Collaborative Research: Detecting Spatial Patterns of Dust Effects on Soils: Testing New Methodology in the Central Great Plains

本项目将利用大平原中部的一个研究区，调查大气尘埃沉降在形成土壤变化的区域空间格局中的作用。 在大平原上，就像在许多其他干旱到半湿润的景观中一样，有地质证据和现代文献证明经常性的区域尘埃输送和沉积。 在全新世，高速率的灰尘沉积在该地区的分散地点产生了不同的黄土沉积。更缓慢沉积的灰尘可能已经被纳入更大面积的土壤剖面中。该项目的关键新内容是利用横跨大平原中部的采样点网络，重点探测表明尘埃输送的区域空间模式。 尘埃沉积速率、粒度和矿物学随距离源的远近而系统地变化。 这些趋势应反映在区域空间格局的土壤形态和矿物学对应的“羽”全新世灰尘分散的主要来源。 将在每个地点对多个土壤剖面进行取样，以量化当地的变异性。 调查人员将从区域采样网络中选择有代表性的土壤，用于更详细地调查土壤发育过程中灰尘增加的矿物学和地球化学证据，该项目将测试可以更广泛地应用于土壤科学基本问题的方法，即受经常性灰尘产生和沉积影响的景观。 沙尘沉降被广泛认为是土壤形成的一个重要过程，但大多数以前的研究没有集中在广泛的区域模式的灰尘对土壤的影响。 这些空间模式是将灰尘影响纳入我们对重要的土壤相关环境问题的理解的关键。 例如，土壤储存有机碳的潜力是预测和减轻人类引起的全球碳循环变化的一个重要问题。 沙尘沉降可能会影响土壤碳储量潜力的区域格局，因为增加的灰尘可以改变土壤性质，强烈影响碳储量。 由于该项目将对一个区域土壤网络进行采样，其结果将直接适用于绘制大区域土壤碳储存潜力。 该项目的结果还将有助于解释埋藏的土壤，这些土壤是过去气候变化的重要指标。

This project will investigate the role of atmospheric dust deposition in creating regional spatial patterns of soil variation, using a study area in the central Great Plains. On the Great Plains, as in many other arid to subhumid landscapes, there is both geologic evidence and modern documentation of recurrent regional dust transport and deposition. During the Holocene, dust deposition at high rates produced distinct loess deposits in scattered localities in this region. More slowly deposited dust may have been incorporated into developing soil profiles over much larger areas. The key new element in this project is the focus on detecting regional spatial patterns indicative of dust transport, using a network of sampling sites across the central Great Plains. Dust deposition rate, grain size, and mineralogy vary systematically with distance from the source. These trends should be reflected in regional spatial patterns of soil morphology and mineralogy corresponding to "plumes" of Holocene dust dispersal from major sources. Multiple soil profiles will be sampled at each site to quantify local variability. From the regional sampling network, the investigators will select representative soils to use in more detailed investigations of the mineralogical and geochemical evidence for dust addition during soil development.This project will test methodology that can be much more broadly applied to a basic problem of soil science, in landscapes affected by recurrent dust production and deposition. Dust deposition is widely recognized as an important process in soil formation, but most previous studies have not focused on broad regional patterns of dust effects on soils. These spatial patterns are the key to incorporating dust effects into our understanding of important soil-related environmental issues. For example, the potential of soils to store organic carbon is an important issue in efforts to predict and mitigate human-induced changes in the global carbon cycle. Dust deposition may affect regional patterns of soil carbon storage potential because the added dust can change soil properties that strongly influence carbon storage. Because this project will sample a regional network of soils, the results will be directly applicable to mapping soil carbon storage potential over a large region. Results of this project will also help interpret buried soils that are important indicators of past climate change.