Development of a lateral topographic weathering gradient in temperate forested podzols
Development of a lateral topographic weathering gradient in temperate forested podzols
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温带森林灰化土横向地形风化梯度的发展
DOI：
10.1016/j.geoderma.2023.116677
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发表时间：
2023
期刊：
影响因子：
6.1
通讯作者：
Schreiber, Madeline E.
中科院分区：
文献类型：
--
作者：
Bower, Jennifer A.;Ross, Donald S.;Bailey, Scott W.;Pennino, Amanda M.;Jercinovic, Michael J.;McGuire, Kevin J.;Strahm, Brian D.;Schreiber, Madeline E.
矿物风化是由水、生物、溶液化学和矿物学相互作用驱动的一种重要的成土过程。坡面尺度的水通量模式对土壤矿物风化的影响还不是很清楚，特别是在潮湿的冰后期土壤中，通常含有丰富的风化原生矿物。以前在这些环境中的工作表明了横向水文模式对山坡尺度土壤形成的重要性。在这项研究中，我们假设在美国新罕布夏州怀特山的灰壤中，水文驱动的成壤作用与化学风化之间存在着对应的关系。我们通过量化沿控制侧向水流的基岩的地形和深度的坡度，对近距离、相似年龄的细小颗粒(≤2 mm)中斜长石的消耗量进行了检验，以检验这一假设。沿这一坡度，横向发育的灰壤是由上坡地下水频繁的间歇性冲刷形成的，垂直发育的灰壤是通过特征垂直入渗形成的。我们用传质系数(τ)估算了斜长石结合元素在土壤层上层的耗竭，并通过电子显微镜和微探针分析直接量化了斜长石的损失。元素耗竭在上坡的外侧残积层(E层占优势)灰壤中显著高于下坡的侧积层(B层占优势)和垂直(同时包含E层和B层)灰壤，Na损失的中位数分别为∼74%、∼56%和∼40%。当比较遗传E层时，与垂直发育的灰壤相比，横向发育的灰壤中Na和Al的贫化程度明显更高。微探针分析表明，斜长石的∼74%来自侧向残积灰壤矿藏，而侧向淤积灰土和垂直发育的斜长石分别为∼39%和∼23%。尽管这种强烈的风化作用，斜长石仍然是土壤薄片中第二丰富的矿物。这些发现证实，土壤垂直发育的概念并不能准确地描述地形复杂地区的土壤特征。我们的工作通过识别由当地水文和地形模式塑造的矿物风化中明显的、短尺度的梯度，改善了目前对成壤作用的理解。
Mineral weathering is an important soil-forming process driven by the interplay of water, organisms, solution chemistry, and mineralogy. The influence of hillslope-scale patterns of water flux on mineral weathering in soils is still not well understood, particularly in humid postglacial soils, which commonly harbor abundant weatherable primary minerals. Previous work in these settings showed the importance of lateral hydrologic patterns to hillslope-scale pedogenesis. In this study, we hypothesized that there is a corresponding relationship between hydrologically driven pedogenesis and chemical weathering in podzols in the White Mountains of New Hampshire, USA. We tested this hypothesis by quantifying the depletion of plagioclase in the fine fraction (≤2 mm) of closely spaced, similar-age podzols along a gradient in topography and depth to bedrock that controls lateral water flow. Along this gradient, laterally developed podzols formed through frequent, episodic flushing by upslope groundwater, and vertically developed podzols formed through characteristic vertical infiltration. We estimated the depletion of plagioclase-bound elements within the upper mineral horizons of podzols using mass transfer coefficients (τ) and quantified plagioclase losses directly through electron microscopy and microprobe analysis. Elemental depletion was significantly more pronounced in the upslope lateral eluvial (E horizon-dominant) podzols relative to lateral illuvial (B horizon-dominant) and vertical (containing both E and B horizons) podzols downslope, with median Na losses of ∼74 %, ∼56 %, and ∼40 %, respectively. When comparing genetic E horizons, Na and Al were significantly more depleted in laterally developed podzols relative to vertically developed podzols. Microprobe analysis revealed that ∼74 % of the plagioclase was weathered from the mineral pool of lateral eluvial podzols, compared to ∼39 % and ∼23 % for lateral illuvial podzols and vertically developed podzols, respectively. Despite this intense weathering, plagioclase remains the second most abundant mineral in soil thin sections. These findings confirm that the concept of soil development as occurring vertically does not accurately characterize soils in topographically complex regions. Our work improves the current understanding of pedogenesis by identifying distinct, short-scale gradients in mineral weathering shaped by local patterns of hydrology and topography.
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哈伯德布鲁克垂直和横向灰化作用之间的化学和形态差异
DOI：
--
发表时间：
2015
期刊：
影响因子：
--
作者：
Rebecca R. Bourgault;D. Ross;S. Bailey
通讯作者：
S. Bailey
影响因子：
6.1
作者：
Olivia L. Fraser;S. Bailey;M. Ducey;K. McGuire
通讯作者：
Olivia L. Fraser;S. Bailey;M. Ducey;K. McGuire
气候驱动的化学风化对土壤生产的作用
DOI：
--
发表时间：
2014
期刊：
影响因子：
--
作者：
K. Norton;P. Molnar;F. Schlunegger
通讯作者：
F. Schlunegger
灰化作用的质量平衡分析：以美国东北部为例
DOI：
--
发表时间：
1995
期刊：
影响因子：
--
作者：
J. Jersak;R. Amundson;G. Brimhall
通讯作者：
G. Brimhall
影响因子：
3.7
作者：
Johnson, CE;Driscoll, CT;Likens, GE
通讯作者：
Likens, GE