Disentangling the Impact of Catchment Heterogeneity on Nitrate Export Dynamics From Event to Long‐Term Time Scales

Water Resources Research, Journal Year: 2020, Volume and Issue: 57(1)

Published: Dec. 8, 2020

Abstract Defining effective measures to reduce nitrate pollution in heterogeneous mesoscale catchments remains challenging when based on concentration measurements at the outlet only. One reason for this is our limited understanding of subcatchment contributions export and their importance different time scales. While upstream subcatchments often disproportionally contribute runoff generation turn nutrient export, agricultural areas (which are typically found downstream lowlands) known be a major source pollution. To examine interplay subcatchments, we analyzed seasonal long‐term trends event dynamics concentrations, loads, concentration–discharge relationship three nested within Selke catchment (456 km 2 ), Germany. The (40.4% total area, 34.5% N input) had short transit times dynamic relationships with elevated concentrations during wet seasons events. Consequently, dominated high flow contributed overall annual loads (64.2%). was characterized by higher input, longer times, relatively constant between seasons, dominating low‐flow periods. Neglecting disproportional role temporally net can lead an overestimation lowlands. Nonetheless, constantly from legacies pose threat water quality This knowledge crucial site‐specific management.

Language: Английский

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Droughts can reduce the nitrogen retention capacity of catchments

Hydrology and earth system sciences, Journal Year: 2023, Volume and Issue: 27(1), P. 303 - 318

Published: Jan. 13, 2023

Abstract. In 2018–2019, Central Europe experienced an unprecedented 2-year drought with severe impacts on society and ecosystems. this study, we analyzed the impact of water quality by comparing long-term (1997–2017) nitrate export 2018–2019 in a heterogeneous mesoscale catchment. We combined data-driven analysis process-based modeling to analyze nitrogen retention underlying mechanisms soils during subsurface transport. found drought-induced shift concentration–discharge relationships, reflecting exceptionally low riverine concentrations dry periods high subsequent wet periods. Nitrate loads were up 73 % higher compared load–discharge relationship. Model simulations confirmed that increase was driven decreased denitrification plant uptake flushing accumulated rewetting. Fast transit times (<2 months) upstream sub-catchments enabled fast response drought. contrast, longer downstream (>20 years) inhibited but potentially contribute legacy. Overall, our study reveals droughts, which are predicted become more frequent across Europe, can reduce capacity catchments, thereby intensifying pollution threatening quality.

Language: Английский

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Vegetation browning: global drivers, impacts, and feedbacks

Trends in Plant Science, Journal Year: 2023, Volume and Issue: 28(9), P. 1014 - 1032

Published: April 21, 2023

Language: Английский

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Model-aided quantification of dissolved carbon and nitrogen release after windthrow disturbance in an Austrian karst system

Biogeosciences, Journal Year: 2016, Volume and Issue: 13(1), P. 159 - 174

Published: Jan. 15, 2016

Abstract. Karst systems are important for drinking water supply. Future climate projections indicate increasing temperature and a higher frequency of strong weather events. Both will influence the availability quality provided from karst regions. Forest disturbances such as windthrow can disrupt ecosystem cycles cause pronounced nutrient losses ecosystems. In this study, we consider time period before after wind disturbance (2007/08) to identify impacts on DIN (dissolved inorganic nitrogen) DOC organic carbon) with process-based flow solute transport simulation model. When calibrated validated disturbance, model disregards forest its consequences production leaching. It therefore be used baseline undisturbed system tool quantification additional production. Our results that by in significant increase lasting ∼ 3.7 years exceeding pre-disturbance average 2.7 kg ha−1 a−1 corresponding an 53 %. There were no changes concentrations. With simulated transit distributions show impact travels through hydrological within some months. However, small fraction outflow (< 5 %) exceeds mean times > 1 year.

Language: Английский

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Consequences of mountain pine beetle outbreak on forest ecosystem services in western Canada

Canadian Journal of Forest Research, Journal Year: 2016, Volume and Issue: 46(8), P. 987 - 999

Published: June 6, 2016

After affecting millions of hectares pine forests in western Canada, the mountain beetle (MPB; Dendroctonous ponderosae Hopkins) is spreading out its native range and into Canada’s boreal forest. Impacts outbreaks can be environmental, economic, social, an ecosystem services (ES) viewpoint provides a useful perspective for integrated approach to assessing these impacts may help identify how possible management strategies could minimize impacts. In this regards, comprehensive overview functions socioeconomic factors that have been impacted by current Canada was carried facilitate more general ES assessment. addition timber production, MPB negative effects on provisioning (water supply food production) aesthetic cultural services, while regulating (carbon forest fire) are still debate. Among supporting nutrient cycling aquatic habitat showed short- long-term effects, terrestrial mostly positive response. The overall impact severe if salvage logging practiced as post-MPB strategy. outcomes study areas greatest socioecological vulnerability knowledge gaps avenues research advance framework outbreak management.

Language: Английский

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