INVESTIGADORES
GOMEZ Nora
artículos
Título:
Structural Characteristics and Oxygen Consumption of the Epipelic Biofilm in Three Lowland Streams Exposed to Different Land Uses
Autor/es:
SIERRA M.V,; GÓMEZ N.
Revista:
WATER AIR AND SOIL POLLUTION
Editorial:
Springer
Referencias:
Lugar: Amsterdam; Año: 2007 vol. 185 p. 115 - 127
ISSN:
0049-6979
Resumen:
Abstract The structural features and O2 consumption
of the epipelic biofilm in streams of the Pampean
plain were explored. The study was conducted in
three lowland streams subjected to different anthropic
disturbances. Three sampling sites were selected in
different sectors of these streams considering land use
intensity (high, moderate, and low). Samples of the
water and of the epipelic biofilm were taken seasonally.
El Pescado stream is subjected to a low level of
human impact and showed lower organic matter and
nutrient contents than the Rodríguez and Don Carlos
streams which are subjected to moderate and high
levels of human impact. The biofilm composition of
the three streams was represented by cyanophytes and
diatoms but with different species composition and
dominance; protozoans and nematodes were the
characteristic heterotrophic groups in the three
streams. The Rodríguez and Don Carlos streams
showed the highest abundance of organisms. Multiple
regression showed that O2 consumption, chlorophyll
a and trophic index were significantly correlated with
the oxygen demands. On the other hand, the Rodríguez
and Don Carlos streams exhibited significant differences
with the El Pescado stream in O2 consumption trophic index,
and chlorophyll a content. Our results demonstrated that
the different biological descriptors responded to environmental
variables that are influenced by the different land use intensities,
being chlorophyll a, abundance of organisms, and O2 consumption
the most sensitive variables to the changes
water quality.
Keywords Epipelon . Pampean plain .Water quality .
Anthropogenic disturbance . Biological descriptors