Manganese Biogeochemistry in a Central Czech Republic Catchment

Abstract

Mn biogeochemistry was studied from 1994 to 2003 in a small forested catchment in the central Czech Republic using the watershed mass balance approach together with measurements of internal stores and fluxes. Mn inputs in bulk deposition were relatively constant during a period of sharply decreasing acidic deposition, suggesting that the Mn source was terrestrial, and not from fossil fuel combustion. Mn inputs in bulk deposition and Mn supplied by weathering each averaged 13 mg m −2 year −1 (26 mg m −2 year −1 total input), whereas Mn export in streamwater and groundwater averaged 43 mg m −2 year −1 . Thus an additional Mn source is needed to account for 17 mg m −2 year −1 . Internal fluxes and pools of Mn were significantly greater than annual inputs and outputs. Throughfall Mn flux was 70 mg m −2 year −1 , litterfall Mn flux was 103 mg m −2 year −1 , and Mn net uptake by vegetation was 62 mg m −2 year −1 . Large pools of labile or potentially labile Mn were present in biomass and surficial soil horizons. Small leakages from these large pools likely supply the additional Mn needed to close the watershed mass balance. This leakage may reflect an adjustment of the ecosystem to recent changes in atmospheric acidity.

Hydroclimatic control of sediment and metal export from a rural catchment in northwestern Spain

“…By contrast, the Fe D and Mn D load was higher in 2007/08, which was the driest year and with lesser streamflow but higher baseflow (Palleiro et al, 2014). Since the catchment lacks significant sources of pollution, it is likely that these dissolved metals are present in groundwater, with longer residence time in rocks and soils than the surface water, and thus, with a higher power of weathering (Nagano et al, 2003;Navrátil et al, 2007).…”

The effects of dissolved organic carbon, acidity and seasonality on metal geochemistry within a forested catchment on the Precambrian Shield, central Ontario, Canada

“…Evaporative concentration of solutes increases metal concentrations in soil water (*50% of precipitation is lost as evapotranspiration at PC1; Devito et al 1989). Metals exhibiting the highest concentrations in the LFH soil water are those with strong DOC associations (As, Cu, Pb, Rb, Tl and V) or those especially available for plant uptake (Mn and Cd; Navratil et al 2007;Tyler 2004). In the forest floor soil water, all metals are associated with DOC, indicating that DOC production is a primary factor enhancing metal mobility in this horizon.…”

Metal Pools, Fluxes, and Budgets in an Acidified Forested Catchment on the Precambrian Shield, Central Ontario, Canada

“…The high enrichment factors for As, Cd, Pb, and Zn in bulk deposition suggests the elevated forest floor concentrations can be attributed to pollution inputs. Uptake of metals from lower soil horizons and deposition of metalenriched foliage increased concentrations of Cd, Mn, and Zn in the forest floor (Alriksson and Eriksson 2001;Heinrichs and Mayer 1980;Navratil et al 2007). The metals Co, Cr, and V have the highest concentrations in the mineral B horizon, indicating that they have been leached from the upper soil horizons and have minimal internal cycling.…”