施用土壤改良剂对坡耕地烤烟土壤有机碳及其组分的影响

Effects of Soil Modifiers on Soil Organic Carbon and Its Components in Sloping Farmland Soil of Flue-cured Tobacco

以云南省玉溪市红塔区坡耕地烤烟土壤为研究对象,选择生物质炭、木质素、聚丙烯酰胺和秸秆4种土壤改良剂,研究施用不同土壤改良剂后土壤各层有机碳及其组分含量的变化特征。结果表明:坡耕地烤烟土壤有机碳及其组分含量不同生育期表现为成熟期<现蕾期<旺长期,不同土层表现为5~10 cm>0~5 cm>10~20 cm,其中以添加高量生物质炭处理(0.6%~47.0%)和高量秸秆处理(1.3%~38.2%)提升效果较为显著;施用4种土壤改良剂在一定程度上均可提高土壤全氮和全磷含量,其中以添加高量秸秆处理最为显著,全氮、全磷含量分别提高15.0%~32.8%、37.6%~40.2%;各处理土壤C︰N在5.07~8.67,C︰P在3.91~6.12,N︰P在0.34~1.00;土壤全氮与全磷、有机碳含量之间分别存在显著(P<0.05)和极显著(P<0.01)正相关关系,有机碳各组分间呈极显著正相关关系(P<0.01);土层深度、生育期和土壤改良剂种类对土壤有机碳组分的影响均极显著(P<0.01)。添加生物质炭和秸秆对滇中红壤丘陵区植烟土壤有机碳及其各组分含量、土壤养分的生态化学计量特征的提升效果更佳,尤其以添加0.06 kg/m2生物质炭和0.5 kg/m2秸秆效果较佳。

In this study,the sloping farmland soil of flue-cured tobacco was taken as the study object in Hongta District,Yuxi City,Yunnan Province,and four soil amendments including biochar,lignin,polyacrylamide and straw were selected to study their effects on soil organic carbon(SOC)and its components in different soil layers.The results show that the contents of SOC and its components in different growth stages of tobacco are in the order of mature stage<emerging stage<flourishing stage,and the contents of SOC and its components in different soil layers are in the order of 5-10 cm>0-5 cm>10-20 cm.The effects of adding high biochar(0.6%-47.0%)and straw(1.3%-38.2%)are more significant.Application of the above amendments can increase soil total nitrogen and total phosphorus concentrations to a certain extent,and the high amount of straw are the most significant(15.0%-32.8%and 37.6%-40.2%,respectively).The ratios of C︰N,C︰P and N︰P of each treatment are in the range of 5.07-8.67,3.91-6.12 and 0.34-1.00,respectively.Soil total nitrogen has significant positive correlation with soil total phosphorus(P<0.05)and SOC(P<0.01),respectively.There are extremely significant positive correlations(P<0.01)among SOC components.Soil depth,growth period and soil conditioner type have extremely significant effects on SOC components(P<0.01).The addition of biochar and straw have better effects on the improvement of SOC and its components as well as the ecological stoichiometric characteristics of soil nutrients,and in particular,the effects of adding 0.06 kg/m2 biochar and 0.5 kg/m2 straw are better.