Enhanced biogenic carbon emissions in inland waterways: Insights from the Beijing-Hangzhou Grand Canal, China

Journal of Hydrology, Journal Year: 2025, Volume and Issue: unknown, P. 133148 - 133148

Published: March 1, 2025

Language: Английский

---

Human Activities Reshape Greenhouse Gas Emissions From Inland Waters

Global Change Biology, Journal Year: 2025, Volume and Issue: 31(3)

Published: March 1, 2025

ABSTRACT Inland waters are significant sources of greenhouse gases (GHGs) in an increasingly human‐dominated world, yet the mechanisms by which human activities reshape GHG emissions from these systems remain poorly understood. Here, we synthesized research three landscapes—agricultural, urban, and impounded river systems—to demonstrate that inland within exhibit significantly higher compared to their natural or seminatural counterparts. This is particularly evident for CH 4 N 2 O emissions, show median enhancement ratios 2.0–10 2.4–13 across systems, respectively. In contrast, CO overall lower (median < 2.0–3.1), largely due simultaneously increased photosynthetic uptake aquatic eutrophication. These observations underscore a clear footprint on underlying biogeochemical processes. The observed changes driven inputs sediments, carbon, nutrients human‐disturbed landscapes, coupled with expansion anoxia resulting metabolism, fine sediment deposition, Beyond altering emission rates, also modify abundance distribution waters, potentially exerting substantial, unquantified, effects landscape‐scale emissions. We highlight importance understanding processes accurately quantifying mitigating Future mitigation efforts should account variability discussed this review effectively address human‐induced waters.

Language: Английский

---

Differences in large instream wood between channelized and unchannelized agricultural headwater streams in the Midwestern United States

Deleted Journal, Journal Year: 2025, Volume and Issue: 2(1)

Published: April 28, 2025

Abstract The widespread use of channelization for agricultural drainage has resulted in the presence numerous channelized headwater streams Midwestern United States, Canada, and Europe. Channelization results removal instream wood that is a critical habitat feature. Quantitative information on characteristics within how they compare to unchannelized limited. We assessed diversity, frequency occurrence, amount large Ohio watershed by conducting small-scale field study retrospective analysis large-scale database. Our documented amounts central was similar values other streams. also quantified diversity greater than observed percentage sites with logs, root wads, mats were recovering or recently sites. others from States quantify stream reduces richness at least 1/2 These suggest may benefit management strategies increase these degraded

Language: Английский

---

Using 222Rn to quantify wetlands interflow volume and quality discharging to headwater streams

Applied Geochemistry, Journal Year: 2024, Volume and Issue: 169, P. 106037 - 106037

Published: May 21, 2024

Headwater streams are highly dependent on groundwater discharge to maintain low flows during dry periods and dilute pollutants. Groundwater can have different flow paths, either from flowing directly the river through hyporheic zone or that emerges at contact with a riparian wetland mainly surface. Differentiating these could be useful assess contribution of wetlands in protecting stream water quality. The objective this research was expand use 222Rn as tracer for small headwater catchments distinguish received aquifer wetlands. activities, phosphate (PO43-) nitrate (NO3-) concentrations, along were used mass balance model establish proportions located southwest Paris Basin (France). This watershed is typical region because it receives wastewater treatment plant (WWTP) effluent its source banks occupied by many To obtain best accuracy assessment, field work done conditions, where only 0.079 m3/s outlet. gives good estimation each path 83 % baseflow originating large contrast activity between inflow (mean 21200 Bq/m3) interflows 2310 renders sensitive separation two types paths. At head stream, characterized high concentrations PO43- NO3- due WWTP into (13 21 mg/L respectively). All free contribute improvement cycle more difficult constrain spatial heterogeneity concentrations. Nevertheless, results modeling approach showed main part evolution explained dilution interflows. method developed considered sufficiently accurate quantify inflows paths estimate impact

Language: Английский

---

How to Achieve a 50% Reduction in Nutrient Losses From Agricultural Catchments Under Different Climate Trajectories?

Earth s Future, Journal Year: 2024, Volume and Issue: 12(7)

Published: July 1, 2024

Abstract Under persistent eutrophication of European water bodies and a changing climate, there is an increasing need to evaluate best‐management practices for reducing nutrient losses from agricultural catchments. In this study, we set up daily discharge quality model in Hydrological Predictions the Environment two catchments representative common cropping systems Europe's humid continental regions forecast impacts future climate trajectories on loads. The predicted slight increase inorganic nitrogen (IN) total phosphorus (TP) loads under RCP2.6, likely due precipitation‐driven mobilization. RCP4.5 RCP8.5, IN were forecasted decrease 16% 26% 21%–50% respectively, most temperature‐driven increases crop uptake evapotranspiration. No distinct trends TP observed. A 50% loads, as targeted by Green Deal, was backcasted using combination management scenarios, including (a) 20% reduction mineral fertilizer application, (b) introducing cover crops (CC), (c) stream mitigation (SM) floodplains. Target load reductions could only be achieved SM, which results secondary mobilization sources within streams during high events. with reduction, CC, wherein required measures depended strongly climatic trajectory. Overall, study successfully demonstrated modeling approach evaluating diverging change trajectories, tailored catchment characteristics specific targets.

Language: Английский

---

Climate change accelerates water and biogeochemical cycles in temperate agricultural catchments

The Science of The Total Environment, Journal Year: 2024, Volume and Issue: 951, P. 175365 - 175365

Published: Aug. 6, 2024

Climate change is expected to significantly deteriorate water quality in heavily managed agricultural landscapes, however, the exact mechanisms of these impacts are unknown. In this study we adopted a modelling approach predict multiple effects climate on hydrological and biogeochemical responses for dominant solutes particulates two agriculture-dominated temperate headwater catchments. We used climatic projections from three models simulate future flows, mobilisation delivery particulates. This allowed an examination potential drivers by identifying changes flow pathway distribution key environmental variables. found that conditions will lead general increase stream discharge as well higher concentrations loads However, unlike previous studies, observed magnitude during warmer part year. These reduce relative importance winter flows solute particulate transport, leading both more evenly distributed between seasons. linked superficial pathways tile surface runoff driven rapid transition extremely wet dry conditions. Overall, widespread deterioration. Mitigation deterioration would require adequate management efforts address direct indirect negative biota scarcity.

Language: Английский

---

Nature-based bank protection measures improve benthic macroinvertebrates in a stream draining an agriculturally dominated watershed

Ecological Engineering, Journal Year: 2024, Volume and Issue: 208, P. 107377 - 107377

Published: Aug. 24, 2024

Language: Английский

---