The Impacts of Salt Affected Soil on Soil and Plant Growth and Management Options with Organic and Inorganic Amendments A: Review

Abstract

Globally, 833 million ha of soils are salt-affected. Approximately 20% of the world’s cultivated lands and 33% of irrigated lands are salt affected. Soil salinization is spreading at the rate of 1–2 million ha year- ¹ globally affecting a significant portion of crop production and making land unsuitable for cultivation. Salinity problems occur under all climatic conditions and can result from both natural and human-induced actions. Generally speaking, saline soils occur in arid and semi-arid regions where rainfall is insufficient to meet the water requirements of the crops, and leach mineral salts out of the root-zone. Salt-affected soils are characterized by the presence of sodium, calcium, magnesium, chlorides, sulfates, carbonates, and bicarbonates at elevated concentrations. However, based on sodium ion and salt concentration, salt-affected soils are categorized into saline, sodic, and saline–sodic soil. Soil salinity is a major problem which can reduce soil microbial community, enzymatic activity, respiration rate of soil, and the bacteria growth of the soils. Salinity negatively influences almost all plant processes including plant growth and plant structure, through biochemical and physical disturbances, ionic imbalance and toxicity, nutrient deficiencies, and osmotic and oxidative stresses. One of the primary effects of salt-affected soil on grain yield is reduced water availability. High salt concentrations in the soil create an osmotic imbalance, making it difficult for plants to absorb water. Soil amendments that have been studied for the reclamation of salt-affected and acid sulfate soils can be divided into two main categories, namely, inorganic and organic amendments. Gypsum, iron sulfate chloride, and sulfuric acid are the widely applied inorganic soil amendment agents having proven reclamation potential for salt-affected soils. Whereas, organic amendments like organic matter, biochar, compost, vermicompost and bio-fertilizers application is anther options for reclamation of salt affected soils.

Keywords: Amendments, gypsum, salt affected, sodium, soil

DOI: 10.7176/JNSR/14-10-02

Publication date:July 31^st 2023