Gypsum and pressmud amelioration improve soil organic carbon storage and stability in sodic agroecosystems

Abstract

Salinity-induced land degradation poses a threat to environment and food production globally. Farmers' participatory research was carried out to assess the potential of gypsum (Gyp) and pressmud (PM) in alleviating the sodicity stress, and improvement in soil organic carbon (SOC) pools and its stability in the Trans Indo-Gangetic Plains of India. Intensive rice-wheat cultivation using alkali water increased soil pH, exchangeable sodium percentage (ESP), and bulk density (BD) causing a net depletion in SOC. Gypsum (supplies soluble Ca 2+ ) and pressmud (mobilizes native CaCO 3 ) mediated amelioration (Gyp + PM) significantly decreased soil sodification and compaction, and improved total organic carbon (TOC; 32%-64%) over the unamended control. Higher left-over C for SOC stabilization, crop biomass, and rhizodeposition returned through Gyp + PM significantly improved SOC pools and C sequestration culminating in $25% yield superiority over the unamended control.Within SOC pools, highest proportion was equally retained in very labile and nonlabile C pools. On average, the passive pool contained $45% of TOC; albeit to a greater contribution through PM followed by Gyp + PM and Gyp. Rice-wheat system yield (RWSY) was positively correlated with SOC pools and indices while negatively correlated with soil pH, ESP, BD, CaCO 3, and recalcitrant index. Multiple regression analysis showed stratification ratio, CaCO 3 , sensitivity index, and BD as key variables for yield prediction under the existing levels of soil sodicity. The key insights suggest ecosystem-based approach using Gyp + PM in restoring the degraded lands, enhancing crop resilience and system (SOC enrichment and storage) stability, and achieving UN-Sustainable Development Goals related to food security and land degradation neutrality.

Changes in soil microbial biomass and organic C pools improve the sustainability of perennial grass and legume system under organic nutrient management

“…Conversely, the passive pool has a long residence time because of physical and biochemical protection, making it resistant to microbial actions (Zimmermann et al, 2007;Weil et al, 2017;Datta et al, 2018). Previous studies reported the effect of the cropping system on the distribution of active and passive pools in soils of subtropic (Chaudhary et al, 2017;Yadav et al, 2017Yadav et al, , 2019Anantha et al, 2020;Babu et al, 2020;Basak et al, 2021a), arid (Moharana et al, 2017), and semi-arid (Srinivasarao et al, 2013(Srinivasarao et al, , 2016Mitran et al, 2018;Basak et al, 2021b) regions. The application of organic fertilizers is also reported to improve the yield of grain crops through their influence on SOC and associated soil properties (Mandal et al, 2007).…”

Phenotypic Correlations Between Linear Traits and Growth Curves of Holstein Calves

“…Many agricultural amendments [e.g., rice (Oryza sativa) straw, press mud (residue from sugarcane juice filtration), cow manure, combined organic residues, biochar, beneficial microorganisms, and phytohormones] have also been applied with gypsum to improve sodium removing, salt-leaching efficiency, soil biological properties, reclaim degraded lands, and crop yield (Kilpatrick, 2012;Schultz et al, 2017;Yamika et al, 2018;Ahmed et al, 2020;Basak et al, 2021;Bello et al, 2021;Rezapour et al, 2021;Yahya et al, 2022;Xu et al, 2023). Zhao et al (2019) studied buried layers of maize straw (6, 12, and 18 Mg ha -1 )…”

Assessing soil quality for rehabilitation of salt-affected agroecosystem: A comprehensive review

“…Deficiency of Ca and excess of Na affect K nutrition; the toxic appearance of HCO 3 − and CO 3 2in alkali soil also decreases the solubility and availability of Zn and Fe. Many sodic areas also exhibit severe soil erosion, which promotes the loss of soil organic matter (Wong et al, 2010;Datta et al, 2019;Deb et al, 2021;Basak et al, 2021b). The extended periods of submergence because of poor soil permeability also affect soil biological properties (Wong et al, 2010).…”