南京地区水稻土中固定态铵与伊利石的相关性

本文以南京地区长城岗和泉水两个水稻土剖面为研究对象,在利用Silva-Bremner法测定土壤全样和3个粒级(黏粒、粉粒和细砂粒)的固定态铵含量、利用X-射线衍射仪测定矿物成分的基础上,讨论了固定态铵含量与粒级以及矿物种类的关系.结果认为,两个剖面在以下几个方面具有共性:①在黏粒、粉粒和细砂粒3个粒级中,黏粘粒含量与固定态铵含量的关系最为密切,相关系数分别为0.68和0.64;②在黏粒中的伊利石、高岭石和蒙脱石3种主要矿物中,伊利石含量与固定态铵含量相关性最好,相关系数分别为0.50和0.49;⑨对于全样来说,其中的伊利石含量与同定态铵含量呈极显著正相关,相关系数分别为0.68和0.66.这些数据充分说明,伊利石是南京地区水稻土中固定态铵赋存的最主要载体.

Correlation between fixed ammonium and illite in paddy soil, Nanjing region

In this study, the contents of fixed ammonium (FA) and mineral components in three different particle sizes (clay, silt and fine sand) and bulk samples from Changchenggang and Quanshui profiles in Nanjing region were analyzed by Silva-Bremner method while clay minerals were measured by X-ray diffraction, then the relationship between FA content and particle content, as well as mineral kind were discussed. The results showed that: ①among the three particle sizes, clay content had the closest correlation with FA content with the correlation coefficients of 0.68 and 0.64 for two profiles respectively. ②for three minerals (illite, kaolinite and montmorillonite), which were dominant in clay particles, illite content had the closest correlation with FA content with the correlation coefficients of 0.50 and 0.49 respectively. ③in the bulk samples, illite content had the most significantly positive correlation with FA content with the correlation coefficients of 0.68 and 0.66 respectively. These results indicated that illite might be one of the most important carriers for the storage of FA in paddy soil of Nanjing region.