Evaluation of hydrochar-derived modifier and water-soluble fertilizer on saline soil improvement and pasture growth

Abstract

Soil salinization poses a serious threat to crop growth. The selection of appropriate soil modifiers and water-soluble fertilizers for saline soils represents a crucial method for enhancing crop yields. The modifiers and medium-element water-soluble fertilizers were prepared using hydrochar derived from rice straw. Two distinct experiments were designed to study the effect of modifiers and water-soluble fertilizers on saline soils. The first experiment, designated as the “Soil Cultivation Experiment” , sought to investigate the impact of various modifiers on soil quality. The second experiment, designated as the “Method of Field Micro-Area Experiment”, aimed to assess the influence of water-soluble fertilizers on saline soils. The results showed that the application of modifiers and water-soluble fertilizers significantly enhanced comprehensive soil physical and chemical properties, crop growth, soil enzyme activity, and other key indicators in saline and alkaline soils. The optimal dosage of the modifier was 20 g/kg, which reduced the pH value from 8.62 to 8.21 and the decreased alkalinity by 8.26%. Furthermore, their application effectively boosted nutrient levels, including organic matter, and increased soil enzyme activity. The biomass of alfalfa showed enhancements of 63.01% and 20.87% and the biomass of leymus chinensis increased by 29.39% and 9.02% for the two batches, respectively. Notably, the application of water-soluble fertilizer yielded achieved superior results. This study also provided a theoretical basis for their future application in soda saline–alkali soil.