The impact of soil water content and water temperature on wet aggregate stability. What answer do you want
The impact of soil water content and water temperature on wet aggregate stability. What answer do you want
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土壤含水量和水温对湿团聚体稳定性的影响
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
N. Prakongkep
中科院分区：
文献类型：
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作者：
N. Blair;R. Gilkes;N. Prakongkep
通过浸泡湿筛测定的湿团聚体稳定性通常被用来衡量土壤团聚体的稳定性。多年来，不同的研究人员使用了各种方法，具有广泛的筛子大小、振幅、循环、筛分时间和预干燥方法。筛分前最常见的干燥措施是风干，但干燥后的土壤水分通常不会被说明，也往往不会被测定。根据土壤质地、粘土矿物学和干燥时的空气温度，这些水分含量可能会有所不同。本试验研究了湿筛前不同温度下干燥后的土壤含水率和筛水温度对三种不同土壤类型平均重量直径(MWD)结果的影响。干燥温度对土壤含水量的影响尤其是对高粘粒土壤，这也影响了MWD结果，干燥温度越低，土壤水分含量越高，粘粒含量越高，土壤MWD越大。粘土含量最高且以蒙脱石粘土矿物学为主的土壤，在15℃干燥后的相对分子质量密度是25℃干燥后的5倍以上。砂壤土的结果没有明显差异，因为在整个干燥温度范围内土壤水分含量几乎没有差异。对于不同土壤类型的土壤，筛水温度对MWD结果也有显著影响。这很可能是由于粘结剂在土壤中的不同溶解度造成的。除非对干燥温度和筛分过程中的水温进行标准化，否则随钻测量结果可能会有很大的不同。条件的选择会对结果产生明显的偏差。
Wet aggregate stability determined by immersion wet sieving is commonly used as a measure of the stability of soil aggregates. Over the years different researchers have used a variety of methods with a wide range of sieve sizes, amplitudes, cycles, sieving times and pre-drying methods. The most common drying measurement prior to sieving is air drying but the soil water content after drying is generally not stated and often not determined. This water content can vary depending on soil texture, clay mineralogy and the air temperature at drying. This experiment studied the impact of soil water content following drying at different temperatures prior to wet sieving, and on the temperature of the sieving water, on the mean weight diameter (MWD) results obtained for three different soil types. The drying temperature affected the resulting soil water content particularly for the high clay soils and this also influenced the MWD results, with the lower drying temperature and higher soil water content resulting in a greater MWD in the soils with higher clay contents. The soil with the highest clay content and predominantly montmorillinite clay mineralogy had a MWD following drying at 15 o C more than five times greater than its MWD after drying at 25 o C. The results for the sandy loam soil were not significantly different as there was little difference in the soil water content across the range of drying temperatures. The temperature of the sieving water also significantly affected the MWD results for all soils with different soil types being affected differently. This is likely to be because of the different solubilities of binding agents within the soils. MWD results can vary significantly unless drying temperatures and the temperature of the water during sieving are standardized. The choice of conditions can significantly bias results.