生物质炭在我国蔬菜地应用的研究现状与展望

Research progress and prospects on the biochar's application in Chinese vegetable field

生物质炭是生物质在限氧环境中经过热化学转化产生的固体物质,它在土壤改良、污染土壤修复和碳封存等方面具有广阔的应用前景。针对我国蔬菜地面临土壤酸化、土壤次生盐渍化、面源污染和土壤重金属污染等问题,通过查阅和汇总生物质炭在我国蔬菜地的应用文献,总结和分析了生物质炭在我国蔬菜地的应用现状,深入挖掘其在影响蔬菜地土壤理化性质、温室气体排放、面源污染和重金属迁移等方面的效应及其影响机制。研究表明,生物质炭可提高土壤阳离子交换量、增加土壤中含氧官能团的数量、减小土壤容重等、从而减缓养分的流失,改善土壤理化性质,促进蔬菜增产;生物质炭可减弱重金属在土壤中的生物有效性和可迁移性,钝化其在土壤中的迁移。然而,不同制备工艺的生物质炭性质差异较大;生物质炭在不同区域不同蔬菜地土壤应用时出现结果不一致;缺乏生物质炭的负面效应报道等问题。因此,今后的研究方向应在蔬菜地进行区域间生物质炭的横向对比研究;将短期与长期蔬菜地定位试验相结合进行纵向比较研究;降低生物质炭的成本、识别其潜在风险,为推广生物质炭在我国蔬菜生产领域的应用、建立可持续农业发展模式具有重要意义。

Biochar is the solid material produced through thermochemical converting biomass under the circumstance of limiting oxygen. It was found that biochar showing great potential in soil improvement, contaminated soil remediation and carbon sequestration. The issues of soil acidity, soil secondary salinization, non-point source pollution and heavy metal pollution presenting in vegetable field need to be addressed urgently in China. The research progress of biochar application in the vegetable field in recent years was reviewed by consulting and summarizing lots of related literatures. Furthermore, the mechanisms that biochar＇s functions on ameliorating soil physical and chemical properties, decreasing the N20 emission, dismissing the non-point source pollution, and fixing the heavy metal in the soil were discussed. The results showed that biochar could increase soil cation exchange capacities, enhance the quantities of oxygen-containing functional groups, decrease soil bulk density and so on to slow down the nutrients loss, improve soil properties and promote vegetable yield. Biochar could weaken the bio-availability and transferability, so as to inactivate the migration of heavy metals in the soil. However, the difference existed between the biochar samples under different pyrolysis technologies. The results were inconsistent when applied biochar into different vegetable soils in different areas. The negative effects that biochar brought were lack of reported. The review also prospected the biochar＇s research orientations in future. The horizontal comparison of different biochar samples application on the similar area is suggested to be studied. The short-term and long-term studies on biochar samples application in different areas are suggested to be consistently carried out. The biochar＇s cost is expected to be reduced and its potential risks should be confirmed. The review is of significance of successful inputting bioehar into the Chinese vegetable field and establishing the sustainable agriculture mode.