吕晓菡 章明奎 严建立

摘要：为了解黏土矿物改良剂在新垦耕地地力提升中的作用，选择膨润土、高岭石、沸石和硅藻土4种黏土矿物，在添加量为10%的条件下，采用培养试验研究其对有机肥料矿化及土壤有机碳积累的影响。结果表明，与对照比较，添加黏土矿物可明显增加土壤有机碳的积累，其效果由强到弱为膨润土、高岭石、硅藻土、沸石;团聚体分析和重液分组结果表明，添加黏土矿物可显著增加土壤水稳定性团聚体数量，促进矿物结合态有机碳的形成。研究认为，黏土矿物增加有机碳稳定性是其促进土壤有机碳积累的主要原因。关键词：黏土矿物;有机碳积累;新垦耕地;土壤团聚体;砂壤土

中图分类号：S158.5文献标志码：A论文编号：cjas20190700137

Effects of Clay Mineral Amendments on Soil Organic Carbon Accumulation in Newly Reclaimed Sandy Loam Farmland

LV Xiaohan1，ZHANG Mingkui2，YAN Jianli1

（1Hangzhou Academy of Agricultural Sciences，Hangzhou 310024，Zhejiang，China;

2College of Environmental and Resource Sciences，Zhejiang University，Hangzhou 310058，Zhejiang，China）

Abstract：To understand the role of clay mineral amendments in improving the soil fertility of newly reclaimed farmland，four clay minerals，bentonite，kaolinite，zeolite and diatomite，were selected for testing their effects on mineralization of organic fertilizers and accumulation of soil organic carbon by incubation experiments with 10% addition of the amendments. The results showed that the addition of clay minerals could significantly increase the accumulation of soil organic carbon as compared with the control，and the effect decreased in the order of bentonite> kaolinite> diatomite> zeolite. Aggregate measurement and heavy liquid fractionation showed that the addition of clay minerals could significantly increase the amount of water-stable aggregates in the soils and promote the formation of mineral-bound organic carbon. In general，clay minerals could increase the stability of organic carbon，which is the main reason for increasing organic carbon accumulation in the soils.

Keywords：Clay Minerals;Organic Carbon Accumulation;Newly Cultivated Farmland;Soil Aggregates;Sandy Loam

0引言

有機质是评估土壤质量的重要指标，其含量高低可直接影响土壤物理、化学和生物学性状，因此提升土壤有机质一直是耕地地力培育的重点和核心「1-3]。土壤有机质提升的农艺措施主要包括增施有机肥、种植绿肥、秸秆还田、粮肥轮作/间作及用地养地相结合[3-8]。但众多的田间试验表明[7-11]，农艺措施对不同土壤有机质的提升效果有很大的差异，即使培肥多年，砂质和砂壤质农田土壤的有机质含量常常停留在较低的水平，其与这些土壤缺乏无机胶体、有机质稳定性较低有关[12-13]。因此，要有效提升砂质或砂壤质土壤的有机质，必须改变土壤的固有性状，增强土壤对有机质的保蓄能力。黏土矿物是自然界普遍存在的物质，来源广泛，具有较大的比表面积和较强的吸附能力，近年来已被用作土壤改良剂，改良土壤结构和钝化土壤中的重金属[14]。黏土矿……