Effects of tree dieback on lake water acidity in the unmanaged catchment of Plešné Lake, Czech Republic. (11th February 2019)

• Record Type: Journal Article
• Authors: Kopáček, Jiří; Kaňa, Jiří; Porcal, Petr; Vrba, Jaroslav; Norton, Stephen A.
• Is Part Of: Limnology and oceanography. Volume 64:Number 4(2019)
• Page Start: 1614
• Page End: 1626
• Publication Date: 2019-02-11
• Subjects: Limnology -- Periodicals; Oceanography -- Periodicals; Océanographie; Limnologie; Limnology; Oceanography; Computer network resources; Périodique électronique (Descripteur de forme); Ressource Internet (Descripteur de forme); Periodicals; 551.4805
• DOI: 10.1002/lno.11139
• Languages: English
• ISSNs: 0024-3590

Abstract

Abstract: Terrestrial exports of protons (H + ), nitrate (NO3 − ), dissolved organic carbon including organic acid anions (A − ), phosphorus (P), base cations, and ionic aluminum (Ali ) underwent pronounced changes after bark beetle‐induced tree dieback (2004–2008) in a nitrogen‐saturated, chronically acidified but recovering catchment, Plešné Lake, Czech Republic. After a short decline in lake water pH immediately after tree dieback, the ecosystem recovery from acidification accelerated and the carbonate buffering system was restored by 2011, after ∼ 6 decades of depletion by acid rain. Major reasons for this rapid transition were changes in intensity of in‐lake biogeochemical (H + producing/removing) processes caused by changing concentrations and proportions of solutes exported from soil to surface water. In‐lake denitrification, elevated NO3 − assimilation (due to elevated P input), and photochemical/microbial oxidation of A − were the most important H + removing processes, while Ali hydrolysis was the most important H + source. Phytoplankton biomass increased with elevated P inputs and increasing P availability, which resulted from reduced in‐lake formation of Al hydroxide (and thus less adsorption of P) and more intensive P recycling by zooplankton. The rapidly changing lake water chemistry and elevated P availability after tree dieback in the catchment thus have enabled further biological recovery of Plešné Lake.