Pedra Filipe, Plaza César, García-Gil Juan Carlos, Polo Alfredo
Laboratório Químico Agrícola Rebelo da Silva, Apartado 3226, 1301-903 Lisbon, Portugal.
Bioresour Technol. 2008 May;99(7):2141-7. doi: 10.1016/j.biortech.2007.05.043. Epub 2007 Jul 10.
The effects of amendment with municipal solid waste compost (MSWC) and sewage sludge (SS) on acid-base properties of soil humic acids (HAs) were investigated. For this purpose, HAs were isolated from MSWC and SS and two different Portuguese soils, one sandy and the other clay loam, either unamended or amended with MSWC or SS at a rate of 60 t ha(-1), and analysed by potentiometric titrations at various ionic strengths (0.01, 0.05, 0.1 and 0.3M) over the pH range from 3.5 to 10.5. All titration data were fitted with the NICA-Donnan model and the variations of model parameters between the various HA samples were discussed. The HAs from MSWC and SS had lower acidic functional group contents and higher proton binding affinities than the control soil HAs. Amending soils with MSWC and SS determined a decrease of acidic functional group contents and an increase on proton binding affinities of soil HAs. These effects were more evident in SS-amended soil HAs than in MSWC-amended soil HAs, and in clay loam soil HA than in sandy soil HA.
研究了添加城市固体废弃物堆肥（MSWC）和污水污泥（SS）对土壤腐殖酸（HAs）酸碱性质的影响。为此，从MSWC和SS以及两种不同的葡萄牙土壤（一种是砂土，另一种是粘壤土）中分离出HAs，这些土壤要么未添加，要么以60 t ha(-1)的速率添加MSWC或SS，并在pH值为3.5至10.5的范围内，于不同离子强度（0.01、0.05、0.1和0.3M）下通过电位滴定法进行分析。所有滴定数据均采用NICA-Donnan模型拟合，并讨论了不同HA样品之间模型参数的变化。与对照土壤HAs相比，来自MSWC和SS的HAs具有较低的酸性官能团含量和较高的质子结合亲和力。用MSWC和SS改良土壤会导致土壤HAs的酸性官能团含量降低，质子结合亲和力增加。这些影响在添加SS的土壤HAs中比在添加MSWC的土壤HAs中更明显，在粘壤土HA中比在砂土HA中更明显。
