Vermicompost and deep tillage system better than chemical amendments and
conservative tillage to improve saline-alkaline soils and wheat
productivity
Abstract
Land degradation due to soil salinity and alkalinity is considered a
serious concern in arid ecosystems. Due to arid climate even, normal
soils are converted to saline-alkaline soils. Despite the importance of
conservative tillage in carbon sequestration and improving soil
properties, its effect on saline-alkaline soils even under amendments
application remains unknown. In addition, application of soil
conditioners particularly vermicompost with tillage systems on saline
soil has less attention so far. Therefore, the present study assigned to
explore the combined effects of inorganic (sulfuric acid and gypsum) and
organic (vermicompost) soil amendments and tillage systems (zero,
reduced and deep tillage) on saline-alkaline soil properties and wheat
productivity. Deep tillage with vermicompost application significantly
reduced soil electrical conductivity (EC), exchangeable sodium
percentage (ESP), penetration resistance (PR) and bulk density (BD) and
increased soil hydraulic conductivity (HC), mean weight diameter (MWD)
and aggregation index (AI) compared to control. Deep tillage showed a
significant improvement of saline-sodic soils, despite increasing (SOC)
with zero and reduced tillage. Moreover, vermicompost and sulfuric acid
applications with deep tillage increased wheat grain yield significantly
compared to control. Vermicompost application surpassed chemical
amendments in improving properties of saline-alkaline soils, and
consequently enhanced growth and yield of wheat, providing that using
deep tillage as an appropriate tillage system. Although deep tillage
reduced soil organic carbon, application of vermicompost not only
compensated this reduction but also increased SOC significantly. This
could confirm the importance of combining deep tillage and vermicompost
as an acceptable method in reclaiming such soil environmentally