摘要
大气氮沉降增加是草地土壤酸化的主要原因。土壤酸缓冲性能作为评估土壤酸化的重要指标,对氮输入的响应受到降水与其他限制养分含量的影响。本研究以我国北方温带弃耕草地氮、磷、水添加试验13年后的土壤为对象,利用二次多项式模型拟合酸滴定曲线,计算了土壤酸缓冲容量(ABC)以及以pH 5.0和4.0为参比的土壤酸中和容量(ANC)。结果表明:不增水处理下,单独加氮和同时添加氮磷均显著降低土壤pH,降低以pH 5.0和4.0为参比时的酸中和容量(ANCpH5.0和ANCpH4.0);单独加磷对土壤pH、ANCpH5.0和ANCpH4.0均无显著影响。增水处理下,加氮及加氮磷显著降低土壤pH、ANCpH5.0和ANCpH4.0;加磷显著降低土壤pH,但增加了ANCpH4.0,而对ANCpH5.0无显著影响。与不增水处理相比,增水处理对土壤pH、酸中和容量均具有显著的正效应。对于初始pH值不同的土壤,采用土壤酸中和容量比酸缓冲容量能更好地指示土壤抗酸化能力。
Increasing nitrogen(N) deposition results in soil acidification in grasslands. Acid buffering capacity of soil is a critical index evaluating soil acidification, the response of which to N input is regulated by precipitation and concentration of other limiting elements. To explore the responses of soil acidification to N, phosphorus(P), and water inputs, we conducted a 13-year field experiment in an old-field grassland and calculated the acid buffering capacity(ABC) and acid neutralizing capacity(ANC) at the reference of pH=5.0(ANCpH5.0) and 4.0(ANCpH4.0), using quadratic curve fitting model. The results showed that, without water addition, single N addition or combined with P addition significantly decreased soil pH, ANCpH5.0 and ANCpH4.0, whereas single P addition had no significant effect on soil pH, ANCpH5.0 or ANCpH4.0. With water addition, the addition of N or combined with P decreased soil pH, ANCpH5.0 and ANCpH4.0, whereas P addition decreased soil pH, increased ANCpH4.0, without effect on ANCpH5.0. In contrast with treatments without water addition, water addition had positive effects on soil pH, ANCpH5.0 and ANCpH4.0. For soils with different initial soil pH values, it was better to select ANC rather than ABC as an index to evaluate soil anti-acidification capacity.
作者
孟亚妮
李天鹏
施展
蔡江平
徐柱文
姜勇
MENG Ya-ni;LI Tian-peng;SHI Zhan;CAI Jiang-ping;XU Zhu-wen;JIANG Yong(Institute of Applied Ecology,Chinese Academy of Sciences,Shenyang 110016,China;University of Chinese Academy of Sciences,Beijing 100049,China;School of Ecology and Environment,Inner Mongolia University,Huhhot 010021,China)
出处
《应用生态学报》
CAS
CSCD
北大核心
2020年第5期1579-1586,共8页
Chinese Journal of Applied Ecology
基金
国家自然科学基金项目(31870441)
国家重点研发计划项目(2016YFC0500707)资助。
关键词
土壤酸化
土壤酸缓冲性能
酸滴定曲线
养分平衡
soil acidification
soil acid buffering capacity
acid titration curve
nutrient balance
