A SCALED SORPTION MODEL VALIDATED AT THE COLUMN SCALE TO PREDICT CADMIUM CONTENTS IN A SPATIALLY VARIABLE FIELD SOIL
A SCALED SORPTION MODEL VALIDATED AT THE COLUMN SCALE TO PREDICT CADMIUM CONTENTS IN A SPATIALLY VARIABLE FIELD SOIL
复制标题
在柱尺度上验证的比例吸附模型可预测空间变化的田间土壤中的镉含量
DOI：
--
复制
发表时间：
1992
期刊：
影响因子：
--
通讯作者：
S. van der Zee
中科院分区：
文献类型：
--
作者：
A. Boekhold;S. van der Zee
镉的吸附与扩展Freundlich方程，占明确的pH值和有机质含量的影响。这个缩放的吸附模型的参数估计使用批量实验与土壤取自耕地。吸附模型解释了不同的pH值和有机质含量从同一领域的两个土壤样品之间的吸附差异。为了验证吸附模型的预测，镉在土壤中的迁移模型。溶质突破的预测是在良好的协议与测量，使用吸附参数值，来自使用相同的背景电解质浓度的批量实验。利用土壤溶液pH值、有机碳含量和Cd浓度的实测值，利用验证的吸附模型预测了田间沿着样带土壤Cd总含量。虽然这些参数的空间变异性是不同的，不相同的土壤中的总镉含量的空间变异性，模型预测结果显示出良好的一致性与观察到的空间格局。土壤pH值和有机质含量的空间变异性是造成土壤Cd含量异质性的重要因素。缩放的吸附模型描述镉吸附以及在两个批次的实验，列规模的实验，并在现场规模，当所有（规模依赖）相关的过程被考虑在内。
Sorption of Cd is described with an extended Freundlich equation, that accounts explicitly for effects of pH and organic matter content. Parameters for this scaled sorption model were estimated using batch experiments with soil taken from an arable field. The sorption model explained differences in sorption between two soil samples from the same field that differed in pH and organic matter content. For validation of the sorption model predictions, a transport model was developed for cadmium in soil. Predictions of solute breakthrough were made that were in good agreement with measurements, using sorption parameter values that were derived from batch experiments that used the same background electrolyte concentration. With the validated sorption model total soil Cd contents along a transect in the field were predicted using measured values of pH, organic carbon content, and Cd concentration in soil solution. Although spatial variability of these parameters is distinct and not identical to the spatial variability of the total Cd content of the soil, model predictions showed good agreement with the observed spatial pattern. Spatial variability of pH and of organic matter content appeared to be an important factor which explained a large proportion of the heterogeneity of Cd contents in this soil. The scaled sorption model described Cd sorption well in both batch experiments, column scale experiments, and at the field scale, when all (scale dependent) relevant processes were taken into account.