摘要
通过室内培养的方式,研究了不同添加剂量下,不同C/N与灰化碱含量的有机物料对酸性茶园土壤的改良能力。试验结果表明:有机物料的添加可以有效地减少土壤交换性酸、铝饱和度,增加土壤交换性碱基,但是在调节土壤pH能力上并非一定有效。初始阶段,"灰化碱"的释放与有机氮的矿化提高了土壤的pH,随后pH由于硝化作用出现不同程度的下降。C/N高的作物秸秆(小麦和水稻秸秆)能够有效地抑制硝化,使pH下降幅度较小;而C/N低的作物秸秆(花生秸秆和菜籽饼)促进硝化,使pH大幅度下降。最终土壤pH与其C/N呈正相关性(y=0.00343x+4.14,r=0.977),而与其灰化碱含量无关。并且随着秸秆添加剂量的加大,C/N高的作物秸秆最终调剂pH的能力是显著提高的(P<0.05),而C/N低的作物秸秆最终调剂pH的能力没有显著提高(P<0.05)。因此,C/N高的作物秸秆可能更适合土壤酸度的长期调节,与其相关的田间试验需要进一步进行证实。
A laboratory incubation study was conducted to investigate the application of crop residues with different C/N ratios and ash alkalinity content. Each component was added at 3 different rates and the potential to ameliorate soil acidity was assessed. Incorporation of crop residues was an effective method to reduce soil exchangeable acidity, A1 saturation and increase base saturation, but not necessary for soil pH adjustment. The release of alkalinity from residues and the mineralization of organic nitrogen increased soil pH initially, and then decreased due to nitrifications. Various degrees of nitrification were correlated with the C/N ratios of residues. Crop residues with high C/N ratios （i.e. wheat and rice straw） repressed soil nitrification, which resulted in slight pH decrease, whereas crop residues with low C/N ratios （i.e. rapeseed cake and peanut straw） stimulated soil nitrification, and resulted in a sharp decrease in soil pH. Soil pH at the end of incubation was positively correlated with C/N ratios of residues （y = 0.003 43x ＋ 4.14, r = 0.977）. Further, a significant pH increase occurred as the rates of residues increased for residues high in C/N ratio （P〈0.05）, but not for residues low in C/N ratio （P〉0.05）. It is suggested that crop residues high in C/N ratio are preferred to ameliorate soil acidity. A further investigation is needed in the form of long-term field study on amendments variables.
出处
《土壤》
CAS
CSCD
北大核心
2013年第3期430-436,共7页
Soils
基金
国家科技支撑计划项目(2009BADC6B02)
高校省级优秀青年人才基金项目(2012SQRL272)
国家环境保护部公益性行业科研专项(2013467036)资助
关键词
有机物料
酸化
调控
Crop residues, Soil acidity, Amelioration
