challenge, especially in arid and semiarid regions of the world. The growing demand for fresh water globally puts additional pressure on both food security and sustainable water use in agriculture. Therefore, it becomes essential to explore alternative water sources such as brackish/saline water or reclaimed domestic water alongside conventional fresh water to meet these needs. Fortunately, there is a selection of plants, including crops, fruits, and ornamental species, that demonstrate remarkable tolerance to high salinity levels and are termed halophytes, or salt-loving plants. These halophytes not only thrive in salty environments but also aid in soil-salt remediation by extracting salts from the soil, thus reducing the burden on freshwater resources that can be redirected for more productive uses. Arid lands, characterized by annual rainfall between 100 and 300 mm and an aridity index (AI) ranging from 0.05 to 0.2 (AI <0.05 for hyper-arid regions), face significant challenges in sustaining agriculture due to limited arable land, a scarcity of fresh water, and hot climatic conditions. Countries rich in oil resources, such as the GCC region, often compensate for water scarcity in agriculture by relying on energy-intensive desalination processes. Simultaneously, in the GCC and other arid regions, water with a higher salt content is employed to cultivate crops that are tolerant to varying salinity levels. This strategy helps conserve freshwater resources, which can then be utilized to grow high-value cash crops, ultimately mitigating water crises. This chapter provides a comprehensive overview of diverse salt-tolerant crops and plants (halophytes) relevant to agriculture, urban landscapes (ornamental species), and the rehabilitation of saline and hypersaline arid lands. The discussion highlights the potential of these halophytes in addressing water scarcity issues and promoting sustainable agricultural practices in challenging environments.