Utilization of sewage sludge to manage saline–alkali soil and increase crop production: Is it safe or not?

Saline-alkali soil has become significant problem for global agriculture and food security as these soils have poor physicochemical conditions and reduce crop production by causing a wide range of physiological and biochemical changes in plants. More than 800 million hectares (Mha) of land throughout the world affected by saline-alkali soil, which accounts for 6% of the world total land area and about 62 Mha or 20% of the world’s irrigated land is affected by saline-alkali soil. Numerous studies on saline-alkali soils have been conducted throughout the years in an attempt to reduce plant productivity losses. Utilizing sewage sludge (SS) is an efficient way to improve saline-alkali soil and its physiochemical properties for plant productivity and improve soil’s health and crop…