Fluxes of ecologically important solutes in the Čertovo catchment–lake system from 1998–2017

0498088 - BC 2019 RIV CZ eng J - Článek v odborném periodiku
Kopáček, Jiří - Hejzlar, Josef - Kaňa, Jiří - Porcal, Petr - Turek, Jan
Fluxes of ecologically important solutes in the Čertovo catchment–lake system from 1998–2017.
Silva Gabreta. Roč. 24, č. 1 (2018), s. 85-114. ISSN 1211-7420
Grant CEP: GA ČR GA17-15229S
Grant ostatní: TCP ERDF(CZ) 26
Program: Programu přeshraniční spolupráce Česká republika – Svobodný stát Bavorsko Cíl EÚS 2014 – 2020
Institucionální podpora: RVO:60077344
Klíčová slova: recovery from acidification * nitrogen * sulphur * organic carbon * aluminium
Obor OECD: Environmental sciences (social aspects to be 5.7)

Fluxes of major ions and nutrients were measured in the catchment–lake system of atmospherically acidified Čertovo Lake between 1998 and 2017 hydrological years. Water balance was calculated from precipitation and throughfall amounts, and measured outflow from the lake. The average water outflow from the system was 1216 mm/yr, and the water residence time in the lake averaged 649 days. The Čertovo catchment remained an average net source of protons (440 eq/ha/yr) despite significant reductions in sulphur and nitrogen deposition since the late 1980s. Nitrogen saturation of the catchment soils caused low retention of the deposited inorganic N (23% on average) and the terrestrial ammonium removal and nitrate production via nitrification (500 and 250 eq/ha/yr, respectively) were the major terrestrial sources of protons. Net terrestrial sulphate production (the second most important proton source) decreased from 490 to 310 eq/ha/yr between 1998–2002 and 2013–2017, and this decrease was accompanied by decreasing production of ionic Al (Ali) forms from 470 to 260 eq/ha/yr. The increasing terrestrial production of organic acid anions (A) compensated for the decreasing sulphate leaching and maintained (and stabilized) low pH (4.1–4.5) in lake tributaries during the study period. Compared to precipitation, the catchment was a net source of all ions and nutrients (except for ammonium). The in-lake biogeochemical processes reduced the incoming protons by 40% (i.e., neutralized on average 2230 eq/ha/yr protons on a lake-area basis). The nitrate and sulphate reductions and photochemical and microbial oxidation of A were the most important proton neutralizing processes (1840, 380, and 1400 eq/ha/yr, respectively), while hydrolysis of Ali was the dominant proton generating process (790 eq/ha/yr). The lake was a net sink for all nutrients, removing on average 13–38% of total (terrestrial and atmospheric) inputs of dissolved organic carbon, phosphorus, nitrogen, and silicon.
Trvalý link: http://hdl.handle.net/11104/0290539