Collaborative Research: Stabilized Organic Carbon and Paleoenvironmental Interpretations of Late Quaternary Paleosols

合作研究：稳定有机碳和晚第四纪古土壤的古环境解释

• 批准号: 1226949
• 负责人: Michael Thompson
• 金额: $ 11.74万
• 依托单位: Iowa State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-15 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1226949&HistoricalAwards=false
• 关键词: Collaborative; Research; Stabilized; Organic; Carbon

Collaborative Research: Stabilized Organic Carbon and Paleoenvironmental Interpretations of Late Quaternary PaleosolsMichael Thompson, Iowa State University, EAR-1226949Elmer Bettis III, University of Iowa, EAR-1226412Rolfe Mandel, Kansas University, EAR-1226757Jingdong Mao, Old Dominion University, EAR-1226323ABSTRACTPaleosols are widespread archives of paleoenvironmental information. Many Quaternary paleosols are laterally extensive, readily correlated, and suggestive of periods of regional climatic or geomorphic stability. This grant focuses on organic matter (OM) in paleosols. The objectives of this grant are (1) to identify and rank the importance of mechanisms of OM stabilization at the millennial scale, and (2) to significantly refine paleovegetation reconstructions of midcontinent, Late-Quaternary environments. At five sites in Kansas and Nebraska, OM will be studied in buried paleosols as old as 44.6 ka. These paleosols were chosen (1) to characterize paleosol organic matter in the two most widespread surficial materials in the Midcontinent (alluvium and loess), (2) to compare OM that has witnessed primarily aerated conditions (loess soils) with OM that has been subjected to alternating aerated and saturated condition (alluvial soils); (3) to systematically lengthen the periods in which OM has been buried, giving opportunity for early diagenetic changes to occur; and (4) to capitalize on information available from previous studies.This project will improve understanding of which components of soil organic matter are preserved over millennial time scales and why they are preserved. Such understanding will inform reconstructions of Quaternary paleoenvironments and landscapes that are based on OM-hosted proxies. Of particular interest is the hypothesis that a significant component of stable carbon in paleosols consists of charcoal.By evaluating the significance of charcoal in paleosol OM, the roles that fire can play in carbon storage, landscape evolution, and interpretations of paleoclimate can be elucidated. Because some forms of OM bind together mineral particles, paleosol OM components may regulate the ability of sediments to resist erosion, thus impacting landscape evolution. The research will also help to refine geochemical models that predict the amount of carbon that can be effectively sequestered in soils and provide new insights concerning the long-term stability of terrestrial OM and its impact on global carbon cycles.This project will broaden participation of underrepresented groups in earth sciences through collaboration with colleagues and students at Alabama A&M Univ. AAMU students be invited to join the research team during summer sessions as part of ISU's George Washington Carver Summer Internship program and they will be recruited for graduate studies at Iowa State Univ. and Univ. of Iowa.

合作研究：稳定的有机碳和古环境解释是晚期Quaternary Paleosolsmichael Thompson，爱荷华州立大学，EAR-1226949EL-1226949ELMER BETTIS III，爱荷华大学，EAR-1226412ROFFE MADEL，EAR-1226412ROLFE MANDEL EAR-1226323abtractpaleosols是古环境信息的广泛档案。许多第四纪古质横向广泛，易于相关，并暗示了区域气候或地貌稳定性的时期。这项赠款重点介绍了古溶质中的有机物（OM）。 该赠款的目标是（1）识别和对千禧一代稳定机制的重要性，以及（2）显着完善中大陆，晚期环境的Paleaovegetation重建。在堪萨斯州和内布拉斯加州的五个地点，OM将在埋葬的古质量中进行研究，年龄为44.6 ka。选择这些古溶物（1）以将两种最广泛的表面材料（冲积层和黄土）中的两种最广泛的表面材料（2）表征，以比较已经见证了主要的充气状况（黄土土壤）的OM，而OM与已经历过交替的充气和饱和条件（全弱的土壤）进行了比较； （3）系统地延长了OM被埋葬的时期，从而为早期成岩化变化提供了机会； （4）利用先前研究可用的信息。该项目将在千禧一代尺度上保存土壤有机物的哪些组成部分以及保留它们的原因。这种理解将为基于OM托管代理的第四纪古环境和景观的重建提供信息。特别令人感兴趣的是，假设是古溶质中稳定碳的重要组成部分。通过评估木炭在古溶中的重要性，可以阐明火灾在碳储存，景观演化以及古气候的解释中发挥作用的作用。由于某些形式的OM将矿物颗粒结合在一起，因此古溶OM成分可能调节沉积物抵抗侵蚀的能力，从而影响景观的演变。这项研究还将有助于完善地球化学模型，以预测可以有效地隔离在土壤中的碳量，并提供有关陆地OM长期稳定性及其对全球碳周期的影响的新见解。该项目将通过与Cloceation Alabame and Alabama and Alabama a＆M niv的协作来扩大地球科学群体不足的团体的参与。作为ISU的乔治·华盛顿·卡弗（George Washington Carver）暑期实习计划的一部分，邀请Aamu学生在夏季课程中加入研究团队，他们将在爱荷华州立大学招募研究生学习。和大学。爱荷华州。