Ameliorative Effects and Soil Carbon Sequestration Potential of Organic
and In-Organic Amendments in Salt-Affected Soils in A Semi-Arid Region
of Asia
Abstract
Soil salinity is a big concern and main factor which limit crop
productivity. Salt-affected soils can be reclaimed and used for crop
production as well as atmospheric carbon sink. In this study, gypsum
(G), organic amendments and their combinations were used to remediate
marginally salt-affected soils and increasing carbon stocks in three
areas (Dijkot, Uchkera and Jhang). Gypsum along with farmyard manure
(FYM), poultry manure (PM) and green manure (GM) were used in this
study. Except control, treatment 1 received 100% soil gypsum
requirement (SGR), all other 3 treatments received 50% SGR and equal
amounts of FYM, PM and GM, respectively. A 45 day’s incubation study
comprising 0-, 15-, 30- and 45-days intervals resulted that 45 days
interval was more effective in remediation than others. All the
amendments effectively reclaimed the salt-affected soils and increased
soil carbon stocks by increasing carbon sequestration rate through
reduction in soil pH (up to 19%), electrical conductivity (EC) (up to
28%) and sodium adsorption ratio (SAR) (up to 71.55%). While cation
exchange capacity (CEC) (up to 39%), soil organic matter (SOM) (up to
65%), and total nitrogen (TN) (up to 96%) was increased. SOM increase
and carbon sequestration was best seen (62%- or 12.59-tons ha-1) in
50% G and FYM application as compared to control (4.45-ton ha-1) in
S-1. Results obtained helps in concluding that G and its combinations
with organic amendments can effectively reduce the salt concentration in
salt-affected soils and helps in organic matter build-up to support crop
production and carbon sequestration.