The changes in macrozoobenthos were analyzed during January of 1997 lo July 01 1998 in Catarindo station (Mollendo-Arequipa) located at 17°01'13" LS and 72°02'19" LW. The samples were analyzed with a van Veen dredge 01 0,04 m2 to 34 m depth. A total of 50 different species, correspond to polychaete, mollusks, crustacean and others, were recorded; there were an increase of mollusks and crustacean species in 1998 which were absent in 1997. During "El Niño 1997-98" polychaete towered over numerically, being the most important species Prionospío peruana, Nephtys multícirrata, Goniada sp. and Leitoscoloplos chilensis. The major macrozoobenthos density was recorded in spring of 1997, and part of summer 1998, corresponding to P. peruana. The biomass fluctuated and the highest value corresponded to the polychaete group in 1997, but in 1998, the biomass increase corresponded to mollusk group...

The changes in macrozoobenthos were analyzed during January of 1997 lo July 01 1998 in Catarindo station (Mollendo-Arequipa) located at 17°01'13" LS and 72°02'19" LW. The samples were analyzed with a van Veen dredge 01 0,04 m2 to 34 m depth. A total of 50 different species, correspond to polychaete, mollusks, crustacean and others, were recorded; there were an increase of mollusks and crustacean species in 1998 which were absent in 1997. During "El Niño 1997-98" polychaete towered over numerically, being the most important species Prionospío peruana, Nephtys multícirrata, Goniada sp. and Leitoscoloplos chilensis. The major macrozoobenthos density was recorded in spring of 1997, and part of summer 1998, corresponding to P. peruana. The biomass fluctuated and the highest value corresponded to the polychaete group in 1997, but in 1998, the biomass increase corresponded to mollusk group...

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The present work 01 "El Niño" effect on annual cycle 01 phytoplankton was carried out among January of 1997 and September 01 1998. The samples were obtained two times by month with a Niskin bottle to 0,5 m depth in a station located at 17°00'56"lS and 72°02'15" LW. The Uthermol's method modified was followed for the analysis. The major phytoplanktonic density was recorded in summer of 1997 with values range between 3335 and 21 705 cel x 50 mL associated to predominance of the silicollagellate Dyctiocha fibula, which in February represented 76% 01 total density. A great decrease 01 phytoplankton density was recorded since June of 1997 until January 01 1998 (50 to 688 cel x 50mL) characterizing oligotrophic conditions associated to positive deviations of temperature that reached in January-98 4,9°C upon normality. This produced an interruption of the spring upwelling and altering the p...

The present work 01 "El Niño" effect on annual cycle 01 phytoplankton was carried out among January of 1997 and September 01 1998. The samples were obtained two times by month with a Niskin bottle to 0,5 m depth in a station located at 17°00'56"lS and 72°02'15" LW. The Uthermol's method modified was followed for the analysis. The major phytoplanktonic density was recorded in summer of 1997 with values range between 3335 and 21 705 cel x 50 mL associated to predominance of the silicollagellate Dyctiocha fibula, which in February represented 76% 01 total density. A great decrease 01 phytoplankton density was recorded since June of 1997 until January 01 1998 (50 to 688 cel x 50mL) characterizing oligotrophic conditions associated to positive deviations of temperature that reached in January-98 4,9°C upon normality. This produced an interruption of the spring upwelling and altering the p...