基于农业固废资源化利用的土壤改良试验研究

Experimental study on soil modification based on the utilization of agricultural solid waste as resources

为解决西北干旱草原地区黄金矿山生态修复土壤贫瘠、客土短缺等问题,以农业固废玉米秸秆为原料制备的生物质材料为改良剂进行土壤改良及植被恢复试验研究。通过分析改良土壤pH、营养成分、持水保水能力等指标的变化,探究了生物质材料对修复基质的改良机制。以黑麦草、高羊茅、狗牙根为修复植物,验证生物质材料对贫瘠土壤的改良作用。结果表明:生物质材料中含有大量的腐殖酸和黄腐酸,二者可显著降低表土基质的盐碱性,土壤pH值由8.80降至7.39,且随添加比例的增加酸碱度改良效果明显;生物质材料的加入促进了土壤大粒径团聚体的形成,土壤密度显著降低,持水保水能力提高,营养成分、有机质含量均有显著升高;当生物质材料占比为10%~20%时,黑麦草、高羊茅、狗牙根生物量最高,且叶片宽度、植株高度都较优。

In order to solve the problems of poor soil and shortage of guest soil for ecological restoration of gold mines in the arid steppe region of Northwest China,an experimental study on soil modifier vegetation restoration using biomass materials as soil modifier prepared from agricultural solid waste corn straw as raw materials was carried out.By analyzing the changes in pH,nutrient composition,and water retention capacity of modified soil,the modification mecha-nism of biomass materials on the restoration matrix was explored.Ryegrass,tall fescue,and dogtooth root are used as modifiers to verify the modification effect of biomass materials on poor soil.The results showed that biomass materials contain a large amount of humic acid and fulvic acid,which can significantly reduce the saline-alkali property of topsoil matrix,soil pH value decreasing from 8.80 to 7.39,and the pH improving significantly with the increase of the added proportion;the addition of biomass materials promoted the formation of soil aggregates with large particle size,soil bulk density decreased significantly,soil water retention capacity increased,and soil nutrients and organic matter contents increased significantly;the biomass of ryegrass,tall fescue and dogtooth root was the highest when the biomass content was 10%-20%,and the leaf width and plant height were better.