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The effects of enriching Sargasso Sea water on the production and species composition of phytoplankton
Oceanographic Abstracts
499
Institute of Oceanography in Great Britain, and the Isaacs--Kidd midwater trawl. One such station was o,,er the Cariaco Trench, Venezuela; another over adjacent but open waters of the Caribbean. At each, two samples werc obtained : the first from 0 to 400 m depth, the second 400 to about 600 m. The deep haul at the Trench station fished anoxic waters and the catch was meagre save for a large number of Bre~'macero.Y atlanticus, a fish which should be examined for physiological or anatomical adaptions to anaerobic existence. The catch from similar depths north of the sill was in no respect unusual. Although both shallow hauls fished waters in part amenable to pelagic life, they differed in the nature if not the number of fishes caught. It is suggested that certain groups o f fishes and perhaps larger invertebrates as well are compelled to migrate vertically diurnally, a fatal instinct for an animal de~'ending to the anoxic and sulphurous waters of the Cariaco Trench. Confirmation is needed: the single Trench station should be repeated many times. Notes on species identity and distribution are givcn, and Scopelent, ys w&oi is described as new. MLxzF.t. I). W., E. M. IIt:t.BURT and J. H. RY'n~R, 1963. The effects o f enriching Sargasso Sea water on the production and species composition of phytoplankton. Deep-Sea Res., 10 (3): 209-219. The technique of artiticial enrichment of sea water has been used in an attempt to define nutrients critically limiting the growth of phytoplankton in the Sargasso Sea. It is shown that final population growth achieved with different enrichment is a function of time. In 3 day experiments, iron appeared essential while the 7 day experiments nitrogen and phosphorus alone produced large populations. It is postulatcd that the influence of iron may be catalytic since enrichment with aluminium produced identical growth curves. In addition the final population resulting from enrichment in terms of species composition was shown to be a function o f the addition of specific nutrients. MEWRS S. P., W. A. FF.DeR and K. MON TSUE, 1963. Nutritional relationships among certain Iilamcntous fungi and a marine nematode. Science, 141 (3580): 520-522. •~ marinc form of nematode, /tphelenchoides sp., can develop and reproduce effectively on viable mycelia of various filamentous fungi including certain widespread marine species. The efficiency of utilization of fungal mycclium by the animal, based on the ratio of the number of nematodes '.o the dry weight of fungal mucelium, varies greatly among fungi, from less than 100 to as much as 5000 for several of the marine species studied. MOLLER .I.T., 1963. Vadehavet mellem mando og Ribe/~. Folia Geograph. Danica, 8 (4): 40 pps. A description of a survey of the salt-march foreland and the tidal-flats directly to the south of Ribe ,~, on the southwest coast of Jutland. The survey was carried out during the summer 1961 by the Geographical Institute at the University of Copenhagen on behalf of ' De Danske Vade- og Marskundcrsogclscr " (The Danish Wadden and Salt-Marsh Investigations). The survey is a continuation of tile mapping in I : 10OO0 of the Danish Wadden Sea. Further a description of the morphology in the surveyed area and of the tidal-area o f Knudedyb (map in 1 : 75000), and the results of a ~esearch on the spread of Spartina townsendii and the influence of this plant on the morphologic :~rocesscs in the Danish Wadden Sea is given. Mt'LFORt~ R. A., 1963. Distribution of the dinoflagellate genus Ceratium in the tidal and offshore watcrs of Virginia. Chesapeake Sci., 4 (2): 84-89. Distribution of thc genus ('cratium in lower Chesapeake Bay and adjacent offshore waters of the Atlantic Ocean is described. Of thirteen species listed, four (C. lineaturn, ('. trichoceros, C. massi/tense. and ('. am'ticunt) ha',c not been previously recorded in the lower bay. Most species represent warm-temperate or tropical forms which culminate in an autumn community. As a whole the genus becomes progrcssitcly more important proceeding offshore from upper estuarine conditions. Temperature and salinit) ranges observed for each species are reported. NAC,TK;',t.I.K. I1"., 1962. 0 b e r die Regclung von Langquarzcn in aquatisch sedimentierten ~anden. ,'~f~Tniana, 1 2 : 9 -24. Dic Orienticrung ~.on Langquarzen, die unter dem Einfluss eincr Wasserstr/Smung sedimentiert wurdcn, werdcn in 47 Regelungsanalysen untersucht. Die statistischc Auswertung tier Richtungsmessungcn crgibt, dass dic Langachsen der Langquarze in zwei aufeinander senkrecht stehenden R.iclltungen gcregclt sind .-. parallel und quer zur Str6mungsrichtung. Nach dem Antcil an quergeregeltcn Langquarzc, werden zwci Regelungstypen unterschieden : die L/.ings-Regelung mit %-36 pro zent und die l~ings-Quer-Regelung mit 36-72 pro zent quergeregelten l.angquarzen. L~ngs()t,er-Rcgclung w.urde vor allcm auf frischen Sandoberft;,ichen beohachtet, w~ihrend die LtingsR.egchmg insbesondcrc im Schichtvcrband gefunden wurdc, tmd zwar sowohl in Strandsanden als auch ill fluviatilcn Sanden. Durch die Lage polarer QuarzkOrner lasst sich in beiden Regelungstypen tier SIr~imungssinn bestimmcn. Die Entstehung zweier verschiedener Regelungstypen wird darauf zuriickgeftihrt, dass bei unterschiedlich hohcr Gcschwindigkeit des striSmenden Wassers die Transportform und der Regelungsvorgang \erschicden sind. Die aus strOrendcn Einfltissen wLihrend der Sedimentation und dcr vcrschicdcnartigen Entstchung tier Regelungstypcn resultierenden Fehlerm/Sglichkeiten bei der Ausdcutung tier Regclung in fossilcn Sanden wcrdcn aufgczeigt.
499
Institute of Oceanography in Great Britain, and the Isaacs--Kidd midwater trawl. One such station was o,,er the Cariaco Trench, Venezuela; another over adjacent but open waters of the Caribbean. At each, two samples werc obtained : the first from 0 to 400 m depth, the second 400 to about 600 m. The deep haul at the Trench station fished anoxic waters and the catch was meagre save for a large number of Bre~'macero.Y atlanticus, a fish which should be examined for physiological or anatomical adaptions to anaerobic existence. The catch from similar depths north of the sill was in no respect unusual. Although both shallow hauls fished waters in part amenable to pelagic life, they differed in the nature if not the number of fishes caught. It is suggested that certain groups o f fishes and perhaps larger invertebrates as well are compelled to migrate vertically diurnally, a fatal instinct for an animal de~'ending to the anoxic and sulphurous waters of the Cariaco Trench. Confirmation is needed: the single Trench station should be repeated many times. Notes on species identity and distribution are givcn, and Scopelent, ys w&oi is described as new. MLxzF.t. I). W., E. M. IIt:t.BURT and J. H. RY'n~R, 1963. The effects o f enriching Sargasso Sea water on the production and species composition of phytoplankton. Deep-Sea Res., 10 (3): 209-219. The technique of artiticial enrichment of sea water has been used in an attempt to define nutrients critically limiting the growth of phytoplankton in the Sargasso Sea. It is shown that final population growth achieved with different enrichment is a function of time. In 3 day experiments, iron appeared essential while the 7 day experiments nitrogen and phosphorus alone produced large populations. It is postulatcd that the influence of iron may be catalytic since enrichment with aluminium produced identical growth curves. In addition the final population resulting from enrichment in terms of species composition was shown to be a function o f the addition of specific nutrients. MEWRS S. P., W. A. FF.DeR and K. MON TSUE, 1963. Nutritional relationships among certain Iilamcntous fungi and a marine nematode. Science, 141 (3580): 520-522. •~ marinc form of nematode, /tphelenchoides sp., can develop and reproduce effectively on viable mycelia of various filamentous fungi including certain widespread marine species. The efficiency of utilization of fungal mycclium by the animal, based on the ratio of the number of nematodes '.o the dry weight of fungal mucelium, varies greatly among fungi, from less than 100 to as much as 5000 for several of the marine species studied. MOLLER .I.T., 1963. Vadehavet mellem mando og Ribe/~. Folia Geograph. Danica, 8 (4): 40 pps. A description of a survey of the salt-march foreland and the tidal-flats directly to the south of Ribe ,~, on the southwest coast of Jutland. The survey was carried out during the summer 1961 by the Geographical Institute at the University of Copenhagen on behalf of ' De Danske Vade- og Marskundcrsogclscr " (The Danish Wadden and Salt-Marsh Investigations). The survey is a continuation of tile mapping in I : 10OO0 of the Danish Wadden Sea. Further a description of the morphology in the surveyed area and of the tidal-area o f Knudedyb (map in 1 : 75000), and the results of a ~esearch on the spread of Spartina townsendii and the influence of this plant on the morphologic :~rocesscs in the Danish Wadden Sea is given. Mt'LFORt~ R. A., 1963. Distribution of the dinoflagellate genus Ceratium in the tidal and offshore watcrs of Virginia. Chesapeake Sci., 4 (2): 84-89. Distribution of thc genus ('cratium in lower Chesapeake Bay and adjacent offshore waters of the Atlantic Ocean is described. Of thirteen species listed, four (C. lineaturn, ('. trichoceros, C. massi/tense. and ('. am'ticunt) ha',c not been previously recorded in the lower bay. Most species represent warm-temperate or tropical forms which culminate in an autumn community. As a whole the genus becomes progrcssitcly more important proceeding offshore from upper estuarine conditions. Temperature and salinit) ranges observed for each species are reported. NAC,TK;',t.I.K. I1"., 1962. 0 b e r die Regclung von Langquarzcn in aquatisch sedimentierten ~anden. ,'~f~Tniana, 1 2 : 9 -24. Dic Orienticrung ~.on Langquarzen, die unter dem Einfluss eincr Wasserstr/Smung sedimentiert wurdcn, werdcn in 47 Regelungsanalysen untersucht. Die statistischc Auswertung tier Richtungsmessungcn crgibt, dass dic Langachsen der Langquarze in zwei aufeinander senkrecht stehenden R.iclltungen gcregclt sind .-. parallel und quer zur Str6mungsrichtung. Nach dem Antcil an quergeregeltcn Langquarzc, werden zwci Regelungstypen unterschieden : die L/.ings-Regelung mit %-36 pro zent und die l~ings-Quer-Regelung mit 36-72 pro zent quergeregelten l.angquarzen. L~ngs()t,er-Rcgclung w.urde vor allcm auf frischen Sandoberft;,ichen beohachtet, w~ihrend die LtingsR.egchmg insbesondcrc im Schichtvcrband gefunden wurdc, tmd zwar sowohl in Strandsanden als auch ill fluviatilcn Sanden. Durch die Lage polarer QuarzkOrner lasst sich in beiden Regelungstypen tier SIr~imungssinn bestimmcn. Die Entstehung zweier verschiedener Regelungstypen wird darauf zuriickgeftihrt, dass bei unterschiedlich hohcr Gcschwindigkeit des striSmenden Wassers die Transportform und der Regelungsvorgang \erschicden sind. Die aus strOrendcn Einfltissen wLihrend der Sedimentation und dcr vcrschicdcnartigen Entstchung tier Regelungstypcn resultierenden Fehlerm/Sglichkeiten bei der Ausdcutung tier Regclung in fossilcn Sanden wcrdcn aufgczeigt.