Combined Application of Desulfurization Gypsum and Biochar for Improving Saline-Alkali Soils: A Strategy to Improve Newly Reclaimed Cropland in Coastal Mudflats

This study investigated the effects of combined (mixed) application desulfurization gypsum and biochar on crop growth soil properties in saline-alkali soils coastal mudflats through indoor pot experiments eight experimental ameliorant treatments. Among them, CK was control newly reclaimed cropland area with no added ameliorator, treatment A applied alone, F while treatments B, C, D, E were set as a combination different ratios, G local multi-year improved farmland ameliorator. Additionally, an evaluation index system established for evaluating improvement cropland. Finally, effect evaluated by assessing physical chemical indicators, well nutrient indicators. Based results, following conclusions drawn: (1) Desulfurization significantly physicochemical properties. Both single mixed increased Ca2+, SO42−, Mg2+ contents reduced pH, sodium adsorption ratio, bulk density. density water-soluble K+, field capacity (water-holding capacity), available phosphorus, potassium, organic matter contents. (2) demonstrated effectiveness promoting growth, where fresh weight, dry plant height, leaf peanut higher than those G. Treatment (desulfurization 100 g/kg) most effective treatment, terms improving weight peanut. C 75 g/kg, 20 had significant height area. (3) After 60 days planting, each ranked > B D CK. The gypsum–biochar alone best effect, followed alone.