Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Photochemical mineralisation of dissolved organic matter in lake Skjervatjern
AbstractPhotochemical mineralisation of dissolved organic matter (DOM) of a moderately humic lake was studied in 0.1 or 0.2 μm filtered water incubated in glass and quartz bottles. The direct measurement of mineralisation as an increase of dissolved inorganic carbon (DIC) proved to be a very useful tool when the concentration of DIC is low. At the lake surface, photochemical mineralisation was considerably higher in quartz than glass bottles indicating that UV light is the most important mineraliser of DOM. Because the glass bottles penetrated light well down to 340–350 nm wavelength, the photochemically most intensive part of solar radiation was in the range of UV-B. Higher photochemical mineralisation of DOM in hypolimnetic than in epilimnetic water, irrespective from the small difference in the concentration of DOM, and in water seeping to the lake suggested that photolabile DOM in the epilimnion may slowly become depleted. The results support the hypothesis that photochemical degradation of DOM is an important and predictable factor in the carbon cycling of humic lakes. In addition, photochemical production of low molecular weight substances probably further enhances the mineralisation of DOM and deserves evaluation in humic lakes with a large pool of recalcitrant DOM.
Photochemical mineralisation of dissolved organic matter in lake Skjervatjern
AbstractPhotochemical mineralisation of dissolved organic matter (DOM) of a moderately humic lake was studied in 0.1 or 0.2 μm filtered water incubated in glass and quartz bottles. The direct measurement of mineralisation as an increase of dissolved inorganic carbon (DIC) proved to be a very useful tool when the concentration of DIC is low. At the lake surface, photochemical mineralisation was considerably higher in quartz than glass bottles indicating that UV light is the most important mineraliser of DOM. Because the glass bottles penetrated light well down to 340–350 nm wavelength, the photochemically most intensive part of solar radiation was in the range of UV-B. Higher photochemical mineralisation of DOM in hypolimnetic than in epilimnetic water, irrespective from the small difference in the concentration of DOM, and in water seeping to the lake suggested that photolabile DOM in the epilimnion may slowly become depleted. The results support the hypothesis that photochemical degradation of DOM is an important and predictable factor in the carbon cycling of humic lakes. In addition, photochemical production of low molecular weight substances probably further enhances the mineralisation of DOM and deserves evaluation in humic lakes with a large pool of recalcitrant DOM.
Photochemical mineralisation of dissolved organic matter in lake Skjervatjern
Salonen, K. (Autor:in) / Vähätalo, A. (Autor:in)
Environmental International ; 20 ; 307-312
16.02.1994
6 pages
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch
Photochemical mineralisation of dissolved organic matter in Lake Skjervatjern
| Online Contents | 1994
Microbial extracellular enzyme activities in Humex Lake Skjervatjern
| Elsevier | 1992
Periphyton investigations in HUMEX Lake Skjervatjern in 1992
| Elsevier | 1994
Microbial extracellular enzyme activities in Humex Lake Skjervatjern
| Elsevier | 1992
Soil-water interactions at the HUMEX Lake Skjervatjern
| Elsevier | 1992