Surface data of the Peru-Chile Current, relative abundance of diatoms, supplement to: Romero, Oscar E; Hebbeln, Dierk (2003): Biogenic silica and diatom thanatocoenosis in surface sediments below the Peru-Chile Current: controlling mechanisms and relationship with productivity of surface waters. Marine Micropaleontology, 48(1-2), 71-90

• Main Authors: Romero, Oscar E, Hebbeln, Dierk
• Format: Dataset
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2003
• Subjects: Event label; Latitude of event; Longitude of event; Elevation of event; DEPTH, sediment/rock; Achnanthes sp.; Actinocyclus curvatulus; Actinocyclus exiguus; Actinocyclus octonarius; Actinoptychus senarius; Actinoptychus vulgaris; Adoneis pacifica; Amphora ostrearia; Amphora sp.; Asteromphalus arachne; Asteromphalus flabellatus; Asteromphalus heptactis; Asteromphalus hyalinus; Asteromphalus sarcophagus; Aulacoseira granulata; Aulacoseira islandica; Azpeitia africana; Azpeitia barronii; Azpeitia neocrenulata; Azpeitia nodulifera; Azpeitia tabularis; Bacteriastrum elongatum; Bacteriastrum furcatum; Bacteriastrum hyalinum; Biddulphia alternans; Catacombas gailloni; Chaetoceros affinis; Chaetoceros bacteriastroides; Chaetoceros concavicornis; Chaetoceros decipiens; Chaetoceros diadema; Chaetoceros didymus; Chaetoceros didymus var. protuberans; Chaetoceros messanensis; Chaetoceros affinis, resting spores; Chaetoceros cinctus, resting spores; Chaetoceros compresus, resting spores; Chaetoceros constrictus, resting spores; Chaetoceros coronatus, resting spores; Chaetoceros debilis, resting spores; Chaetoceros diadema, resting spores; Chaetoceros didymus, resting spores; Chaetoceros lorenzianus, resting spores; Chaetoceros radicans, resting spores; Chaetoceros socialis, resting spores; Chaetoceros vanheurckii, resting spores; Chaetoceros sp., resting spores; Cocconeis britannica; Cocconeis californica var. lengana; Cocconeis costata var. costata; Cocconeis costata var. hexagona; Cocconeis decipiens; Cocconeis dirupta; Cocconeis pelta; Cocconeis placentula; Cocconeis pseudomarginata; Cocconeis speciosa; Cocconeis stauroneiformis; Corethron sp.; Coscinodiscus argus; Coscinodiscus centralis; Coscinodiscus janischii; Coscinodiscus coculus-iridis; Coscinodiscus radiatus; Coscinodiscus thorii; Ctenophora sp.; Cyclophora sp.; Cyclotella litoralis; Cyclotella meneghiniana; Cyclotella stelligera; Cymbella sp.; Delphineis surirella; Denticula sp.; Diatoma sp.; Diploneis bombus; Diploneis constricta; Dytilum brightwelli, resting spores; Epithemia sp.; Eunotia sp.; Fallacia nyella; Fragilariopsis doliolus; Gomphonema sp.; Grammatophora marina; Hannaea sp.; Hantzschia amphyoxis; Haslea hyalinissima; Hemialus sinensis; Hemidiscus cuneiformis; Leptocylindrus mediterraneus; Lioloma elongatum; Luticola mutica; Mastogloia rostrata; Navicula cryptotenella; Navicula distans; Navicula sp.; Neidium sp.; Nitzschia bicapitata; Nitzschia interruptestriata; Nitzschia sicula; Nitzschia sp. Nitzschia cf. sicula; Nitzschia sp.; Odontella longicruris; Opephora sp.; Paralia sulcata; Pinnularia borealis; Pinnularia microstauron; Planktoniella sol; Pleurosigma directum; Pleurosigma planctonicum; Proboscia alata; Proboscia alata forma indica; Psammodictyon panduriforme; Pseudohimantidium pacificum; Pseudostaurosira brevistriata var. inflata; Pseudo-nitzschia inflatula var. capitata; Pseudosolenia calcar-avis; Pseudotriceratium punctatum; Rhizosolenia acuminata; Rhizosolenia bergonii; Rhizosolenia borealis; Rhizosolenia pungens; Rhizosolenia styliformis; Rhopalodia sp.; Roperia tessellata; Skeletonema costatum; Stauroneis anceps; Stellarima stellaris; Stephanodiscus astraea; Stephanopyxis sp.; Surirella sp.; Synedra ulna; Tabularia sp.; Thalassionema bacillare; Thalassionema frauenfeldii; Thalassionema nitzschioides var. nitzschioides; Thalassionema pseudonitzschioides; Thalassionema nitzschioides var. inflata; Thalassionema nitzschioides var. parva; Thalassiosira aestivalis; Thalassiosira anguste-lineata; Thalassiosira bioculata; Thalassiosira conferta; Thalassiosira delicatula; Thalassiosira eccentrica; Thalassiosira endoseriata; Thalassiosira ferelineata; Thalassiosira gerloffii; Thalassiosira gravida; Thalassiosira lineata; Thalassiosira mendiolana; Thalassiosira minuscula; Thalassiosira nanolineata; Thalassiosira oestrupii var. oestrupii; Thalassiosira oestrupii var. venrickae; Thalassiosira pacifica; Thalassiosira plicata; Thalassiosira poro-irregulata; Thalassiosira punctifera; Thalassiosira rotula; Thalassiosira sackettii forma plana; Thalassiosira subtilis; Thalassiosira symmetrica; Thalassiosira tumida; Thalassiosira sp.; Trachyneis aspera; MultiCorer; Counting, diatoms; SO101; SO102/1; SO102/2; SO156/1; SO156/2; SO156/3; Sonne; Geosciences, University of Bremen GeoB; Antarctic; Pacific; Romero; Antarc*
• Online Access: https://dx.doi.org/10.1594/pangaea.80222; https://doi.pangaea.de/10.1594/PANGAEA.80222

Based on 76 surface sediment samples collected between ca. 22° and 44°S along the Chilean coast in the southeast Pacific Ocean, we report on the north-south distribution of opal content and diatom concentration, and the quantitative and qualitative composition of the preserved diatom community. Latitudinal differences in the siliceous signal reflect the influence of two main mechanisms of surface water production: coastal upwelling off northern and central Chile till ca. 38°S, and nutrient enrichment by the input of cold, southern, non-upwelling-associated waters south of ca. 38°S. The poleward increase in biogenic opal and diatom values parallels well the north-south increase of pigment concentration in surface waters as recorded by satellites. Between 22° and 33°S, where low pigment concentrations are measured, opal content and diatom concentration are mostly low (except at 22°-23°S). In contrast, both higher opal and diatom values at 34°-38°S and 41°-42°S correspond well with higher pigment estimations. Preserved diatom populations document the present-day dominant hydrographical conditions. Nutrient enrichment of surface waters due to coastal upwelling results in intensive production of diatoms off northern and central Chile, reflected by the predominance of the richly-composed association of Chaetoceros spores north of ca. 38°S. The diatom association shows that the area between 35° and 38°S is transitional. The abrupt decrease of Chaetoceros spores south of not, vert, similar38°S off Chile coupled with the enhanced contribution of Thalassiosira spp., representatives of high-productivity, low-temperature waters, points to the presumed high nutrient supply by the iron-limited, nutrient-rich Antarctic Circumpolar Water. The contribution of benthic diatoms reflects some lateral transport from the near-shore area into deeper positions south of 38°S.