Stream chemical response is mediated by hydrologic connectivity and fire severity in a Pacific Northwest forest DOI
Sidney Bush, Sherri L. Johnson, Kevin D. Bladon

et al.

Hydrological Processes, Journal Year: 2024, Volume and Issue: 38(7)

Published: July 1, 2024

Abstract Large‐scale wildfires are becoming increasingly common in the wet forests of Pacific Northwest (USA), with predicted increases fire prevalence under future climate scenarios. Wildfires can alter streamflow response to precipitation and mobilize water quality constituents, which pose a risk aquatic ecosystems downstream drinking treatment. Research often focuses on impacts high‐severity wildfires, stream biogeochemical responses low‐ mixed‐severity fires understudied, particularly during seasonal shifts hydrologic connectivity between hillslopes streams. We studied 2020 Holiday Farm Fire at HJ Andrews Experimental Forest where rare pre‐fire discharge chemistry data allowed us evaluate influence quantity quality. Our research design focused two well‐studied watersheds low low‐moderate burn severity we examined long‐term (pre‐ post‐fire), instantaneous grab samples collected four rain events occurring immediately following wildfire prolonged dry summer. analysed impact these events, represent transition from low‐to‐high subsurface stream, behaviour. Long‐term revealed total annual flows mean remained fairly consistent post‐fire, while small baseflow were observed low‐moderately burned watershed. Stream concentrations nitrate, phosphate sulfate significantly increased fire, variance concentration increasing severity. end member mixing models suggested that watershed had greater inputs soil groundwater times compared fire. Finally, differences concentration‐discharge relationships biogenic solutes most expressed catchment conditions. study provides insights into post‐wildfire quality, goal informing low, moderate mixed wildfire.

Language: Английский

Hidden Features: How Subsurface and Landscape Heterogeneity Govern Hydrologic Connectivity and Stream Chemistry in a Montane Watershed DOI
Keira Johnson, Kenneth H. Williams, John N. Christensen

et al.

Hydrological Processes, Journal Year: 2025, Volume and Issue: 39(3)

Published: March 1, 2025

ABSTRACT Hydrologic connectivity is defined as the connection among stores of water within a watershed and controls flux solutes from subsurface to stream. difficult quantify because it goverened by heterogeniety in storage permeability responds seasonal changes precipitation inputs moisture conditions. How interannual climate variability impacts hydrologic connectivity, thus stream flow generation chemistry, remains unclear. Using rare, four‐year synoptic chemistry dataset, we evaluated shifts source Coal Creek, montane, headwater tributary Upper Colorado River. We leveraged compositional principal component analysis end‐member mixing evaluate how variation conditions chemistry. Overall, three main findings emerged this work. First, geochemically distinct end members were identified that constrained chemistry: reach inflows, quick slow groundwater contributions. Reach inflows impacted historic base precious metal mine inputs. Bedrock fractures facilitated much transport higher‐storage features (e.g., alluvial fans) groundwater. Second, contributions different changed over summer. In early summer, was composed all members, while late predominantly Finally, observed minimal differences proportional composition across four years, indicating spatial heterogeneity landscape geologic had greater influence than fluctuation on These indicate mechanisms controlling solute path activation) may be resilient (i.e., able rebound after perturbations) predicted increases variability. By establishing framework for assessing variable conditions, our study offers method biogeochemical resilience variations hydrometeorological

Language: Английский

Citations

0
Mechanisms of climate-induced lake dynamics in the Source Region of Three Rivers, Tibetan Plateau DOI
Xiafei Zheng,

S. Liang,

Dezhao Yan

et al.

Journal of Hydrology Regional Studies, Journal Year: 2025, Volume and Issue: 59, P. 102323 - 102323

Published: March 22, 2025

Language: Английский

Citations

0
Controls From Above and Below: Snow, Soil, and Steepness Drive Diverging Trends of Subsurface Water and Streamflow Dynamics DOI Creative Commons
Devon Kerins, Abigail S. Knapp,

Fiona S. Liu

et al.

Hydrological Processes, Journal Year: 2025, Volume and Issue: 39(4)

Published: April 1, 2025

ABSTRACT The importance of subsurface water dynamics, such as storage and flow partitioning, is well recognised. Yet, our understanding their drivers links to streamflow generation has remained elusive, especially in small headwater streams that are often data‐limited but crucial for downstream quantity quality. Large‐scale analyses have focused on characteristics across rivers with varying drainage areas, overlooking the dynamics shape behaviour. Here we ask question: What climate landscape regulate dynamic storage, path streams? To answer this question, used data a widely‐used hydrological model (HBV) 15 catchments contiguous United States. Results show aridity precipitation phase (snow or rain) land attributes topography soil texture key dynamics. In particular, steeper slopes generally promoted more streamflow, regardless aridity. Streams flat, rainy sites (< 30% snow) finer soils exhibited flashier regimes than those snowy (> coarse deeper paths. sites, less weathered, thinner shallower paths discharge was sensitive changes snow dampened flashiness overall. here indicate steepness modify shallow deep ultimately regulating response forcing. As change increases uncertainty availability, interacting features will be essential predict shifts improve resources management.

Language: Английский

Citations

0
Natural and anthropogenic factors controlling hydrogeochemical processes in a fractured granite bedrock aquifer, Korea DOI Creative Commons
Jiyun Kim, Jaeyeon Kim,

Dugin Kaown

et al.

Environmental Monitoring and Assessment, Journal Year: 2025, Volume and Issue: 197(5)

Published: April 30, 2025

Language: Английский

Citations

0
Stream chemical response is mediated by hydrologic connectivity and fire severity in a Pacific Northwest forest DOI
Sidney Bush, Sherri L. Johnson, Kevin D. Bladon

et al.

Hydrological Processes, Journal Year: 2024, Volume and Issue: 38(7)

Published: July 1, 2024

Abstract Large‐scale wildfires are becoming increasingly common in the wet forests of Pacific Northwest (USA), with predicted increases fire prevalence under future climate scenarios. Wildfires can alter streamflow response to precipitation and mobilize water quality constituents, which pose a risk aquatic ecosystems downstream drinking treatment. Research often focuses on impacts high‐severity wildfires, stream biogeochemical responses low‐ mixed‐severity fires understudied, particularly during seasonal shifts hydrologic connectivity between hillslopes streams. We studied 2020 Holiday Farm Fire at HJ Andrews Experimental Forest where rare pre‐fire discharge chemistry data allowed us evaluate influence quantity quality. Our research design focused two well‐studied watersheds low low‐moderate burn severity we examined long‐term (pre‐ post‐fire), instantaneous grab samples collected four rain events occurring immediately following wildfire prolonged dry summer. analysed impact these events, represent transition from low‐to‐high subsurface stream, behaviour. Long‐term revealed total annual flows mean remained fairly consistent post‐fire, while small baseflow were observed low‐moderately burned watershed. Stream concentrations nitrate, phosphate sulfate significantly increased fire, variance concentration increasing severity. end member mixing models suggested that watershed had greater inputs soil groundwater times compared fire. Finally, differences concentration‐discharge relationships biogenic solutes most expressed catchment conditions. study provides insights into post‐wildfire quality, goal informing low, moderate mixed wildfire.

Language: Английский

Citations

1