外源硅酸钙对棕壤基础呼吸和碳酸钙含量的影响

Impacts of calcium silicate addition on brown earth basal respiration and calcium carbonate content

采用室内模拟培养的方法,研究了添加硅酸钙对棕壤基础呼吸和碳酸钙含量的影响,为土壤固碳的技术选择提供理论依据。试验设硅酸钙添加量0%、1%、2%、4%和6%5个处理。结果表明,外源硅酸钙在培养前期显著抑制土壤呼吸,其抑制程度随着硅酸钙添加量的增加而增加,平均抑制率为5%(1%处理)～12%(6%处理);整个培养期间,添加硅酸钙处理的土壤碳酸钙含量较对照显著增加,且随着添加量的增加,土壤碳酸钙含量的平均增幅从83%(1%处理)上升到398%(6%处理);土壤呼吸强度和碳酸钙含量之间符合y=Ae-Bx的指数相关关系。上述结果表明,施用硅酸钙通过促进次生碳酸盐的形成从而缓解土壤CO2释放,起到固碳减排的作用。

Impacts of exogenous calcium silicate addition on brown earth basal respiration and calcium carbonate content were investigated through an incubation experiment.The treatments included calcium carbonate addition rates of 0%,1%,2%,4% and 6%.Results showed that calcium silicate addition significantly decreased soil respiration during the early incubation,and the mean inhibition rates increased from 5% in 1% treatment to 12% in 6% treatment.Across the incubation,calcium silicate addition significantly increased soil calcium carbonate content,and the increase magnitude increased from 83% in 1% treatment to 398% in 6% treatment.Soil respiration（y）and calcium silicate content（x）showed the significant relationship of y=Ae-Bx.The results demonstrate that calcium carbonate addition could mitigate soil CO2 emission by promoting formation of soil secondary carbonate.