Article
Environmental Sciences
Mark A. Torres, J. Jotautas Baronas
Summary: The study demonstrates that changes in the shape of the transit time distribution can affect C-Q relationships, resulting in a wide range of cation-Q and Si-Q relationships. The sensitivity of C-Q relationships to hydrologic variability and reaction rates is highlighted.
GLOBAL BIOGEOCHEMICAL CYCLES
(2021)
Review
Environmental Sciences
M. D. Covington, J. B. Martin, L. E. Toran, J. L. Macalady, N. Sekhon, P. L. Sullivan, A. A. Garcia, J. B. Heffernan, W. D. Graham
Summary: Earth's Critical Zone (CZ), influenced by underlying bedrock, is extensively studied for silicate-dominated landscapes but less so for carbonate landscapes. However, carbonate rocks cover around 15% of Earth's surface and provide essential resources. This study reviews the state of knowledge of the carbonate CZ, explores contrasts in different carbonate settings, and calls for integrative studies to develop a conceptual framework for the role of carbonates in the CZ.
Article
Geosciences, Multidisciplinary
David N. Dralle, W. Jesse Hahm, Daniella M. Rempe
Summary: Accurate observation of hillslope groundwater storage and instantaneous recharge remains difficult due to limited monitoring and complex mountainous landscapes. A novel storage-discharge method is introduced to estimate hillslope recharge and recharge ratio, which relies on streamflow data and is validated with independent measurements. The method offers valuable insights into controls on groundwater recharge, enhancing our understanding of a critical flux in the hydrologic cycle.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geochemistry & Geophysics
Johanna Noireaux, Pamela L. Sullivan, Jerome Gaillardet, Pascale Louvat, Grit Steinhoefel, Susan L. Brantley
Summary: The study examines boron isotopes in different watershed components to understand water-rock interactions in a shale dominated watershed. Results show similarities in boron isotopes between bedrock and soil, while surface waters are enriched in boron compared to other compartments. Modeling suggests that surface water and groundwater isotopic fractionation is mainly due to water-rock interactions.
Article
Geochemistry & Geophysics
Jon K. Golla, Marie L. Kuessner, Michael J. Henehan, Julien Bouchez, Daniella M. Rempe, Jennifer L. Druhan
Summary: This study investigates the fractionation process of lithium isotopes during silicate weathering by directly measuring the isotopic ratios in water samples. The results show changing patterns of Li isotopic signatures at different depths in the weathering profile, reflecting variations in weathering processes. The study presents a multicomponent reactive transport framework to model the progression of Li isotopes and provides insights for using stable isotopes in studying catchment-scale chemical weathering fluxes.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)
Article
Geosciences, Multidisciplinary
Sylvain Pasquet, Jean Marcais, Jorden L. Hayes, Peter B. Sak, Lin Ma, Jerome Gaillardet
Summary: Weathering and erosion processes are essential for CZ evolution and availability of natural resources. This study proposes a novel workflow using near-surface geophysics to characterize the architecture of the deep CZ at a catchment scale on a volcanic tropical island, revealing complex weathering patterns.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Engineering, Civil
Jun Zhang, Hongsong Chen, Zhiyong Fu, Fa Wang, Kelin Wang
Summary: The hydrological connectivity along the hillslope critical zone in southwest China was investigated. It was found that soil depth gradually increased from up-slope to down-slope, and rainwater infiltrated the soil and eventually converged in the low-lying area through the soil-epikarst interface. Contrary to expectations, the soil-epikarst interface in shallow soil-covered hillslopes had higher moisture content, indicating slower renewal cycle of groundwater.
JOURNAL OF HYDROLOGY
(2023)
Article
Geochemistry & Geophysics
Andrew D. Parsekian, Dario Grana, Felipe dos Anjos Neves, Mark S. Pleasants, Mark Seyfried, Bryan G. Moravec, Jon Chorover, Anthony M. Moraes, Natalie Y. Smeltz, John H. Westenhoff, Thijs Kelleners
Summary: This study demonstrates that hydrogeo-physical imaging provides valuable insights into belowground architecture, which is crucial for driving hydrologic models and interpreting weathering processes. By utilizing classification models and facies classification methods, differences in belowground architectures between different locations can be revealed, leading to improved interdisciplinary models of CZ processes at various scales.
Article
Geosciences, Multidisciplinary
Berit Hudson M. Rasmussen, Mong-Han Huang, W. Jesse Hahm, Daniella M. Rempe, David Dralle, Mariel D. Nelson
Summary: This study examines the variation in soil thickness and bedrock weathering across ridge and valley topography in the Northern California Coast Ranges. Seismic surveys and borehole observations reveal a high velocity gradient zone located beneath ridgetops, which coincides with transitions in material strength and chemical depletion. Despite differing slope aspects, the thickness of saprolite remains consistent. The aspect-independent weathering structure suggests a legacy of past climate and vegetation conditions at the study site.
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2023)
Article
Geosciences, Multidisciplinary
Patrick J. Frings, Marcus Oelze, Franziska Schubring, Daniel A. Frick, Friedhelm von Blanckenburg
Summary: Metal and metalloid stable isotope ratios are important proxies for weathering, element cycling, and export in the Critical Zone. By studying sites with varying erosion rates and regolith residence times, it was found that three key parameters influence these isotope ratios, particularly in the case of silicon. The research also highlights how the composition of clay minerals plays a significant role in expressing fractionation factors related to silicon isotope ratios.
AMERICAN JOURNAL OF SCIENCE
(2021)
Article
Environmental Sciences
Hongyi Li, Ali A. Ameli
Summary: Large-scale cross-site scientific synthesis can help develop transferable hypotheses on the impacts of critical zone attributes interactions on catchments' water vulnerabilities.
WATER RESOURCES RESEARCH
(2023)
Article
Geosciences, Multidisciplinary
Matthew J. Winnick, Jennifer L. Druhan, Kate Maher
Summary: Lithium isotopes are a powerful tool for studying the response of global weathering to climate change. This study examines the relationship between lithium isotopes, concentration, and weathering regime, and proposes that rapid weathering of soluble lithium-rich minerals and geothermal lithium sources can explain observed patterns.
AMERICAN JOURNAL OF SCIENCE
(2022)
Article
Engineering, Environmental
Susanga Costa, Mahitha Cherukuvada, Tanvirul Islam, Jayantha Kodikara
Summary: This study investigates the variation of suction, moisture content and temperature in soil under changing climatic conditions, using a numerical model. The predictions indicate that there will be an increase in suction and ground temperature, while soil moisture content decreases in the future. It is recommended that soil characteristics and depth to water table should be considered when estimating ground suction.
BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT
(2023)
Review
Environmental Sciences
Ya-Sin Yang, Hsin-Fu Yeh, Chia-Chi Huang, Hsin-Yu Chen
Summary: Due to active orogenic movement and the monsoon climate, rainfall-induced landslide disasters often occur in Taiwan. Research on hillslope hydrology and stability is complicated by spatial heterogeneity, hydrological processes operating at various scales, spatiotemporal evolution, and geomorphological properties. Recent advances in critical zone science provide a framework for integrating physical, chemical, and biological processes and addressing the challenges related to hillslope hydrology and stability. This study reviews the progress, relevance, and common challenges in hillslope hydrology, stability, and critical zone science, and presents a process-based integrated monitoring strategy, an interdisciplinary perspective, and a coupling analysis framework and model to promote the research on hillslope stability and hydrology in Taiwan.
Article
Physics, Applied
Huan Zhao, Lijun Wang, Jie Liu
Summary: Based on a two dimensional self-consistent model, the effect of different CF4 concentrations on the discharge dynamics characteristics, species distribution and ionization rates of He atmospheric pressure plasma jet (APPJ) has been investigated. The study found that the ionization rate of He APPJ increases with the increase of CF4 concentration up to a certain level and then decreases. The increase of CF4 concentration leads to a decrease in CF4+ density and CF3+ density, but an increase in CF3- and F- densities. The ionization reaction of CF4 primarily occurs at the streamer head, while the Penning ionization of CF4 dominates the formation of ionization wave tail. The increasing CF4 concentration results in a higher electron impact ionization rate near the axis, leading to a more uniform radial ionization rate distribution in He + 2% CF4 APPJ.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2023)
Article
Geosciences, Multidisciplinary
David O. S. Oakley, Brandon Forsythe, Xin Gu, Andrew A. Nyblade, Susan L. Brantley
Summary: By analyzing high-frequency ambient seismic noise data, temporal changes in seismic velocities in the critical zone from 1 to tens of meters deep were detected, driven by variations at the land surface. Most velocity changes can be explained by variations in temperature, while some double minima in seismic velocity time-series were attributed to the effects of water infiltration.
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2021)
Article
Environmental Sciences
Hang Wen, Susan L. Brantley, Kenneth J. Davis, Jonathan M. Duncan, Li Li
Summary: The study compared the performance of complex and simple models in simulating hydrological dynamics at Shale Hills watershed, finding that the simple model can reproduce some hydrological dynamics but has limitations in ignoring spatial details.
WATER RESOURCES RESEARCH
(2021)
Article
Environmental Sciences
Li Li, Bryn Stewart, Wei Zhi, Kayalvizhi Sadayappan, Shreya Ramesh, Devon Kerins, Gary Sterle, Adrian Harpold, Julia Perdrial
Summary: This study examines the patterns and drivers of river chemistry by analyzing chemistry data from 506 minimally impacted rivers in the United States. The results show a universal pattern of decreasing solute concentrations with increased discharge, indicating that climate plays a dominant role in regulating river chemistry compared to local characteristics. A watershed reactor model is used to understand the relationship between solute concentrations and discharge, revealing the competing processes of solute production and export. These findings have implications for water quality and aquatic ecosystems in a warming climate.
Article
Environmental Sciences
Bryn Stewart, Wei Zhi, Kayalvizhi Sadayappan, Gary Sterle, Adrian Harpold, Li Li
Summary: The study investigates DIC concentrations in over 100 minimally-impacted rivers in the contiguous United States. The results show that instantaneous concentrations are strongly influenced by changes in river discharge, while mean concentrations are regulated by climate. The study highlights the significance of subsurface flow paths in land-river connectivity and emphasizes the importance of characterizing subsurface CO2 distribution.
GLOBAL BIOGEOCHEMICAL CYCLES
(2022)
Article
Water Resources
Julia L. A. Knapp, Li Li, Andreas Musolff
Summary: This study analyzes long-term low-frequency data from four UK catchments using antecedent catchment wetness as a proxy for lateral hydrologic connectivity. The results demonstrate that solute mobilization mechanisms can vary depending on catchment wetness, as different catchment areas become hydrologically connected to or disconnected from streams. It also shows that flow and streamwater chemistry are mostly decoupled under dry conditions, with solute sources having a stronger impact on mobilization patterns during dry conditions compared to wet conditions.
HYDROLOGICAL PROCESSES
(2022)
Article
Engineering, Environmental
Devon Kerins, Li Li
Summary: Warming in mountains leads to higher concentrations of dissolved carbon in streams, especially in arid mountain areas. This indicates deteriorating water quality and changes in soil carbon dynamics, which have significant implications for global water resources and environmental sustainability.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Environmental Sciences
Andrew R. Shaughnessy, Michael J. Forgeng, Tao Wen, Xin Gu, Jordon D. Hemingway, Susan L. Brantley
Summary: With the growing scarcity of drinking water worldwide, it is important to improve predictions of water resources quantity and quality. A major problem for model improvement is the lack of detailed knowledge about the geological structure of aquifers. This research shows that mineral-water reactions leave imprints in the subsurface, affecting the flow and transport of chemical species. Understanding these patterns can help manage water resources in the future under accelerated land use and climate change.
WATER RESOURCES RESEARCH
(2023)
Article
Environmental Sciences
Kristen L. Underwood, Donna M. Rizzo, John P. Hanley, Gary Sterle, Adrian Harpold, Thomas Adler, Li Li, Hang Wen, Julia N. Perdrial
Summary: Research at long-term catchment monitoring sites has generated a great volume, variety, and velocity of data for analysis of stream water chemistry dynamics. Machine learning tools have advantages over traditional statistical methods in extracting patterns from big data, but they may struggle to identify multivariate factor interactions and equifinality, which are common in catchments.
WATER RESOURCES RESEARCH
(2023)
Article
Soil Science
Aaron N. Koop, Daniel R. Hirmas, Sharon A. Billings, Li Li, Alejandro Cueva, Xi Zhang, Hang Wen, Attila Nemes, Ligia F. T. Souza, Hoori Ajami, Alejandro N. Flores, Aoesta K. Rudick, Annalise Guthrie, Lola M. Klamm, Micah Unruh, Pamela L. Sullivan
Summary: Climate-induced soil structural changes are occurring rapidly at yearly to decadal timescales, making it important to understand the properties and mechanisms controlling soil structure and macroporosity. This study shows that the complexed fraction of soil organic carbon and clay strongly influence effective porosity in both surface and subsurface horizons. The relationship between effective porosity and complexed organic carbon and clay can help predict future changes in soil hydraulic properties.
Article
Soil Science
Ligia F. T. Souza, Daniel R. Hirmas, Pamela L. Sullivan, Daniel C. Reuman, Matthew F. Kirk, Li Li, Hoori Ajami, Hang Wen, Marcos V. M. Sarto, Terry D. Loecke, Aoesta K. Rudick, Charles W. Rice, Sharon A. Billings
Summary: The distribution of soil organic carbon (SOC) is influenced by various ecosystem features, such as differential carbon inputs in shallow and deep soils and carbon redistribution through water flow. This study investigates the impact of land use conversion on SOC loss and retention, focusing on Mollisols. The research uses both regional-scale and local-scale datasets to understand the mechanisms driving SOC depth distributions and reveals the importance of root abundances and water availability in shaping vertical water flow and carbon transport.
Article
Environmental Sciences
Keira Johnson, Adrian Harpold, Rosemary W. H. Carroll, Holly Barnard, Mark S. Raleigh, Catalina Segura, Li Li, Kenneth H. Williams, Wenming Dong, Pamela L. Sullivan
Summary: Summer streamflow predictions are crucial for water resource management, but shifts from snow to rain regimes and reductions in snowpack affect low-flow predictive models. Understanding the variability of groundwater contributions is important for predicting summer low flows. This study quantifies the groundwater contribution during the recession limb to predict summer low flows in three western US watersheds. The results show that recession limb groundwater is a strong predictor of low flows across all sites and significantly improves prediction compared to snow metrics at rain-dominated sites. The study suggests that the control of recession limb groundwater on summer low flows may be mediated by subsurface storage, with the proportion of dynamic storage being a key factor. Including recession limb groundwater improves low-flow prediction in diverse watersheds.
WATER RESOURCES RESEARCH
(2023)
Article
Environmental Sciences
Wei Zhi, Christoph Klingler, Jiangtao Liu, Li Li
Summary: This study reconstructed daily water temperature and dissolved oxygen in rivers across the United States and Central Europe using a deep learning model. The results showed that a majority of the rivers experienced persistent warming and deoxygenation, with urban rivers exhibiting the most rapid warming and agricultural rivers experiencing the slowest warming but fastest deoxygenation.
NATURE CLIMATE CHANGE
(2023)
Article
Environmental Sciences
Chaopeng Shen, Alison P. P. Appling, Pierre Gentine, Toshiyuki Bandai, Hoshin Gupta, Alexandre Tartakovsky, Marco Baity-Jesi, Fabrizio Fenicia, Daniel Kifer, Li Li, Xiaofeng Liu, Wei Ren, Yi Zheng, Ciaran J. J. Harman, Martyn Clark, Matthew Farthing, Dapeng Feng, Praveen Kumar, Doaa Aboelyazeed, Farshid Rahmani, Yalan Song, Hylke E. E. Beck, Tadd Bindas, Dipankar Dwivedi, Kuai Fang, Marvin Hoge, Chris Rackauckas, Binayak Mohanty, Tirthankar Roy, Chonggang Xu, Kathryn Lawson
Summary: Differentiable modelling integrates the learning ability of machine learning with the interpretability of process-based models. It improves representation of processes, parameter estimation, and predictive accuracy in the geosciences. By connecting prior physical knowledge to neural networks, differentiable modelling combines process-based modelling and machine learning, offering better interpretability, generalizability, and extrapolation capabilities. It requires less training data compared to purely data-driven machine learning and scales well with increasing data volumes. Under data-scarce scenarios, it outperforms machine-learning models in capturing short-term dynamics and decadal-scale trends due to the imposed physical constraints.
NATURE REVIEWS EARTH & ENVIRONMENT
(2023)
Article
Geosciences, Multidisciplinary
Wei Zhi, Yuning Shi, Hang Wen, Leila Saberi, Gene-Hua Crystal Ng, Kayalvizhi Sadayappan, Devon Kerins, Bryn Stewart, Li Li
Summary: Watersheds are fundamental units that connect land to aquatic systems. This paper presents a watershed-scale biogeochemical reactive transport model that can simulate both hydrological and biogeochemical processes. The model has been applied in multiple watersheds and can help understand the coupled processes under different conditions.
GEOSCIENTIFIC MODEL DEVELOPMENT
(2022)
