Epilithic algae in a glacial stream at Hope Bay (Antarctica)

The epilithic algal community of a glacial stream of Hope Bay (Antarctica) was studied during the summer period of 1995. Major hydrological changes, which affected the main physical and chemical features, were observed in the stream according to the meltwater pulses. The enrichment of the stream by...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Izaguirre, I., Pizarro, H.
Formato: JOUR
Materias:
algae
community composition
cyanobacteria
epilithic algae
glacial stream
meltwater
Antarctica, Hope Bay
Chrysophyceae
Hydrurus foetidus
Phaeogloea mucosa
Phormidium fragile
Prasiola crispa
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_07224060_v19_n1_p24_Izaguirre
Aporte de:
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires
id todo:paper_07224060_v19_n1_p24_Izaguirre
record_format dspace
spelling todo:paper_07224060_v19_n1_p24_Izaguirre2023-10-03T15:36:53Z Epilithic algae in a glacial stream at Hope Bay (Antarctica) Izaguirre, I. Pizarro, H. algae community composition cyanobacteria epilithic algae glacial stream meltwater Antarctica, Hope Bay Chrysophyceae Hydrurus foetidus Phaeogloea mucosa Phormidium fragile Prasiola crispa The epilithic algal community of a glacial stream of Hope Bay (Antarctica) was studied during the summer period of 1995. Major hydrological changes, which affected the main physical and chemical features, were observed in the stream according to the meltwater pulses. The enrichment of the stream by seabird inputs was evident from the high nutrient concentrations and their increase downstream. The presence of a snowbank in the middle reach produced a major discontinuity, influencing the main variables analyzed. The stream showed a similar algal composition to other water courses of Hope Bay, with Prasiola crispa, Hydrurus foetidus, Phaeogloea mucosa and Phormidium fragile as the dominant species. Chlorophyll a concentrations taken from natural substrata (stones) ranged from undetectable to 48.4 mg m-2, with the maximum concentrations associated with algal mats dominated by Prasiola crispa. with signs of enrichment by seabirds, and Prasiola crispa as one of the dominant algal species. Other similarities with either continental or maritime Antarctic streams include the presence of filamentous cyanobacteria (Hirano 1979; Broady 1982; Howard-Williams et al. 1986; Hawes 1989; Hawes and Brazier 1991). Nevertheless, the stream also showed the occurrence of an unusual flora of Chrysophyceae, very abundant in some reaches. Later studies carried out in other streams of Hope Bay have revealed a similar algal composition (Pizarro and Vinocur, in press). In the present study the epilithic algal community of one of the most important glacial streams of Hope Bay is described. Some of the most important physical and chemical variables regulating algal growth are discussed. Fil:Izaguirre, I. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Pizarro, H. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_07224060_v19_n1_p24_Izaguirre
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic algae
community composition
cyanobacteria
epilithic algae
glacial stream
meltwater
Antarctica, Hope Bay
Chrysophyceae
Hydrurus foetidus
Phaeogloea mucosa
Phormidium fragile
Prasiola crispa
spellingShingle algae
community composition
cyanobacteria
epilithic algae
glacial stream
meltwater
Antarctica, Hope Bay
Chrysophyceae
Hydrurus foetidus
Phaeogloea mucosa
Phormidium fragile
Prasiola crispa
Izaguirre, I.
Pizarro, H.
Epilithic algae in a glacial stream at Hope Bay (Antarctica)
topic_facet algae
community composition
cyanobacteria
epilithic algae
glacial stream
meltwater
Antarctica, Hope Bay
Chrysophyceae
Hydrurus foetidus
Phaeogloea mucosa
Phormidium fragile
Prasiola crispa
description The epilithic algal community of a glacial stream of Hope Bay (Antarctica) was studied during the summer period of 1995. Major hydrological changes, which affected the main physical and chemical features, were observed in the stream according to the meltwater pulses. The enrichment of the stream by seabird inputs was evident from the high nutrient concentrations and their increase downstream. The presence of a snowbank in the middle reach produced a major discontinuity, influencing the main variables analyzed. The stream showed a similar algal composition to other water courses of Hope Bay, with Prasiola crispa, Hydrurus foetidus, Phaeogloea mucosa and Phormidium fragile as the dominant species. Chlorophyll a concentrations taken from natural substrata (stones) ranged from undetectable to 48.4 mg m-2, with the maximum concentrations associated with algal mats dominated by Prasiola crispa. with signs of enrichment by seabirds, and Prasiola crispa as one of the dominant algal species. Other similarities with either continental or maritime Antarctic streams include the presence of filamentous cyanobacteria (Hirano 1979; Broady 1982; Howard-Williams et al. 1986; Hawes 1989; Hawes and Brazier 1991). Nevertheless, the stream also showed the occurrence of an unusual flora of Chrysophyceae, very abundant in some reaches. Later studies carried out in other streams of Hope Bay have revealed a similar algal composition (Pizarro and Vinocur, in press). In the present study the epilithic algal community of one of the most important glacial streams of Hope Bay is described. Some of the most important physical and chemical variables regulating algal growth are discussed.
format JOUR
author Izaguirre, I.
Pizarro, H.
author_facet Izaguirre, I.
Pizarro, H.
author_sort Izaguirre, I.
title Epilithic algae in a glacial stream at Hope Bay (Antarctica)
title_short Epilithic algae in a glacial stream at Hope Bay (Antarctica)
title_full Epilithic algae in a glacial stream at Hope Bay (Antarctica)
title_fullStr Epilithic algae in a glacial stream at Hope Bay (Antarctica)
title_full_unstemmed Epilithic algae in a glacial stream at Hope Bay (Antarctica)
title_sort epilithic algae in a glacial stream at hope bay (antarctica)
url http://hdl.handle.net/20.500.12110/paper_07224060_v19_n1_p24_Izaguirre
work_keys_str_mv AT izaguirrei epilithicalgaeinaglacialstreamathopebayantarctica
AT pizarroh epilithicalgaeinaglacialstreamathopebayantarctica
_version_ 1807321929683566592

Ejemplares similares