Comparison of two methods for the isolation of phytolith occluded carbon from plant material
Comparison of two methods for the isolation of phytolith occluded carbon from plant material
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DOI：
10.1007/s11104-013-1847-1
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发表时间：
2014-01-01
期刊：
影响因子：
4.9
通讯作者：
Sullivan, Leigh A.
中科院分区：
文献类型：
--
作者：
Parr, Jeffrey F.;Sullivan, Leigh A.
植物岩遮挡碳（PhytOC）对同位素研究、沉积物定年以及碳的捕获和储存都有重要意义。许多方法已被用于从植物材料中分离植物岩；然而，当采用不同的方法确定植物碳含量时，存在很大的差异。在这项研究中，我们研究了用于量化植物碳的两种主要方法的效用。这些方法是：(1)微波消解- Walkley-Black消解，(2)H2SO4/H2O2。方法(1)获得的PhytOC值比方法(2)获得的PhytOC值高50倍以上。扫描电镜检查表明，差异可能是由于方法(2)使植物岩破碎，允许酸和过氧化物的PhytOC消耗。这些结果表明，对于这里分析的样品：1]改进的微波方法可以测量总PhytOC， 2] H2SO4/H2O2方法可以测量紧密堆积的二氧化硅基质中的PhytOC， 3]保留在植岩腔中的PhytOC可以通过用1]减去2]来计算。在这里分析的样品中，大部分植物碳都存在于植物岩腔中。
Phytolith occluded carbon (PhytOC) is of interest for isotope studies, dating of sediments and the capture and storage of carbon. Many methodologies have been used for the isolation of phytoliths from plant material; however, there are wide disparities in the PhytOC contents when determined by different methodologies. In this study we examine the utility of the two main methods used for quantifying PhytOC.These methods are: (1) a microwave digestion followed by a Walkley-Black digestion, and (2) H2SO4/H2O2.Method (1) produced PhytOC values over 50 times higher than those acquired by method (2). SEM examination indicated that the differences were likely due to shattering of the phytoliths by method (2) allowing consumption by the acid and peroxide of PhytOC .These results indicate that for the samples analysed here: 1] the modified microwave method allowed the total PhytOC to be measured, 2] the H2SO4/H2O2 method allowed the PhytOC within the tightly packed silica matrix to be measured, and 3] the PhytOC retained within the phytolith cavities could possibly be calculated by subtracting 2] from 1]. For the samples analysed here most of the PhytOC resided in the phytolith cavities.