Abstract
Coal bio-briquettes that were made with coal, biomass and a desulfurizer are suitable for desulfurization technology and biomass utilization in rural areas of China. Because coal bio-briquette ash included Ca compounds such as gypsum, we investigated the effects of ash application on corn growth and amelioration of soil chemical properties for salt-affected soils in northeastern China. Two types of bio-briquette (BB 1 and BB 2) were made from low-quality coal (sulfur content = 2.1% (BB 1) and 4.1% (BB 2)), corn stem, and calcium hydroxide. Two bio-briquette ashes (BBA 1 and BBA 2) were added to four experimental fields of salt-affected soil at application rates of 0 wt%, 0.5 wt% (1.16 kg/m2), 1.0 wt% (2.32 kg/m2), 2.0 wt% (4.64 kg/m2) and 3.0 wt% (6.96 kg/m2) in three replications. Moreover, ammonia fertilizer was added to all plots, and pig manure as an organic fertilizer was added to two of the test plots. Corn production increased with increased application rate of ash across all test plots. In addition, pH and ESP, Na, CO3 and HCO3 concentration of soil solution decreased with increased application rate of bio-briquette ash. Results suggest that decreased pH and ESP with an associated decrease in Na compounds such as Na2CO3 and NaHCO3 at greater ash application rates contribute towards observed increases in corn production. In conclusion, application of bio-briquette ash derived from low-quality coal could effectively ameliorate salt-affected soils.
