秸秆生物质炭土地利用的环境效益研究

农田土壤有机碳矿化释放CO2是农业温室气体排放的重要途径,促进土壤碳截获对于减缓全球温室效应具有重要意义。生物质炭具有改良土壤性质、促进土壤团聚体的形成、对土壤微生物生态具有调控作用等特性。因此,生物质炭对增强土壤碳截获能力及减少土壤CO2气体排放可能具有重要作用。采用实验室盆栽的方式,以黑麦草为目标植物,对农业秸秆生物质炭土地利用的环境效益进行了研究。实验结果表明：农业秸秆制生物质炭应用于农田土壤能产生多方面的环境效益。与对照相比,添加1%~4%生物质炭处理的土壤活性有机质质量分数均增加了25%以上,土壤呼吸度降低了23%~50%,同时,添加生物质炭对植物的生长也有促进作用。添加4%秸秆炭的处理的黑麦草生物量增加了68%。此外,秸秆生物质炭的添加对土壤中的养分具有较好的持留功能,与比照相比,添加生物质炭处理的土壤淋出液中氮和磷质量浓度显著降低,说明生物质炭能够有效减少水冲刷造成的氮磷流失,降低农业面源污染。

Environmental benefits of biochar made by agricultural straw when applied to soil

Mineralization of organic carbon and emission of CO2 in agricultural soil are main pathways of greenhouse gas emission.The improvement of soil carbon capture and sequestration has important effect on the reduction of greenhouse effect.Biochar can improve soil character and the formation of soil agglomerates and it also can adjust the microorganism ecology in soil.Environmental benefits of biochar made by agricultural straw applied in soil were studied.The results indicated that straw charcoal might produce a wide range of environmental benefits.On one hand,it had the ability to promote the carbon fixed in the soil and reduce soil respiration,which can effectively mitigate global climate change.In treatment of biochar added,soil respiration reduced 23%-50% and content of active soil organic matter increased above 25% compared with control.On the other hand,biochar played a positive role on promoting plant growth.Biomass in treatment added 4% biochar increased about 68% compared with the control.In addition,biochar can hold nutrients in the soil and reduce nitrogen and phosphorus losses caused by water erosion and agricultural non-point source pollution.