title: Long-term effects on nitrogen and benthic fauna of extreme weather events: Examples from two Swedish headwater streams.
abstract: Climate change is expected to cause an increased frequency of extreme events such as heavy floods and major storms. Such stochastic events have an immediate impact on surface water quality, but the long-term effects are largely unknown. In this study, we assess long-term monitoring data from two Swedish headwater catchments affected by extreme weather events. At one site, where nitrogen effects in soil water, groundwater, and stream water were studied after storm-felling and subsequent forest dieback from bark beetle attack, long-term (> 5 years) but relatively modest (generally <1 mg L⁻¹) increases in ammonium (NH(4)-N) and nitrate (NO(3)-N) concentrations were observed in the various aqueous media. At the other site, where effects on benthic fauna were studied in a stream impacted by extreme geophysical disturbances caused by rainstorm-induced flashflood, only short-term (1 year) effects were revealed both regarding diversity and composition of species.
authors.affiliation: Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, SLU, P.O. Box 7050, 750 07, Uppsala, Sweden, stefan.lofgren@slu.se.
authors.forename: Stefan
authors.initials: S
authors.lastname: Löfgren
authors.forename: Ulf
authors.initials: U
authors.lastname: Grandin
authors.forename: Sonja
authors.initials: S
authors.lastname: Stendera
mesh_terms: D000818:Animals; D057231:Climate Change; D004784:Environmental Monitoring; D055868:Floods; D019015:Geologic Sediments / Q000032:analysis; D060587:Groundwater / Q000032:analysis*; D007448:Invertebrates / Q000502:physiology*; D009584:Nitrogen / Q000032:analysis*; D011157:Population Dynamics; D045483:Rivers / Q000737:chemistry*; D012621:Seasons; D014887:Weather
chemical_list: D009584:Nitrogen