Tillage, Manure and Gypsum Use in Reclamation of Saline-Sodic Soils

摘要

Soil degradation resulting from soil salinity and sodicityis a major problem under arid and semiaridclimates. Nearly 831 million hectares of land are salt-affected worldwide. Thehigh salt concentration negatively affects soil physical and chemicalproperties as well as soil microbial activity, thus causing a decline in soilproductivity. It has led to the depletion of soil organic carbon, decline inbiomass production, contamination of water resources, and emission ofgreenhouse gases such as CO2 at an accelerated rate. The initialhydration of sodic clays leads to slaking and swelling while continuoushydration results in dispersion of clay particles. Saline and sodic soilsusually suffer from poor physical properties, including high bulk density, lowmacroporosity and aggregate stability. Therefore, management of such soils ischallenging. The fundamental issue of soil quality improvement may in along-term have a aim to restore an earlier state for the required cropproduction purposes or to limit and/or slowing down the further deterioration,in order to reservations the original values and features of the soilproperties. Appropriate tillage is key factor for mitigation of negativeeffect, while application of organic matter through various sources is anotheramelioration strategy for salt-affected soils. These procedures affect soilphysical, chemical and biological properties. Tillage improves aeration andalleviates compaction while organic matter promotes binding soil particles intoaggregates. Present paper present positive aspect of tillage and amendmentaddition (gypsum, farmyard manure, sulfur) on properties of saline-sodic soilsusing available literature.