Curing the earth: A review of anthropogenic soil salinization and plant-based strategies for sustainable mitigation

Abstract

At low concentrations salts are relatively benign, but anthropogenic activities can drive concentrations to levels that impact soil quality, microbial, plant, and animal life. Soil and freshwater salinization are growing issues worldwide that are difficult to manage with conventional treatments. In this review, salt tolerant plants known as halophytes are evaluated for their potential to phytoremediate salinized soils and prevent leaching of salts into surface and ground water. While most plants are sensitive to high concentrations of salt in their growth media, halophytic plants have developed mechanisms to tolerate and thrive in these environments. Some plants exclude salts at the roots, others sequester salts in their central vacuole, while others secrete salts through specialized salt glands on their leaf surfaces. The extraction of salts from soil by both plants that sequester or secrete salts are reviewed as well as implementation strategies that could drive economic feasibility. Further, phytoremediation of salinized soils is considered in the context of a changing climate.