INVESTIGADORES
MASSAFERRO Julieta
artículos
Título:
Paleolimnological records of carotenoids and carbonaceous particles in sediments of some lakes in Southern Alps
Autor/es:
LAMI; GUILIZZONI; MARCHETTO; MASSAFERRO
Revista:
HYDROBIOLOGIA
Editorial:
SPRINGER
Referencias:
Lugar: Berlin; Año: 1994 vol. 274 p. 57 - 64
ISSN:
0018-8158
Resumen:
Stratigraphic analyses of organic carbon, organic nitrogen and algal and bacterial carotenoids in short
cores of profundal sediments of four alpine lakes (Tovel, Leit, Paione superiore and Tom) were used
to reconstruct their trophic history. In addition, depth distribution of carbonaceous particle concentrations
provided information on lake contamination from atmospheric deposition.
In three lakes (Tovel, Leit and Tom), sedimentary carotenoids unique to sulfur photosynthetic bacteria
(okenone and isorenieratene) provide evidence of changes in the oxygen, light and sulfide conditions
in the water column. All the lakes are oligotrophic or moderately productive, and the algal community
is dominated by Chlorophyta, Pyrrhophyta and Cryptophyta. Cyanobacteria are rather poorly
represented.
The steep increase of carbonaceous particles in the uppermost sediment layers of all the lakes suggests
that lake contamination by atmospheric transport of pollutants began in the 1940s to 1950s. These
data, coupled with those from a parallel study on Chrysophycean scale-inferred pH, indicate recent
acidification in those which are poorly buffered (Paione superiore and Leit).