Collaborative Research: Lateral weathering gradients typify critical zone architecture in glaciated catchments

合作研究：横向风化梯度是冰川流域关键区结构的典型

• 批准号: 1643415
• 负责人: Donald Ross
• 金额: $ 18.92万
• 依托单位: University of Vermont & State Agricultural College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1643415&HistoricalAwards=false
• 关键词: Collaborative; Research; Lateral; weathering; gradients

The thin skin of soil on Planet Earth is what makes life possible. The interactions of water and rock, or mineral weathering, are responsible for the development of the soil that sustains life and regulates water quality and flow. As such, mineral weathering is a critical natural service that provides nutrients required for plant growth and controls the cycling of nutrients through the environment and their transport to downstream rivers, lakes, estuaries, and the ocean. In this study, mountainous areas of the northeastern United States provide a natural laboratory to examine processes and rates of mineral weathering where soils are relatively young (less than 10,000 years) and bedrock is often shallow, providing spatial gradients of mineral depletion and accumulation across the landscape. This region with young soils supports forests in some of the most densely forested states in the country and is the source of the major rivers of the northeast, providing major metropolitan areas downstream with abundant, clean water. These forest soils also provide other vital services including wildlife habitat and a regional economy driven by sustainable harvest of forest products and recreational opportunities. Many of these services are dependent on the balance between the rate at which rocks break down to recharge soil nutrient supply versus the rates at which materials are removed via tree harvest or are transported downstream. Uncertainty in mineral weathering rates, and whether such rates keep pace with losses, is a long-standing question in the sustainability of intensive forest harvest, and in understanding how forests respond to disturbances. This question has redoubled interest due to increasing demands on forests to provide renewable biomass energy sources in addition to more traditional forest products. Many of these same nutrient elements have been depleted by decades of air pollution. Accurate calculation of mineral weathering rates is the centerpiece of critical loads models, increasingly adopted by countries across the northern hemisphere as a tool to guide development of air pollution policy and for the management sustainable ecosystems. This study, taking place at the Hubbard Brook Experimental Forest in New Hampshire, will introduce a new paradigm of mineral weathering at the watershed-scale, describing spatial variation that can be used to reformulate mineral weathering algorithms in critical loads models and address nutrient depletion concerns for forest management. Working at Hubbard Brook with one of the longest records of stream and rainwater chemistry in North America provides a framework by which this research can demonstrate how different portions of watersheds interact to produce material flows transported by forests to downstream rivers and lakes. This will help foresters and watershed managers evaluate how management decisions may be applied to ensure continued productivity of upland forests of the northeastern U.S.Through measurement of hydrologic fluxes, solute fluxes and solid phase characterization at several sites in the northeastern U.S. and at the Hubbard Brook Experimental Forest, mineral weathering and regolith development processes will be examined along transects from exposed bedrock to deep soil, a common landscape gradient in glaciated regions. Data collected at three instrumented transects at Hubbard Brook will be used to test variation in mineral weathering gradients at the hillslope and watershed scale. Single transects at four sites dispersed across the northeastern U.S. will test applicability at the regional scale, with a broader range of climate, bedrock lithology and soil type. Mineral weathering processes, including both primary mineral dissolution and secondary material accumulation in zones hypothesized to represent functionally distinct portions of catchments, will be examined through solid phase studies of regolith (soil, subsoil, and rock fragments) and bedrock using overlapping analytical approaches, including optical petrography, scanning electrode microscopy, electron microprobe mapping, bulk chemical analyses, and secondary material extraction. The regolith studies, indicating long-term weathering progression, will be complemented by measurements of current aqueous flux in weathering derived elements using a combination of passive flow metering and more traditional hydrogeologic monitoring. Area normalized aqueous fluxes at four distinct zones within the catchment will be compared to catchment scale chemical denudation to determine the importance of the study zones to overall catchment mass balance. This will facilitate reinterpretation of a 50+ year record at Hubbard Brook, which will provide essential information for the assessment of forest sustainability by discerning the distinct rates and progression of processes at differing zones within upland catchments.

地球上薄薄的土壤使生命成为可能。水和岩石的相互作用，或矿物风化，负责维持生命并调节水质和流量的土壤的发育。因此，矿物风化是一项重要的自然服务，它提供植物生长所需的养分，并控制养分在环境中的循环及其向下游河流、湖泊、河口和海洋的运输。在这项研究中，美国东北部的山区提供了一个天然实验室来研究矿物风化的过程和速率，这些地区的土壤相对年轻（不到 10,000 年），基岩通常很浅，提供了整个地区矿物消耗和积累的空间梯度。景观。该地区土壤年轻，支撑着该国一些森林最茂密的州的森林，也是东北部主要河流的源头，为下游的主要大都市地区提供丰富、清洁的水源。 这些森林土壤还提供其他重要服务，包括野生动物栖息地以及由森林产品可持续采伐和娱乐机会驱动的区域经济。其中许多服务取决于岩石分解以补充土壤养分供应的速率与通过树木采伐或向下游运输材料的速率之间的平衡。矿物风化速率的不确定性，以及这种速率是否与损失保持同步，是森林集约采伐可持续性以及了解森林如何应对干扰的一个长期存在的问题。由于除了提供更传统的林产品外，对森林提供可再生生物质能源的需求不断增加，这个问题引起了人们的关注。 许多这些相同的营养元素已因数十年的空气污染而耗尽。矿物风化率的准确计算是临界负荷模型的核心，北半球各国越来越多地采用该模型作为指导空气污染政策制定和管理可持续生态系统的工具。 这项研究在新罕布什尔州的哈伯德布鲁克实验森林进行，将引入流域尺度的矿物风化的新范式，描述空间变化，可用于重新制定临界负荷模型中的矿物风化算法并解决养分消耗问题用于森林管理。哈伯德布鲁克拥有北美最长的河流和雨水化学记录之一，该研究提供了一个框架，通过该框架，这项研究可以展示流域的不同部分如何相互作用，产生由森林输送到下游河流和湖泊的物质流。这将帮助林务人员和流域管理者评估如何应用管理决策，以确保美国东北部高地森林的持续生产力。通过测量美国东北部和哈伯德布鲁克实验场的几个地点的水文通量、溶质通量和固相表征森林、矿物风化和风化层发育过程将沿着从暴露的基岩到深层土壤的横断面进行检查，这是冰川地区常见的景观梯度。在哈伯德布鲁克的三个仪器横断面收集的数据将用于测试山坡和流域范围内矿物风化梯度的变化。分布在美国东北部四个地点的单一样线将测试区域范围内的适用性，包括更广泛的气候、基岩岩性和土壤类型。矿物风化过程，包括假设代表流域功能不同部分的区域中的初级矿物溶解和次生物质积累，将通过使用重叠分析方法对风化层（土壤、底土和岩石碎片）和基岩进行固相研究进行检查，包括光学岩相学、扫描电极显微镜、电子探针测绘、大量化学分析和二次材料提取。表明长期风化进程的风化层研究将通过结合被动流量计量和更传统的水文地质监测对风化衍生元素中当前水通量的测量来补充。将流域内四个不同区域的面积归一化水通量与流域规模的化学剥蚀进行比较，以确定研究区域对整体流域质量平衡的重要性。 这将有助于重新解释哈伯德布鲁克 50 多年的记录，通过辨别高地流域内不同区域的不同速率和进程进展，为评估森林可持续性提供重要信息。

项目成果

Development of a lateral topographic weathering gradient in temperate forested podzols

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
• 发表时间: 2023-11
• 期刊: Geoderma
• 影响因子: 6.1
• 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.
• 通讯作者: Schreiber, Madeline E.

Hubbard Brook Experimental Forest: Watershed 3 Lateral Weathering Pedon Descriptions

哈伯德布鲁克实验林：分水岭 3 横向风化踏板描述

• DOI: 10.6073/pasta/ed5326149d2fea068d6c8d4d550718ec
• 发表时间: 2023-01
• 期刊: Environmental Data Initiative
• 作者: Bower, Jennifer A;Pennino, Amanda M;Bailey, Scott W;McGuire, Kevin J;Duston, Stephanie A
• 通讯作者: Duston, Stephanie A

Subsurface permeability contrasts control shallow groundwater flow dynamics in the critical zone of a glaciated, headwater catchment

地下渗透率对比控制冰川源头流域关键区域的浅层地下水流动态

• DOI: 10.1002/hyp.14672
• 发表时间: 2022-09
• 期刊: Hydrological Processes
• 影响因子: 3.2
• 作者: Benton, Joshua R.;McGuire, Kevin J.;Schreiber, Madeline E.
• 通讯作者: Schreiber, Madeline E.

Hubbard Brook Experimental Forest: Watershed 3 Subsurface Water Chemistry

哈伯德布鲁克实验森林：分水岭 3 地下水化学

• DOI: 10.6073/pasta/fe2c54e0c7d8c43f20c2b200555ca1f5
• 发表时间: 2022-01
• 期刊: Environmental Data Initiative
• 作者: Bailey, Scott W.;Gannon, John P.;McGuire, Kevin J.;Pardo, Linda H.
• 通讯作者: Pardo, Linda H.

Hubbard Brook Experimental Forest: Watershed 3 Lateral Weathering Soil Chemistry

哈伯德布鲁克实验森林：分水岭 3 横向风化土壤化学

• DOI: 10.6073/pasta/7348ab7d97a765b612687ba547a7aa47
• 发表时间: 2023-01
• 期刊: Environmental Data Initiative
• 作者: Bower, Jennifer A;Pennino, Amanda M;McGuire, Kevin J
• 通讯作者: McGuire, Kevin J