The Distribution of Planktonic Protists Along a Latitudinal Transect in the Northeast Pacific Ocean

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(1)Ocean and Polar Research. Vol. 26(2):287-298. June 2004. Article. §ÿ ï·>ö* *êö 8 ¦F öÿ>~ ª

(2) ·Bê1*ÁR781ÁBë*2 ~&v ·" (402-751) Â7 Î Ï*ÿ 253 2 ·ö &~ãÁ¶ö¦ (425-600) ãVê nÖ nÖÖÚ ÒB 29^ 1. The Distribution of Planktonic Protists Along a Latitudinal Transect in the Northeast Pacific Ocean Eun Jin Yang1*, Joong Ki Choi1, and Woong-Seo Kim2 1. Department of Oceanography, Inha University Incheon 402-751, Korea 2 Marine Geoenvironment and Resources Research Division,/ KORDI Ansan P.O. Box 29, Seoul 425-600, Korea Abstracts : As a part of Korea Deep Ocean Study program, we investigated the distribution of planktonic protists in the upper 200 m of the northeast Pacific from 5oN to 17oN, along 131o30'W. Area of divergence was formed at 9oN which is boundaries of the north equatorial counter current (NECC) and the north equatorial current (NEC) during this cruise. Chlorophyll-a concentration was higher in NECC than in NEC area. Pico chl-a(<2 µm) to total chl-a accounted for average 89% in the study area. The contribution of pico chl-a to total chl-a was relatively high in NEC area than in NECC area. Biomass of planktonic protists, ranging from 635.3 to 1077.3 mgC m−2(average 810 mgC m−2), was most enhanced in NECC area and showed distinct latitudinal variation. Biomass of HNF ranged from 88.7 to 208.3 mgC m−2 and comprised 15% of planktonic protists. Biomass of ciliates ranged from 123.6 to 393.0 mgC m−2 and comprised 25% of planktonic protists. Biomass of HDF ranged from 407.2 to 607.8 mgC m−2 and comprised 60% of planktonic protists. HDF was the most dominant component in both NECC and NEC areas. Nano-protist biomass accounted for more than 50% of total protists in the both areas. The contribution of nanoprotist to total protists biomass was relatively higher in NEC area than in NECC. The biomass of planktonic protists was significantly correlated with phytoplankton biomass in this study area. The size structure of phytoplankton biomass coincided with that of planktonic protists. This suggested that the structure of the planktonic protists community and the microbial food web were dependent on the size structure of the phytoplankton biomass. However, biomass and size structure of planktonic protist communities might be significantly influenced by physical characteristics of the water column and food concentration in this study area. Key words : §ÿ ï·(Northeast Pacific Ocean), ¦F öÿb(planktonic protists), «³'· fÞÎ ~(heterotrophic dinoflagellates), RÎÏ~(ciliates), «³'· ²ÞÎ~(heterotrophic nanoflagellates). 1. B. . ·~ 'êöB ¦F öÿbf ²; 5 ² *Corresponding author. E-mail : [email protected]. ; ÿb2·Ê~ 7º W¶ «³'· ²ÞÎ ~, RÎÏ~, «³'· fÞÎ~, OÖÏ~, FÏ~ W>Ú ® (Stoecker and Capuzzo 1990). ¦F öÿ bf ·f Vf ç&'b ê&Ò ÿb ê~ ö.æ vªj /ê~, · V~ _.

(3) 288. Yang, E.J. et al.. ¢ Î"'b S~, 7;ÿb 2·Ê~ 7º _ ö >V r^ö · ê~ V&¦ö ^b _ " 7; ÿb2·Ê _j Ö~º ö.æ * " FVbî~ B~ö 7º j (Sieburth et al. 1978; Azam et al. 1983: Sheldon et al. 1986; Rassoulzadegan et al. 1988; Sherr et al. 1988). *;'b öÿ b~ bïf öB b2·Ê" FÒ ª¢ , · ¢¢ ¢N ÖK~ 10-70% 6º 100% çræ ²j~V r^ö · _~ ê²B~ö 7º ~² V (Pierce and Turner 1992). ß® §ÿ ï· " ?f n'· öB b2·Ê bïf 7; ÿ b2·Êö² Î"'b ÏF > ìº ² b 2·Ê(<2 µm)b W>Ú ®V r^ö &f j &~ n'· >öB ² b2·Êj Ï~º öÿb~ f " jvB ß® 7 º~² > ® (Sherr et al. 1986; Verity et al. 1996). §ÿ 'ê ï· æf ~~ ßWö V¢ B bÒ, z' ~ã ßWj ¾æÚº >b Bãb Ë ~º §'ê ~f ÿãb Ë~º 'ê >~& ¦' b ò¾ ãêöB æ' BÖj ;W~º > (Pickard and Emery 1982). f ? ~~ ßWö ~ >Z 5 BÖ~ ;Wf [>Zö '·" ³ê¢ Ã &Ê, ;rÒjf b2·Ê~ ÖKj ;zÎ. (Betzer et al. 1984; Chavez and barber 1987; Chavez et al. 1996; Hyun et al. 1998; Son et al. 2001). Bræ §ÿ ï·öB ¦F öÿbö & º 'ê ï·j 7b ~ þÒf ¢îö~ ç Vê& B®~ Vö 76'b Ò >îb, " b2·Êö & ²; ÿb2·Ê~ S" öÿb~ bïö & Ò& Ú r . ¾ ïjVö öÿb~ Î ÷j &çb º b² >î (Landry et al. 1995; Chavez et al. 1996; Verity et al. 1996; Brown and Landry 2003; Landry et al. 2003; Yang et al. 2003). Ò>f §ÿ ï· >~ §'ê >~&f § 'ê ~&¢ ~º >b ~~ ßWö V¢ B bÒ z' ßWj ¾æÞ (·>Ö¦ 2003). º §ÿ ï· >öB ~ö ~ >Z~ ß Wö V ¦F öÿb~ bï ªf ÷ö & ~ Ò~& . 6 ¦F öÿb" b2·Ê~ &ê¢ Û §ÿ ï· >~ ' êöB ¦F öÿb~ 7ºWö & ¢~~& .. 2. \O» Ò> B Òº. 2003j. 7ú. Korea. Deep. Ocean. Fig. 1. Map of study area showing location of sampling sites.. Study(KODOS) 03-3 öÒ V* ÿn §ÿ ï· 5oN17oNf 131o30'W *öB 1oN *Ïb C 13B ;6 öB >¯>îb, ' ;6f *êê ;6 N5-;6 N17 V~& (Fig. 1). Ò>~ ¢>' >ZßW f BË~ Î'ê ~& 5oN ÎöB ¾æ¾, ÿË~ §'ê >~º 5oN-10oNöB ¾æ¾, 10oN-30oN Ò öBº BË~ §'ê ~& ¾æÂ . 10oN¢ 7b ~ Îã" §ãb NF~ > pÚæ, b [f 10oN¢ 7b ~ §ãöBº »jæ Îã öBº pÚæº ßWj (Wyrtki and Kilonsky 1984). ÒV*öº Î'ê ~~ ßWj ;{~² "æº p~b, 9oNj 7b BÖ ;W>Ú 9oN~ Îã>öBº §'ê >~~ ßWj &, 9oN ~ §ã>öBº §'ê ~~ ßWj & . ¾ §'ê ~ö *~ 15oN~ 80 m pöB Ïß*ç ¢¦ B~&b, 14oN-15oNöBº æ'b 7 Î~ intrathermocline eddy& ¾æ¾º ßûj & ( ·>Ö¦ 2003). ¦F öÿb~ *ï ªC >[Ú öÿb~ bïj 2k~V *~ 0, 10, 20, 30, 50, 75, 100, 120, 150, 200 mf #² &[ (chlorophyll maximum layer)öB >¢ 1000 ml j>~ Lugol's b «³ê 1% >² ;~& . ;B òº þ Ú> öÿb~ &Vj * ò¢ 50 mlræ &¢p² ê S-R chamberf sedimentation chamber¢ ÒÏ~ 7 *ã(Nikon Type 104)" ; 7 *ê *ã(Olympus IX 70)b &V~& . «³' · ² ÞÎ~f ²; «³'· fÞÎ~(<20 µm)~ bïj 2k~V * 150 ml~ >¢ j>~ & ær~ «³ê 1%& >² ; ê ïÿ &~ þ Ú>~& . Ú>B ò 100-120 ml ¢ 0.45 µm nuclepore polycarbonate black filterf 5 µm.

(4) Planktonic Protists in the Northeast Pacific Ocean. nuclepore polycarbonate black filter '' "~ DAPI(Porter and Feig 1980) «³ê 5 µg ml−1& > ² "ï ê ;7*ã(Nikon type 104)j ÒÏ~ « ³ '·Wj ª~& . ¦F öÿb~ ê²ï *~8 «³'· ² ÞÎ~~ ê²ïf *ã~öB Ú'j ê Børsheim and Bratbak(1987)~ *~8 220 fgC µm−3j Ï~ ~& . öÿbf *ã ~öB ' ^ V¢ G; ê ^ Ï'j Edler (1979)~ O»ö V¢ ~& . F« RÎÏ~(tintnnnids) º carbon(pg) = 44.5 + 0.053 lorica volum(µm3)(Verity and Langdon 1984)~ ö V¢ ~&b, b' ìº n Î RÎÏ~(oligotrichs)º 0.19 pgC µm−3(Putt and Stoecker 1989)~ *~8j ÒÏ~ ~Ö~& . fÞÎ~~ ê² ïf Edler(1979)~ O»ö V¢ Ï'j ê MendenDeuer and Lessard(2000)~ þ Carbon(pg) = 0.216. 289. [volume, m3]0.939j Ï~ ' ^~ ê²ïj ~&. . OÖÏ~~ ê²ïf Michaels et al.(1995)~ j Ï~ G;~& . #²-a ³ê ' ;6~ 0, 10, 30, 50, 75, 100, 120, 150, 200 m f #² &[öB >¢ j>~ Turner Design Fluorometer(10-AU)¢ ÒÏ~ *ËöB G;~& . Vê #²-a ³êº PC membrane filter pape(2 µm pore size)¢ Ï~ VV¢ ê, 2 µm ~~ ² Vf 2 µm çb V¢ ª~& . V ê #²-a ³ê¢ G;~V *~ > 1000-2,300 ml ¢ Millipore "æ(0.45 µm pore size) " ê "æ¢ 90% j^Êö ~;ê ºÂ ê .&8j G ;~& . ò ªC 5 Ûê¾Ò. Fig. 2. Depth distribution of chlorophyll-a concentration and depth integrated chlorophyll-a along a latitudinal transect in the study area..

(5) 290. Yang, E.J. et al.. Ò>öB ¦FW RÎÏ~º b' ìº nÎ R ÎÏ~(oligotrichs)f b'j < ®º F« RÎÏ~ (tintinnids) ª~ ªC~& . «³'· fÞÎ~º ² Protoperidinium sp. ? b'j < ®º F' (thecate) fÞÎ~f Gyrodinium sp.f Gymnodinium sp. ?f b'j < ®æ pf Z'(athecate) fÞÎ~ ª~& . ' Ò~ æï ç&&ê ªCf ' ~ ;6ö V >ê bï 8j Ï~ SAS package(ver. 8.1) ªC~& .. 3. Ö. . #²-a ³ê #²-a ³êº Î ;6öB 0.518 µg l−1 ~~ ³ ê¢ & (Fig. 2). #² &[f ' ;6ê B. pöB ¾æÒb, &*êöB *ê .> pÚæº ãËj & . §'ê >~&ö *~ ;6 N5-N8öBº [ b[öB #² ³ê& ¸² ª ~& . ;6 N10 §~ *ê >öBº #² & [ 6N pÚæB >N£[" ¢~~º ·çj &. . > 120 mræ Ö >ZÚ #²-a ³êº ;6 N6öB 30.2 mg chl. m−2b &Ë ¸² ¾æÒb, N9 ¢ B~ *ê .> 6N Ôjæº ãËj &. . ÒV* ÿn Vê #²-a ³ê 7 ² # ²-a ³êº *Ú #²-a ³ê~ ï 89%¢ Næ~& b, §'ê >~&~ ;6 N5-N9öBº ï 82%, ; 6 N15¢ B §ãê ~&ö *~ ;6öBº ï 92% ç~ ¸f Ö6j & . ¦F öÿb~ *ï ª

(6) ¦F öÿbf «³'· ²ÞÎ~(Heterotrophic nanoflagellates; HNF), ¦FW RÎÏ~(Ciliates), «³' · fÞÎ~(Heterotrophic dinoflagellates; HDF), OÖÏ ~(Radiolaria) ª~& . Ò>öB «³'· ² ÞÎ~º &¦ª 2-5 µm W>Ú ®î . «³'· ²ÞÎ~~ *ïf 48-1,180 cells ml−1 ª~&b , ï 455 cells ml−1 ¾æÒ (Fig. 3). «³'· ² ÞÎ~~ >ç ªº [ b[öB jv' ¸f ª ¢ &b, #² &[ ~¦ ÚJ.> Ô² ª ~º ãËj & . ;6ê ªº ;6 N5f N6, Ò ;6 N11öB jv' ¸² ª~&b, ;6 N13, N14, N17öB Ôf ª¢ & . ¦F RÎÏ~~ * ïf 0.07-3.2 cells ml−1 ª~&b, ï 0.8 cells ml−1 ¾æÒ (Fig. 3). ¦F RÎÏ~~ >ç ªº ; 6 N5-N7~ [ b[ ¦"öB ¸f ª¢ &b¾, *ê >b .> #² &[ ¦"öB ¸² ¾. æÒ . ;6ê ª ßWf &*ê > ;6 N6öB &Ë ¸f ª¢ &, *ê > ;6 N17öB &Ë Ôf *ïj & . Ò>~ ¦F RÎÏ~ 7 &Ë Ö6~ ¾æÂ f nÎ RÎÏ~, 0.06 -2.9 cells ml−1 ª~&b, *ïf ;6 N16öB &Ë ¸² ¾æÒ . Ò>öB &VB nÎ RÎÏ~ ~ &¦ªf Strombidium spp., Strobilidium spp., Tontonia spp. b W >î . 6 F« RÎÏ~ f 0.2 cells ml−1 ~~ Ôf *ï ª¢ &b, ;6 N7 öB &Ë ¸² ¾æÒ . F« RÎÏ~~ «Wf & öB ¢>'b ª~ ®º R« b'j < º Rabdonella, Proplectella, Dadayiella, Petalotricha, Epiplocylis, Amphorella, Steenstrupiella, Eutintinus, Xystonellopsis, Undella, Dictyocysta, Salpingella b W>î . *Î~ f ¢¦ >öB Â*~& b¾ 0.05 cells ml−1 ~~ Ôf *ï 8j & . 6 20 µm ~~ ²; RÎÏ~º &¦ª nÎ RÎ Ï~ b ¾æÒb, ~ *ï ªº 0.011.6 cells ml−1(ï 0.4 cells ml−1) *Ú RÎÏ~ 7öB ï 40-63%(ï 52%)¢ Næ~& . *Ú RÎ Ï~ö ²; RÎÏ~~ VNf ;6 N6öB &Ë ¸~, ;6 17öB &Ë Ô~ . ²; nÎ~~ &¦ ªf Strombidium spp.f Strobilidium spp. " ª º ©b &V>î . «³'· fÞÎ~~ *ïf 2-62 cells ml−1 ª ~&b, ï 23 cells ml−1 ¾ æÒ (Fig. 3). «³'· fÞÎ~~ >ç ªº «³' · ²ÞÎ~ 5 RÎÏ~f FÒ~² &*ê ;6öB º [ b[öB ¸f ª¢ &b, *ê .> #² &[öB ¸f ª¢ & . ;6êº ; 6 N5f N6öB &Ë ¸f ª¢ &b, Ïß *ç ¾æÂ ;6 N9f ;6 N15öBê ² ¸² ¾æÒ. . «³'· fÞÎ~~ *ïf F' fÞÎ~ö j Z' fÞÎ~ö ~ ¸f ª¢ &b, Z' f ÞÎ~~ &¦ªf 20 µm ~~ ²; «³'· fÞ Î~ ©b &V>î . Z' fÞÎ~~ &¦ªf Gymnodinium spp.f Gyrodinium spp. W>Ú ®b , F' fÞÎ~~ &¦ªf Protoperidium spp. W >î . ¾ ;6 N15~ 80 mf N16~ 50 m~ > öB F' fÞÎ~ Protoperidinum sp.~ ¸f *ï f ß ò *çb &V>î . 6 OÖÏ~º &f j& öB 9² Â*~º b &¦ª b'·b W>Ú ® . f ;rÒj ¶, .¶, Ç¶, FV êJb¶b · '· O j . · 'êöB · « Â*~& æò, Ò>öB OÖÏ~~ *ïf 50 cells l−1 ~~ Ôf ª¢ , «³'· öÿb 7öB 7º~.

(7) Planktonic Protists in the Northeast Pacific Ocean. 291. Fig. 3. Depth distribution of abundance of heterotrophic nanoflagellates, ciliates and heterotrophic dinoflagellates along a latitudinal transect in the study area (Units: cells ml−1).. æ pf b ¾æÒ . ¦F öÿb~ `÷\ > 120 mræ Ö «³'· ²ÞÎ~~ bï f 88.7-208.3 mgC m−2(ï 120.4 mgC m−2) ª~ &b, «³'· ²ÞÎ~º ¦F öÿb~ 10-22% ¢ Næ~ ï 15%¢ V~º ©b ¾æÒ (Fig.. 4; Fig. 6). ¦F öÿbö «³'· ²ÞÎ~~ V Nf «³'· ²ÞÎ~~ bï &Ë ¸~~ ;6 N5öB &Ë ¸² ¾æÒ . RÎÏ~~ ê²ïf 123.6 -393.0 mgC m−2(ï 208.2 mgC m−2) ª~&b, *Ú ¦F öÿb~ 15-40%¢ Næ~, ï 25%¢ Næ~& (Fig. 4; Fig. 6). RÎÏ~7 nÎ RÎÏ~~.

(8) 292. Yang, E.J. et al.. Fig. 4. Carbon biomass of heterotrophic nanoflagellates, ciliates and heterotrophic dinoflagellates along a latitudinal transect in the study area.. bïf 62-90%¢ Næ~º ©b ¾æÒb, ;6 N6öB &Ë ¸f VNj & . F« RÎÏ~º R ÎÏ~ bï~ 0.7-13%¢ Næ~&b, ;6 N7öB &Ë ¸f VNj & . Î ;6öB nÎ RÎÏ~ º F« RÎÏ~ö j ï 8V ç~ ¸f bï ª¢ & . «³'· fÞÎ~~ bïf 407.2607.6 mgC m−2(ï 480.4 mgC m−2) ª~& (Fig. 4; Fig. 6). f *Ú ¦F öÿbö 55-65%¢ Næ ~, ï 60%¢ Næ~ ¦F öÿb7 &Ë Ö6~ º b ¾æÒ . 7 Z' «³'· fÞÎ~º 58% ç Ö6~& . ;6 N16öB F' «³'· fÞ Î~& ¦F öÿb~ 10% ç Ö6 ©j B. , Ò V* ÿn Â* Z' «³'· fÞÎ~º F ' «³'· fÞÎ~~ bïö j 20V ç ¸f. ©b ¾æÒ . OÖÏ~~ bïf 6.2-21.5 mgC m−2(ï 11.7 mgC m−2) ª~&b, ¦F ö ÿb~ ï 1.5%¢ Næ~& (Fig. 4; Fig. 6). «³' · ²ÞÎ~, RÎÏ~, «³'· fÞÎ~f OÖÏ~ ¢ ~º >ê ¦F öÿb~ bïf 0.47-18 µgC l−1(ï 5.8 µgC l−1) ª~& (Fig. 5). ¦F ö ÿb bï~ >ç ªº ;6 N5-N10öBº [ b[ ¦"öB ¸² ¾æÒb, *ê >b .> #² &[~ pf ¢~~º ·çj & . > 120 mræ Ö >ZÚ ¦F öÿb~ bïf 635.3-1077.3 mgC m−2(ï 810 mgC m−2) ¾æÒ. (Fig. 5). *Ú ¦F öÿb~ bïf §'ê >~&ö *~ ;6 N5, ;6 N6" ;6 N9öB &Ë ¸² ª ~&b, §'ê ~&ö *~ ;6 N17öB &Ë Ô.

(9) Planktonic Protists in the Northeast Pacific Ocean. 293. Fig. 5. Vertical distribution of planktonic protists biomass along a latitudinal transect in the study area (Units: µgC l−1).. Fig. 6. Carbon biomass of planktonic protists along a latitudinal transect in the study area. (A) is cumulative carbon biomass, (B) is relative percent of protists group and (C) is cumulative of protists size group..

(10) 294. Yang, E.J. et al.. Table 1. Pearson's correlation coefficients between heterotrophic protists and phytoplankton. NC PC HNF Ciliates HDF Radioraria Nanoprotists Microprotists Protists. TC 0.688*** 0.981*** 0.336** 0.547*** 0.460*** 0.335*** 0.435*** 0.579*** 0.528***. NC 0.536*** 0.080 0.239 0.301** 0.228 0.140 0.288** 0.208. PC. HNF. Ciliates. HDF. 0.368*** 0.573*** 0.488*** 0.330** 0.469*** 0.597*** 0.559***. 0.524*** 0.720*** 0.294** 0.823*** 0.549*** 0.798***. 0.629*** 0.232 0.635*** 0.940*** 0.806***. 0.212 0.971*** 0.687*** 0.956***. Radiolaria Nanoprotists Microprotists. 0.243** 0.295** 0.284**. 0.638*** 0.951***. 0.830***. Note: Significant correlation were defined as ***P<0.0001, **P<0.001 (TC, Total chlorophyll-a; NC, Net-nano chlorophyll-a (>2 µm); PC, Pico chlorophyll-a(<2 µm); HNF, Heterotrophic nanoflagellates; HDF, Heterotrophic dinoflagellates; Nanoprotists, HNF + <20 µm ciliates + <20 µm HDF; n=121).. f 8j & . ¦F öÿb b2·Ê~ ê ^b *~ ç^&ê¢ 2k~V *~ ¦F öÿb~ ' " Vê #²-a ³ê Òö ç& &ê¢ ªC~& (Table 1). *Ú ¦F öÿb~ b ï" #²-a ³ê Òöº ¸f ç&&ê¢ &b (R=0.53, p<0.0001), ¦F öÿb~ ' 5 Vê ÷f #²-a ³ê~ V Òöê ¸f ç&& ê¢ & . «³'· ²ÞÎ~f RÎÏ~º ² #²-af ¸f ç&&ê¢ &b, «³'· fÞÎ~ º 2 µm ç~ #²-a 5 ² #²-af ç&W ¸f ©b ¾æÒ . OÖÏ~º ² #²-af ç &W ®rj "î . 20 µm ~~ ²; öÿ bf ² #²-a ³êf ¸f ç&&ê¢ &b, 20 µm ç~ ²; öÿbf ² #²-a 5 2 µm ç~ #²-af Îv ç&W ®º ©b ¾æÒ . 6 öÿb ÷ Òöê ¸f ç&&ê¢ & .. 4. Æ. ~. §ÿ'ê ï· >f *;' n'· >b ~~ ßWö V¢ >Z& ª>, ~ Ç bÒ z' ~ãj ;W (Pickard and Emery 1982). ß® B ~ Fÿ" "V' Ïß *çb ~ >çb ;~² ;W>º 'ê ï· " > " >Z~ b £ W[zB §ï· ~~æ~ n;B >Zfº ßWj < ®b, bÒ' ~ã æzö ~ 2·Ê~ ÷º 'V ßWj (Wyrtki and Kilonsky 1984; Moum et al. 1989; Brown and Landry 2003). §ÿ ï·>öB *ö >¯B KODOS Òö ~~, §'ê ~(NEC)f § 'ê >~(NECC)~ ãêö *~ 8oN-10oN ÒöB. æ' BÖ ;W>, ~ >ç b[ » jæ, '·" ³¦ b [b Ïß>Ú "æ >ö b ÖKj ;zÎ (Hyun et al. 1998; · >Ö¦ 1999, 2003). 6 §'ê ~&ö *~ *ê >öBº ê.' >N£[j ;W~ >N£[ p Â] W[zB >Z¢ ;W~, '·" Ôf *; ' n'· ~ ßWj ¾æÞ (Son et al. 2001; ·>Ö¦ 2003). ÒV* ÿn §ÿ ï· >f § 'ê >~f §'ê ~& ò¾º 9oNöB Ïß *ç B~ Ò>~ >Zº bÒ, z' ßWö N ¢ &b, b2·Ê~ bï" ÷f >Zö V ¢ ßWj & (·>Ö¦ 2003). f ?f ~ã ßWö V¢ ÒV* ÿn Â* ¦F öÿb~ b ïf &*ê > ;6 N5-N9öB &Ë ¸² ª~& b, ;6 N9 §~ *ê .> Ôjæº ãËj & . V¢B §'ê ï·~ ¦F öÿb~ bï f [ b[ p, '·" ³¦ 'ê ¦"~ & *ê >öB ¸² ª~, W[z& Â]~² ;WB n'· ~ *ê >b .> 6N bï Ô ² ª~ §ÿ ï·öB *ö ÒB b2· Ê" öÿb ~ ªf FÒ ãËj & (Peña et al. 1990; Chavez et al. 1996; Landry et al. 1996; Liu et al. 1996; Brown and Landry 2003). 6 Ò>f 1998j¦V 2000jræ~ Ò¢ Û bÒ z' º ö ~ ^b ÷ æz¢ º >b ¾æÒ b, 1998j ÒöB öÿb~ bïf 'ê BÖ ;WB 8oN¢ 7b &*ê >b .> ¸~, *ê >b .> Ôjæº ãËj & (Yang et al. 2004). Ò >" ÿ¢ >öB Bræ~ Ò¢ Û §ÿ ï· >~ ¦F öÿb~ bï ªº bÒ' >Z ßWö ~ 'Ëj Aº ©b ¾æÒ (·>Ö¦ 1998, 1999, 2000)..

(11) 295. Planktonic Protists in the Northeast Pacific Ocean. ÒV* ÿn ¦F öÿb ÷f «³'· ² Þ Î~, RÎÏ~, «³'· fÞÎ~f OÖÏ~~ 4b ª~&b, 7 «³'· fÞÎ~º *Ú öÿ b~ 60%¢ Næ~ &Ë Ö6~º b ¾æÒ . «³'· fÞÎ~~ *ïf Ò>öB 1998jö ÒB 8ö j ² ¸² ¾æÒb¾(Table 2), *~ §ÿ 'ê ï· >öB ÒB Ö"f FÒ ·çj & (Chavez et al. 1996; Vørs et al. 1997). «³'· fÞÎ~~ bï ªº §'ê >~&ö *~ &* ê ;6öB ¸~b, ;6 N15¢ B~º §'ê . ~&ö *~ *ê ;6b .> Ô² ¾æÒ . ; 6 N15öB «³'· fÞÎ~~ jv' ¸f ªº ;6öB intrathermocline eddy æ' Ïß * ç B~ ~~ ³ê& ¸² ¾æÂ ©" &N ®º ©b 'B (·>Ö¦ 2003). «³'· fÞ Î~~ · ¯ÿf ·~ãöB b2·Ê~ S¶B ß® 7º~, ß® ~ öÿb7ö B 7º j ~º ©b >î (Sherr et al. 1997; Garrison et al. 1998; Levinsen et al. 1999). 1998j ÒöBê «³'· fÞÎ~~ bïf *Ú öÿb. Table 2. Comparisons of abundance and carbon biomass of planktonic protists reported in the equatorial Pacific Ocean. Region and protists. Month of year. Abundance (cells ml−1). Biomass (µgC l−1). Equatorial Pacific (0o, 140'W) <20 um flagellates February-April 2400 6 Dinoflagellates 24 1.3 Ciliates 0.06 0.08 <20 um flagellates August-October 1700 5.9 Dinoflagellates 29 1.8 Ciliates 0.09 0.16 Central and eastern tropical Pacific (12oN-10oS, 95oW, 110oW, 125oW, 140oW and 170oW) Heterotrophic flagellates Spring (Survey I) 647 ± 311 1.7 ± 1.3 Heterotrophic dinoflagellates 41 ± 13 2.3 ± 2.8 Aplastic ciliates 3.0 ± 2.6 1.5 ± 2.0 Heterotrophic flagellates Fall (Survey II) 772 ± 298 1.5 ± 0.7 Heterotrophic dinoflagellates 59 ± 20 3.1 ± 0.5 Aplastic ciliates 2.1 ± 2.6 1.3 ± 1.4 o o o o o o Equatorial Pacific (10 N-8 S, 110 W; 8 S-12 N, 125 W) Heterotrophic flagellates Spring 559 ± 249 1.4 ± 0.5 Chanoflagellates 25 ± 15 0.1 ± 0.1 Heterotrophic dinoflagellates 41 ± 12 3.0 ± 1.5 Ciliates 4±3 1.0 ± 0.7 Equatorial Pacific (5oN-9oN, 110oW) Heterotrophic flagellates November, 1988 6-110 Chanoflagellates 0-6 Heterotrophic dinoflagellates 11-40 Ciliates o o o Northequatorial Pacific (5 N-11 N, 130 30'W) Heterotrophic flagellates July, 1998 28-465 0.06-1.1 Heterotrophic dinoflagellates 2-46 0.3-4.0 Ciliates 0.01-1.7 0.03-2.9 Northequatorial Pacific (5oN-17oN, 131o30'W) Heterotrophic flagellates July, 2003 48-1180 0.09-3.1 Heterotrophic dinoflagellates 2-62 0.3-8.2 Ciliates 0.07-3.2 0.09-5.5. Reference. Verity et al. (1996). Chavez et al. (1996). Vørs et al. (1997). Chavez et al. (1990). Yang et al. (2003). This study.

(12) 296. Yang, E.J. et al.. ÷~ 50% çj Næ~º ©b ¾æÒb, § ÿ 'ê ï·~ ÒöBê «³'· fÞÎ~º ¦F öÿb~ 50% çj Næ~º ©b ¾æ¾ Ò ~ Ö"f ¢~~º ãËj & (Chavez et al. 1996; Vørs et al. 1997). ¦F öÿb7 RÎÏ~º «³'· fÞÎ~ rb 7º b ¾æÒ . ¦F RÎ Ï~~ *ï ªº §ÿ ï· >öB 1998jö ÒB *ïö j ² ¸² ¾æÒb¾ 'ê ï· >öB ÒB 2-3 cells ml−1(Chavez et al. 1996)f 4 cells ml−1(Vørs et al. 1997)ö j Ôf 8j &. (Table 2). RÎÏ~º *Ú öÿb~ ï 24%¢ Næ ~&b §'ê ~&ö *~ *ê ;6öB jv ' ¸f VNj & . &¦ª ·öB ¦FW RÎÏ ~º F« RÎÏ~ö j nÎ RÎÏ~ ö ~ 2 VöB 10Vræ z ¸f bï ª¢ (Pierce and Turner 1992). ÒöBê nÎ RÎÏ~~ bï f F« RÎÏ~ö j ï 8V ç ¸f ©b ¾ æÒ . ¦F öÿb7 «³'· ²ÞÎ~º ¦F ö ÿb~ ï 15%¢ Næ~&b, ;6 N5öB &Ë ¸f *ï" Ö6j & . «³'· ²ÞÎ~º ² 2·Ê~ 7º S¶B, ² 2·Ê ~ *ï ªf ¢~~ ¾æÂ (Christaki et al. 2001). ;6 N5öB «³'· ²ÞÎ~~ ¸f ªº ;6öB ;rÒjf Synechococcus~ ¸f *ï ª f &N ®º ©b ÒòB (·>Ö¦ 2003). Ò>öB &VB «³'· ²ÞÎ~~ *ïf 1998jö ÿ¢ >öB ÒB «³'· ²ÞÎ~ö j 2V ç ¸~b¾ §ï· >öB *ö Ò B 8" FÒ Ö"¢ & (Chavez et al. 1996; Vørs et al. 1997). ç~ ''~ öB BB ©" ? ¦F öÿb~ bïf §'ê >~&ö *~ &* ê >öB &¦ª ¸² ª ~&b, *ê >b .> Ôf ª¢ & . ¾ ;6 N9öB~ ¸f bïf Ïß*çb '·" ³ê~ Ã&f b2·Ê~ ¸f ªf & ®º ©b 'B . 6 öÿb~ >ç' ª ßWf &*ê > öBº [ b[öB ¸² ¾æÒb, *ê .> #² &[öB jv' ¸f ª¢ & . f ?f Ö"º ¦F öÿb~ bï ªº ¢N'b b·Ê~ bï" & ®º ©b 'B . n '· >öB «³'· öÿb~ bïf #²-a ³êf &7 &Nj <º ©b >î (Beers and Stewart 1971; Burkill et al. 1995; Dolan and Marrase 1995; Landry et al. 1995; Garrison et al. 1998). Ò>öB v Ò~ ç&&ê ªC Ö" ¦F öÿb" b2·Ê bï Òö ç&W ¸f ©b ¾æÒ. (Table 1). 6 ¦F öÿb~ 60% çj Næ~º ²; öÿb" ² #²-a Ò~ ¸f ç&& ê, ²; öÿb" ²; 5 ²; #²-a(>2 µm) Ò ~ ¸f ç&&ê, «³'· fÞÎ~f ²; 5 ²; #²-a(>2 µm) Ò~ ¸f ç&&ê, «³'· ²Þ Î~f ² #²-a Ò~ ¸f ç& &ê f . Òö &7 &ê& ®rj B . ß® § ï· >öB ² b2·Ê~ WËf ²; öÿb~ Sö ~ ² .>Úæ, ' ê ÚöB Ö" ²jº ;j ®º ©b ¾æÒ. (Verity et al. 1996). V¢B Ò>öB ¦F ö ÿb~ Vê ÷º b2·Ê~ Vê ª ·ç" FÒ ãËj &b, Ö"º ¦F öÿb " b2·Ê Òö b-¶~ &ê& ®rj z ~, b-~ &ê& ^b _öB 7º . º F > ®rj Ò . ÒöB ¢N' b ¦F öÿb~ bï ªf ÷¢ ÚÚ" r, ¦F öÿb~ bï" Vê ÷º *êö V¢ N¢ º ©b ¾æÒ . f ?f Ö"º ' >Z~ ßWö ~ ¢NÖ¶~ bï" Vê ª ·ç ² ¾æÒV r^ö b2·Êj _ Ï~º ¦F öÿb~ bï" Vê ÷ê " ç® ¢~~º ·çj ¾æÞ ©b ÒòB . §ÿ ï·" ? ² b2·Êö ~ Ö6 ~º >öB ¦F öÿbf >ö j~ ß ® 7º~, [öB b2·Êö ~ ÖB ê² ~ ôf ¦ª : b ;>º © º ' ê~ ^b _~ ê²B~ö 7º V¢ . (Stoecker et al. 1996; Hall et al. 1999). f ? ² b2·Ê Ö6~º n'· >öB ²; ÿb2· Êf ¢N Ö¶~ &Ë 7º ²j¶B ï· &>öB ²; ÿb2·Êf ¢¢ ¢N ÖK~ 70%ræ ²j~(Beers and Stewart 1971), 'ê ï· öBº ¢N ÖK~ 70-133%ræ ²j~(Verity et al. 1996), 1996j~ þÒ V*ö 'ê ï· >öB b2·Ê ÖK~ ï 69%¢ B~& (Landry et al. 2003). 6 Ò>" ÿ¢ >öB 1998j~ ¢îö Vö ÒB ¦F öÿbf b2·Ê~ 85-140%ræ B~º ©b ¾æÒ (Yang et al. 1998). Ö"º Ò>~ ' êöB öÿbf _ /~ æzö ² >w~V r^ö Ö" ²j Òö ; ®º &ê& Fæ>º ©b 'B . ¾ ÒV* ÿn b2·Êö & öÿb~ S &ê& Ò>æ p~V r^ö öÿb~ 7ºWö &~ ;{~² ¢~ >º ì . ¾ 1998j~ ¢ îö V*ö >¯B ¶òö "¢ v(Yang et al. 2003),.

(13) Planktonic Protists in the Northeast Pacific Ocean. ¦F öÿb~ bï 5 Vê ÷f b2· Ê Vê bï Ò~ &7 &êö &~ J " r, §ÿ ï· >~ ' êöB ^b f Ö" ²jÒö ; couplingj ;W~ ¦ F öÿbf ^b _ ÚöB FV ê²~ * ¶B 7º j © . ¾ ^b _ ÚöB ¦F öÿb~ ê²~ Ï" *f >Z ~ ßWö V¢ ² ¾æ¾V r^ö ¦F öÿb~ ê >Z~ ßWö V¢ N& ®j ©b ÒòB . 6 Ò>f 1996j¦V þÒf ¢îö ~ ç Vê *çb ~ ôf ~ã æz¢ º · ê² B~" &NB 7º > . V¢B ' êöB ¦F öÿbö & æ³' ¢ Û Ë V' ^b ÷~ bï æzf ÷~ Ö6ê, Ò b2·Êö & öÿb~ S{ö & & ÖF'b ÒB , Ëê * æ ~ã æzö V §ï· >öB · ê~ æz ·ç" ê² B~j ~º 7º ¶òB ÏF © .. Ò. Ò. ¢^j ^&~² Ò" vª~ Ò*öþ ê b 6Òãî . 6 ¢ >¯~º ®Ú * Ë ·ë" ò¾Òö êæj & f~ Nf '" N, Ò N*Ò^ FËþ ~ * ßö ª" &¶öbV öö²ê 6Òãî . º ·>Ö¦ R&D "B ‘& 7b¶ö öÒÒ ë’~ j æöö ~~ >¯>îÛî .. ^^ò ·>Ö¦. 1998. '98 & 7b¶ö öÒ B(1). · >Ö¦ B, 1209 p. ·>Ö¦. 1999. '99 & 7b¶ö öÒ B(1). · >Ö¦ B, 780 p. ·>Ö¦. 2000. 2000 & 7b¶ö öÒ B(1). ·>Ö¦ B, 594 p. ·>Ö¦. 2003. 2003 & 7b¶ö öÒ B(1). ·>Ö¦ B, 770 p. Azam, F., T. Fenchel, J.G. Field, F.S. Gray, and L.A. Meyer-Reil. 1983. The ecological role of water-column microbes in the sea. Mar. Ecol. Prog. Ser., 10, 257-263. Beers, J.R. and G.L. Stewart. 1971. Microzooplankton in the plankton community of the upper waters of the Eastern Tropical Pacific. Deep-Sea Res., 18, 861-883. Betzer, P.R., W.J. Showers, E.A. Laws, C.D. Winn, G.R.. 297. DiTullio, and P.M. Kroopnick. 1984. Primary productivity and particle fluxes on a transect of the equator at 153oW in the Pacific Ocean. Deep-Sea Res., 31, 1-11. Børsheim, K.Y. and G. Bratbak. 1987. Cell volume to cell carbon conversion factors for a bacterivorus Monas sp. enriched from sea waters. Mar. Ecol. Prog. Ser., 36, 171175. Brown, S.L. and M.R. Landry. 2003. Microbial community abundance and biomass along a 180o transect in the equatorial Pacific during an El niño-Southern oscillation cold phase. J. Geophys. Res., 108, 8139. Burkill, P.H., E.S. Edwards, and M.A. Sleigh. 1995. Microzooplankton and their role in controlling phytoplankton growth in the marginal ice zone of the Bellingshausen Sea. Deep-Sea Res. II, 42, 1277-1290. Chavez, F.P. and R.T. Barber. 1987. An estimate of new production in the Equatorial Pacific. Deep-Sea Res., 34, 1229-1243. Chavez, F.P., K.R. Buck, S.K. Service, J. Newton, and R.T. Barber. 1996. Phytoplankton variability in the central and eastern tropical Pacific. Deep-Sea Res. II, 43, 835-870. Christaki, U., A. Giannakourou, F. Wambeke, and G. Gregori. 2001. Nanoflagellates predation on auto-and heterotrophic picoplankton in the oligotrophic Mediterranean Sea. J. Plankton Res., 23, 1297-1310. Dolan, J.R. and C. Marrase. 1995. Planktonic ciliates distribution relative to a deep chlorophyll maximum: Catalan Sea, N.W. Mediterranean, June 1993. Deep-Sea Res., 42, 1965-1987. Edler, L. 1979. Phytoplankton and chlorophyll recommendations for biological studies in the Baltic Sea. Baltic Marine Biologists, p. 13-25. Garrison, D.L., M.M. Gowing, and M.P. Hughes. 1998. Nano-and microplankton in the northern Arabian sea during the southwest Monsoon, August-September, 1995 A US-JGOFS study. Deep-Sea Res. II, 45, 2269-2299. Hall, J.A., M.R. James, and J.M. Bradford-Grieve. 1999. Structure and dynamics of the pelagic microbial food web of the subtropical convergence region east of New Zealand. Aqua. Microb. Ecol., 20, 95-105. Hyun, J.H., J.K. Choi, E.J. Yang, and K.H. Kim. 1998. Biomasss and productivity of bacterioplankton related to surface water divergence in the Northeast Equatorial Pacific Ocean. J. Microbiol., 36, 151-158. Landry, M.R., J. Constantinou, and J. Kirshtein. 1995. Microzooplankton grazing in the central equatorial Pacific during February and August, 1992. Deep-Sea Res. II, 42, 657-671. Landry, M.R., J. Kirshtein, and J. Constantinou. 1996..

(14) 298. Yang, E.J. et al.. Abundance and distribution of picoplankton populations in the central equatorial Pacific from 12oN to 12oS, 140oW. Deep-Sea Res. II, 43, 871-890. Landry, M.R., S.L. Brown, J. Neveux, D. Dupouy, J. Blanchot, S. Christensen, and R.R. Bidigare. 2003. Phytoplankton growth and microzooplankton grazing in high-nutrient, low-chlorophyll waters of the equatorial Pacific: Community and taxon-specific rate assessment from pigment and flow cytometric analysis. J. Geophys. Res., 108, 8142. Levinsen, H., T.G. Nielsen, and B.W. Hansen. 1999. Plankton community structure and carbon cycling on the western coast of Greenland during the stratified summer situation. II. Heterotrophic dinoflagellates and ciliates. Aquat. Microb. Ecol., 16, 217-232. Liu, D., G.A. Fryxell, and I. Kaczmarska. 1996. El Niño (1992) in the equatorial Pacific: low biomass with a few dominating in the microphytoplankton. J. Plankton Res., 18, 1167-1184. Menden-Deuer, S. and E.J. Lessard. 2000. Carbon to volume relationships for dinoflagellates, diatoms and other protist plankton. Limnol. Oceanogr., 45, 569-579. Michaels, A.F., D.A. Caron, N.R. Swanberg, F.A. Howse, and C.M. Michaels. 1995. Planktonic sarcodines(Acantharia, Radiolaria, Foraminifera) in surface waters near Bermuda: abundance, biomass and vertical flux. J. Plankton Res., 17, 131-163. Moum, J.N., D.R. Caldwell, and C.A. Paulson. 1989. Mixing in the Equatorial surface layer and thermocline. J. Geophys. Res., 94, 2005-2021. Peña, M.A., M.R. Lewis, and W.G. Harrison. 1990. Primary productivity and size structure of phytoplankton biomass on a transect of the equator at 135oW in the Pacific Ocean. Deep-Sea Res., 37, 295-315. Pickard, G.L. and W.J. Emery. 1982. Descriptive physical oceanography, 4th ed. Pergamon Press. 249 p. Pierce, R.W. and J.F. Turner. 1992. Ecology of planktonic ciliates in marine food webs. Rev. Auat. Sci., 6, 139-181. Porter, K.G. and Y.S. Feig. 1980. The use of DAPI for identifying and counting aquatic microflora. Limnol. Oceanogr., 25, 943-948. Putt, M. and D.K. Stoecker. 1989. An experimentally determined carbon: Volume ratio for marine “oligotrichous” ciliates from estuarine and coastal waters. Limnol. Oceanogr., 34, 1097-1103. Rassoulzadegan, F., M. Laval-Peuto, and R.W. Sheldon. 1988. Partitioning of the food ration of marine ciliates between pico-and nanoplankton. Hydrobiologia, 159, 75-88. Sheldon, R.W., P. Nival, and F. Rassoulzadegan. 1986. An experimental invesigation of a flagellate-ciliate-copepod. food chain with some observations relevant to the linear biomass hypothesis. Limnol. Oceanogr., 31, 184-189. Sherr, E.B., B.F. Sherr, and G.A. Paffenhofer. 1986. Phagotrophic protozoa as food for metazoans: a ‘missing’ trophic link in marine pelagic food webs? Mar. Microb. Food Webs, 1, 61-80. Sherr, E.B. and B.F. Sherr. 1988. Role of microbes in pelagic food webs: a revised concept. Limnol. Oceanogr., 33, 1225-1227. Sherr E.B., B.F. Sherr, and L. Fessenden. 1997. Heterotrophic protists in the central Arctic ocean. Deep Sea Res. II, 44, 1665-1682. Sieburth, J.McN., V. Smetacek, and J. Lenz. 1978. Pelagic ecosystem structure: heterotrophic components of the plankton and their relationship to plankton size fractions. Limnol. Oceanogr., 23, 1256-1263. Son, S.K., J.H. Hyun, C.K. Park, S.B. Chi, and K.H. Kim. 2001. Characteristics of chemical environment by changing temperature at the surface layer in the northeast Equatorial Pacific. J. Kor. Soc. Mar. Environ. Eng., 4, 24-37. Stoecker, D.K. and J.M. Capuzzo. 1990. Predation on protozoa: its importance to zooplankton. J. Plankton Res., 12, 892908. Stoecker, D.K., D.E. Gustafson, P.G. Verity, and M.E. Sieracki. 1996. Micro- and meso-protozooplankton at 140oW in the equatorial Pacific: heterotrophs and mixotrophs. Aquat. Microb. Ecol., 10, 273-282. Verity, P.G. and C. Langdon. 1984. Relationships between lorica volume, carbon, nitrogen and ATP content of tintinnids in Narragansett Bay. J. Plankton Res., 6, 859-868. Verity, P.G., D.K. Stoecker, M.E. Sieracki, and J.R. Nelson. 1996. Microzooplankton grazing of primary production at 140oW in the Equatorial Pacific. Deep-Sea Res. II, 43, 1227-125. Vørs, N., K.R. Buck, F.P. Chavez, W. Eikrem, L.E. Hansen, J.B. Stergaard, and H.A. Thomsen. 1997. Nanoplankton of the equatorial Pacific with emphasis on the heterotrophic protists. Deep-Sea Res. II, 42, 585-602. Wyrtki, K. and B. Kilonsky. 1984. Mean water and current structure during the Hawaii-to-Tahiti shuttle experiment. J. Phys. Oceanogr., 14, 242-254. Yang, E.J., J.K. Choi, and J.H. Hyun. 2004, The distribution and structure of heterotrophic protists communities in the northeast equatorial Pacific Ocean. Mar. Biol., In press. Received Apr. 16, 2004 Accepted May 29, 2004.

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