| one publication added to basket [1199] | Patrones fenologicos reproductivos de una poblacion de Gigartina skottsbergii (Gigartinaceae, Rhodophyta) en Ancud, Chile = Reproductive phenologic patterns of a population of Gigartina skottsbergii (Gigartinaceae, Rhodophyta) from Ancud, Chile
Avila, M.; Núñez, M.; Candia, A.; Norambuena, R. (1997). Patrones fenologicos reproductivos de una poblacion de Gigartina skottsbergii (Gigartinaceae, Rhodophyta) en Ancud, Chile = Reproductive phenologic patterns of a population of Gigartina skottsbergii (Gigartinaceae, Rhodophyta) from Ancud, Chile. Gayana Oceanol. 5(1): 21-32
In: Gayana Oceanológica. Universidad de Concepcion. Facultad de Ciencias Naturales y Oceanograficas: Concepción. ISSN 0716-9655, more
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| Authors | | Top |
- Avila, M.
- Núñez, M.
- Candia, A.
- Norambuena, R.
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| Abstract |
The reproductive phenologic patterns of Gigartina skottsbergii, in a bed at SanAntonio (41 degree 52'S; 73 degree 51'W), Bahia Ancud, Chiloe, were studied. Monthly samples were carried out during 18 months, in two transectsperpendicular to the shore. We quantified the biomass, wet weight (g/m super(2)),density (number of fronds/m super(2)) and size frequency (%) in vegetative andreproductive thalli of this species. We evaluated the natural spore recruitment onartificial substrates settled in the bed. A continuous diminution was observed withtime both of the biomass and the density of fronds of red "luga". The biomassreached a maximum value of 140 g/m super(2) in July (winter) and values below40 g/m super(2) in the summer months. Frond density is variable throughout theyear, values fluctuate between 5 fronds/m super(2) in the winter months and earlysummer and 2 fronds/m super(2) at the end of spring. Results on the sizefrequency indicated that individuals under 1 cm in size predominated in the bed throughout the study period and scarce fronds greater than 41 cm were found.Cystocarpic and tetrasporic fronds were observed in all four seasons of the year,but the greater abundance of reproductive plants occurred during fall and winter,coinciding with the greater abundance and maturity of the reproductive structures,cystocarps and tetrasporangial sori. Ploidy analysis by the resorcinol methodallowed to establish a clearcut seasonality in the presence of gametophyte phase(more abundant in winter-spring) and tetrasporophyte phase (more abundant inlate summer-autumn). The results indicate that this bed, that is under anthropicactivity, presented scarce recovery of biomass in spring-summer periods, and alsoa high predominance of small thalli under 1 cm. |
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