Document 2RKRLbEp04dxXVmxvqx2oJB8g

. ..... vector 8) (2) where the numeric#! cnefiicic..,s arc taken from equation ,i;. Similar))', the tree-growth anomaly pattern correspond ing to the year following a high percentage of albaeore caught north of San Francisco can -be represented as: map 2>=8.56 (eigenvector 4)-6.17 (eigenvector 9) + 11.54 eigenvector 10) (3) These maps arc presenled in Fig. 4. The ring-width data were mostly from trees sited in arid localities, so that a wide ring would generally be associated with anomalously cool, cloudy weather and above normal precipitation whereas a narrow ring would reflect warm, sunny and dry conditions. . Below normal tree growth in the Pacific North-west (Fig. 4) is indicative of dry conditions associated with below normal cyclonic activity during the fishing season. Sunny and mild weather would favour albacore fishing ' in adjacent waters, as would above normal insolation regard less of weather. The resulting excess of stored heat in the ocean would be given up through evaporation during the following autumn and winter and lead to increased cyclonic activity and precipitation along the coast north of San Francisco. These conditions would lead to increased tree growth during the following growing season (Fig. 4). Autumn and winter climatic anomaly features, com bined with spring climate and the year-to-year autocorrela tion of tree-ring widths, produce the other ring-width anomaly features in Fig. 4 for the following growing season. Narrow ring widths south of San Francisco, for example, imply below normal precipitation--an expected feature since winter precipitation in the Pacific North-west is negatively correlated with winter precipitation in southern California*. The reconstructed values of albacorc catch distribution data (Fig. 3) and inferred population distribution also seem to exhibit long term changes over intervals of 100 yr or more, which suggest the possibility that long term fluctua tions in the occan-atmosphere system may be involved. The success of the calibration of tree-rings with albacore catch indicates the possibility of relating tree-ring varia tions to any type of biological variations which are affected by large scale climatic fluctuations. Such relationships may be quantified and used to reconstruct objectively other climatically-caused biotic variations in <he past. N. E, Clark National Oceanic anti Atmospheric Administration, National Marine Fisheries Service, Southwest Fisheries: Center, La Jolla. California 92037 T. 3. Blasiko H. C. Fkitts Laboratory of Tree-Ring Research, University of Arizona, Tucson, Arizona 85721 Kcccitcd Ocamtef 5. (974; tctejntd May 6,197$. * U\Ut<H. V. C.. Sch'mr, ft!. tft4.UJ04t (1974). * J , Mon. Wrath. Art.. U.S. /><*. Agrts.. 97. I7J. 192 11969). * Lu<t. R. M., rl *(., Arpvtt of Jutnt AV/rWn/ Ptvrine FltArf/rt Srrrtir-ArticrfcuA i'tihrun*ni fifitHtnk rumuUnktn Aihmmr Shttfirt ('nnJt/itrii Pttnnf /P?/ (Nntoni Metiac Fiiltcfici Service, Southwest t nheiic* Center, Lt JolU, 191$). 4 Cltmtiu, H, ft., end Cralft, W. L., Calif, Dtpt fiih ami Gtt*ue. fiik OmU., |2t (1965). * Sene. O. L.. Cuhf. Coup. Otranh /7th. /rnrif. Arpi. 7, IK-194 (1940), * IVW. C- II . Ah iHuHfRvtfa* *>f tottir ptfnpiltuhn ptti/rrht in CutifoiRf anti til/atefa trfion* (UimcuMy at California Water Rcvoyrcev Ctfttct, 1946). *`iay y w better in water depleted in v^ygen 18.attd deuterium While growing oats at different temperaiurev in w.aicr ol diifeiem "O and deuterium (D) abundances, wc noticed-that oats grown in Antarctic water in which is depleted in >`0 and D by -49%.and -400%,, relative to standard mean ocean water (SMOW used as a comparative reference in hydrogen and oxygen isotope studies), showed initial growth l-J weeks sooner than did oats grown in water containing greater "o and D concentrations. The oats seemed to grow belter in water which was most depleted in the stable isotopes throughout the growth period, The oats were grown from the same batch of seeds in two sealed glass-covered glass jars (approximately 10 I). Twenty- five oat seeds were added to each jar, containing the same amount of vermlculite and 500 ml water to which 5.0 g Bapid. Cro, a commercial fertiliser, had been added. One jar contained mclled glacial ice front t he Antarctic with isotopc concenira tions of -49%, 60 (SMOW) and -400%. 6D (SMOW). The other jar contained distilled ocean water with 4 1.0%, 5"0 (SMOW) and 4 17%. 6D (SMOW). Both jars were placed in the chamber at the tame time. - 'Theexperiment was repeated three times with new materials: once the growth chamber was maintained between 1.7 and 3.3 C; once between 24 and 26.6 *C; and once the temperature fluctuated between 1.7 and 26.6 `C. Each time-lhe oats in the jar containing water depleted in the heavy isotopes showed germination 1-2 weeks earlier and seemed to grow better throughout the growth period, than oats grown in distilled ocean water. Using oats grown at 15 !C, the first sign of germination`in the jar containing water depleted in the heavy isotopes was 4 d after planting. On the day 6, eight plants (out of 25) had attained a height of 6 cm. The first sign of germination in the jar with water containing the heavier isotope concentration, was after 17 d. By the time five plants had attained a height of 6 cm in this jar, in that with water depleted in the isotopes, 23 plants that had reached the top of the jar (approximately^ cm). Kashutin1 observed (hat snow-water depleted in D increases the yield of cucumbers, radishes and spring-wheat compared with controls grown in ordinary water of unspecified isotopic composition. He cites experiments on the egg productivity of hens and the weight gain of suckling pigs, in both cases water depleted in D was especially efficient in promoting productivity. Although much has been done on the effect of D-enriched water on biological systems, we suggest that research on the effect D-depIcted water on plant and animal growth may prove fruitful. A major source of water depleted in D by over 400"i, (40%) compared with SMOW is snow and ice from the Antarctic polar plateau. Water depleted by ISO-180%, is readily available in the USA from Rocky Mountain snow precipitating above 10,000 feet elevation. US Geological Survey, Denver, Colorado 80225 Jim D. Gleason Ikvinc Friujman Received February 10; accepted June ), 197$. f tUitiutfn, K,, Mroifo (VSSA). SB, 107 (1969). Identification of chlorinated dibenzofurans in American polychlorinated biphenyls Mortality of embryos has contributed to the reproductive failures of several bird species, including the sparrow hawks [Arcipiter nisus) of southern Scotland1, the white-tailed eagles (lialiaeeltts albicilln) of Schleswig Holstein', and the herring 019294 NEW 727349 water_PCB-SD0000035046 306 gulls {l.artn aryriitnttii) of Luke Ontario*. Suspected causes include (2,2-/m-(p-clilorophen),l)-l,l-dichloroethy- kne), other chlorinated biocides and/or their derivatives, and the polychlorinated biphenyls (rcils). all of which are picwnt as contaminants in the eggs'-5. PCBs are present in high concentrations in the bird populations which suffer embryonic mortality1-*. Other orgunoehlorine compounds which may be present in food webs include the chlorinated dibenzodioxins nnd the chlorinated dibenzofurans (Fig. 1), which are toxic to embryos in amounts'-' less than 1 pg. They arc therefore among the most toxic substances known and are possible causes of the observed mortality. The chlorinated dibenzodioxins and chlorinated dibenzo- furnns, however, have proved exceedingly difficult to detect in environmental samples in the concentrations at which they arc expected to be cmbryotoxic'-10. The chlorinated diben- zodioxins enter the environment as contaminant s in preparations of the herbicide 2,4,5-T (refs 5 and J J) and tire fungicide pcntnchlorophenol1*-1*. Chlorinated dibenzofurans have been found in a French (l'henoelor DP6) and a German fClophen AnOj PCB and were shown to be the active cmbryotoxic agent in these preparations'. The techniques used, however, did not detect chlorinated dibenzofurans in an American PCB, Aroclor 1260. We report here the presence of chlorinated dibenzofurans in Aroclor PCB, widely used in North America and Great Britain, and in the same Aroclor 1260 preparation examined previously with negative findings'. ' Samples of PCB examined include: Aroclor 1248, J254, and 1260 (1969); Aroclor 1254 (1970); Aroclor 1016 (1972); and die same three preparations studied by Vos ct a/.': Aroclor 1260, lot No. AK-3; Clophen A-60, lot No. 912434; and Phcnoclor DP-6, lot not specified. The latter three PCBs were obtained from Dr Vos, the others from the Monsanto Company in the years indicated in parentheses. PCBs extracted from environmental samples most often have gas chromatographic profiles similar to those of PCB formula tions containing approximately 48, 54 or 60% chlorine. In the Aroclor series, the former two -PCBs are equivalent to Aroclor 1248 and Aroclor 1254, respectively. Aroclor 1260, Phcnoclor DP6, and Clophen A60 all contain approximately 60% chlorine. Chlorinated dibenzofurans were identified in all Aroclor preparations except Aroclor 1016, as well as in Clophen A60 nnd Phcnoclor DP6. Aroclor 1016 is a PCB mixture containing Fig. 1 Skeletal structures of: a, chlorinated biphenyl, x-y -- 1-10; b, chlorinated dibenzofurans, x-f y " 1-8; c, chlorinated dibcuzcdiuxins, x+/ = 1-8. Nature Yal. ?S6 July JJ /<j7 <, Table 1 Chlorinated dibenzofuian concentrations* in Arovtor _____ Clophen and Phcnoclor ' PCB 4-CI 5-01 6-CT 1 otxl Aroclor 1248(1969) Aroclor 1254 (1969) Aroclor 1254 (1970) Aroclor 1260.(1969) Aroclor 1260 (lot. AK3) Aroclor 1016 (1972) Clophen A-60 Phcnoclor DP-6 0.5 (25) 0.1 (6) 0.2(13) 0.1 (10) 0.2 (25) ND 1.4 (17) 0.7 (5) 1.2 (60) 0.3 (15) 0.2(12) 1.4 (R2) 0.4 (27) 0.9 (6(1) 0.4 (40) 0.5 (50) 0.3 (38) 0.3 (38) NO ND 5.0 (59) 2.2 (26) 10.0 (74) 2.9 (21) 20 1.7 15 1.0 08 ._ 8.4 13.6 Expressed as pgg*1 PCB. Values in parentheses represent quantity as percentage total dibenzofttran. NO, not delected (<0.00l pa g*1). Amounts of PCB ranging front J.O to 2.0 g were dissolved in 400ml hexane, placed on a Plorisil column (180 g. internal diameter 31.5 ntnt), and eluted with: an additional 1,600 ml hexane, anil successive 800 ml volumes each of 5% diethyl-cther-hcxanc, 25% dfcthyl-elher-hexanc and acetone, at a rate of approximately 7 nil min-'.Themajor portion of the PCB was eluted in the hexane fraction, which was discarded. On addition of the.5% mixture, the clualcs were ,collccted in-six successive 4(0 ml volumes. To eliminate the polar solvents, each dilate was evaporated twice just to dryness and taken up each time in a minimal amount of hexane. Each fraction, in 1 nil hexane, was placed on a microalumina column" and eluted with 10 ml each of I % and 20% methylene chloride in hexane. These were also taken twice just to dryness and made to up a volume of I ml in hexane to eliminate the methylene chloride before gas chromato graphic analysis. Aliquots of all fractions obtained before and after partitioning on alumina were- injected into a six foot glass column containing 3%OVI on 100-120 mesh Supelcoport in Tracor MT220 and Hewlett-Packard 5700 gas chromatographs equipped with "Ni electron-capture detectors. PCBs were found to be present in each fraction eluted from the Ftorisil column in amounts sufficient to interfere with the detection of trace contaminants. Partitioning on the alumina columns separated most of the PCB interference into the I % methylene chloride fractions. On removal of this interference, different peak patterns appeared in the chromatograms of the 20% methylene chloride fractions. Compounds eluting in the 20% methy lene chloride fraction were collected for mass spcctrometric analysis using a 20:1 effluent splitter, and a trap consisting of a capillary tube (I mm internal diameter, 100 mm long) bent to a U shape, immersed in a liquid nitrogen batn. Methylene chloride (20%; 4 pi) in hexane was injected into the capillary as a rinse, removed with a 1.0 (it microptpelte, and placed directly on the mass spectrometer probe. The probe was inserted into a GF.C AF.I MSV02 high resolution mass spectrometer and the solvent removed by the force pump. 1 he probe was rapidly inserted into the ion source and multiple scans were recorded in the on-line high resolution mode". approximately 42% chlorine and has replaced Aroclor 1242 in many applications, principally as the dielectric fluid in capacitors". Values reported in Table 1 represent the total of those compounds found in 400 ml FJorisil fractions 2-6. A total of 10-12 isomers was identified in each PCll. Two chlorin ated dibenzofuran contaminants have been reported for the Clophen and Phenoclor previously*; our first analyses of the Clophen revealed an additional five chlorinated dibenzofurans*. The structures contained four to six chlorine atoms. Other diben zofurans including those chlorinated to a lesser extent may have been present in the first 400 ml fraction but this was not examined in detail as it contained substantial PCB interference. Recently synthesised 2,3,7,8-tetra-, 2,3,4,7,8-pemn- and 2,3,4,6,7.8hexachlorodibenzofuran were used to quantify tetra-, penta-, and hexachlorodibenzofurans, respectively. The former two authentic standards had retention times on the CAM column the same as those of two dibenzofurans isolated from the PCB Vos et at.1 detected no chlorinated dibenzofurans in an Aroclor 1260 preparation at a detection limit of 1 p.p.m. Fractionation and examination of the identical Aroclor 1260 in our study confirm their findings based on the stated limit, but reveal the presence of 11 chlorinated dibenzofurans in (tie preparation, having a total concentration of 0.8 jig g ' PC'!! (Table 1). Tlte same workers also found diethyl ether extracts of the Clophen A60 and Phenoclor DP6 to be much more toxic to chick embryos than diethyl ether extracts of Aroclor 1260. Our study confirms those findings on the basis of chlotinaied 727350 WATER PCB-SD0000035047 biuiurc Vo!. 2J6 July 24 1975 b -`nT^-'T-rp-p11 ~>V ~l tT`t-|^-r.-T-^r VT-T*4..rr'T " 150 200 250 300 350 l-'ig. 2 a, Gas chromatogram of a fraction of Aroclor 1254 containing n mixture of chlorinated biphenyls, dibenzofurans, amt naphthalenes. Identities of peaks ore given in the text. 6, Mass spectrum of peak 2, a tetrachlorodibenzofuran. dibenzoftiran content: the identical Clophcn and Phenoclor contain II and 17 times more total chlorinated dibenzofurans, respectively, titan the Aroclor 1260. A gHs chromatogram showing components derived from the Aroclor 1254 obtained in 1969 is represented in Fig. 2. The components were eluted in the Second 400 ml Florisil fraction and rocoveted front the alumina column in 20% methylene chloride-hexane. Each of the numbered peaks was trapped as described here, and identified by mass spcctrontetric analysis. A nominal mass plot of the high resolution mass spectrum of peak 2 is shown in Fig. 2. The plot includes all the ions with elemental compositions ranging to the maximum empirical formula C,lf,0,`CI,,,Ci4',C,. The molecular ion cluster nt nominal m/e 304-310 fragments by successive losses of Cl to yield the ions at m/e 269-275 and CO to the ions at m/e 241-245. A minor loss of Cl front the peaks at m/e 269 -275 also occurs to yield the tons at m/e 234 -238, followed by CO elimination to m/e 206-210. The group of peaks at m/e 152-154 arc the doubly charged molecular ions. An identical spectrum was obtained from an authentic standard of 2,3,7,8-tetrachlorodibenzofuran. This latter compound has a retention time identical to that of peak 4. Peak 2 is, therefore, a positional isomer. The accurate mass measurements for the characteristic ions are within 2 p.p.m. ofthe calculated exact masses. Peaks identified on this chromato gram and their retention limes relative todieldrin areas follows: h mixture of tetra- and pentachlorobiphcnyl (1.02); tctrachloro- dibetwofuran (1.30); pentachlorobiphcnyl (1.46); tctrachlorodi- bcnzoi'tirim (1.57); licxachloronaphthulenc (1.75); penta chlorobiphcnyl (I.B6); hcxachloronaphthalenc (2.00); and hi-ptachloronaphthalcne (3.46); An aliquot of combined fractions derived from the same Aroclor 1254 was treated with diuzonicthanc to assess whether any chlorinated orlhu-hydroxy- biphcnyls (pre-furans) were present. Gas chromatographic analysis of the sample before mid after ticatmenl resulted in identical chromatograms. As large quantities of PCBs Itavc entered 1 lie global environ ment1^", it may be assumed that (lie contaminant dibenzofurans 307 also have been released in proportional amounts. Their per sistence, effects, and significance icimiin to be determined. We thank .1. A. Buikc, M. L. Porter and J. Ci. Vo, for discussions; A. S. Kende for standards of chlorinated di benzofurans; and F. C. Walls for assistance with the mass spectrometry.^ This work' was supported by the Canadian Wildlife Service, National Science Foundation, and NASA. Gl KALO W. JloWtS* Canadian Wildlife Service, Michai.i. J. Mut.vittti.v. . Toxic Chemicals Section, Ottawa, Canada KiA OH3 BCRNO R. T. St.MO.VlM Space Sciences Laboratory, University of California, A. L. Burlingame Berkeley, California 94720 Bodega Marine Laboratory, U, W, Risfbkougii ' University of California, Bodega Bay, California 94923 Retttwed February 15; (mined May 28.197J, addrm; California Winf Rciou/ct! Control Board, nivilion of Flanuina ami Rnaarch, 1416 Ninth Sut. Satranwnio. California >5114. ' Newton, l,, and Bo(tn, J,, Xoture. 14*. 212-51) (1974). * Kotman. t. H,, Haddetinth, R. H., and Rijk.cld, M. F. 1. J.; Blot. C'omrrr., 4. 575-377(1972). . 7 Oilbeflion. M,, and Hair, R.. Can. nt Sot.. II, 534-JJ6(I74). llicclnbolhani. O. R.. et a/.. Solute. 270, 702-70) (1961). > Sparaetiu, G. L., Dunn. F. L., and Roar. V. X., FU Cumin. Toxi'e., 9, 40' 412 (1971). * Voa, J. a.. Kortnin J. It,. Van dtr Maai. )t. L.. ttn Noevrr dr Biauw. M. C... and da Voi, R. H, fvoS Cornier. Tusk.. I. 62S-655 (1970), l Vo, J. G.. Binron. tilth Penp., I, IOS-117 (1972). Row-ca, G. W.. Simoitali, B. R,, Burlinfamr. A. L,, dr l urpr, B. W., amt Riic- tnmjlli, R. W,, 6ti.lton. Htlh rertp.. i. 191-191(1971). Bauthman, R.and Mculum, M., /.nWton. tilth retie.,i. 27-53 (197?). Bauihman. R..and Mcarlaen. M., Atlr, Chtm.. 120, 92-104 (1975). Rtooit on 2.4,5-T(ritrcu;i' Office of \ht ?riWertt, Science Ad vUoiy Commiiiee, Utftcc of JMence tfid Technology, Mitch. 1971). Jetuen, S., tm) Renbetfi. t.. Ambfa, 1, 62-45 (19721. Firetfone, D. Rets, J.. Btown, N. L., Btrton. R. P., and Damien, J. N., J. Av.OJT. An*t}d. CW.S5, 85-92 UK2,. Porter, M. l_and Burke.J. A.J. Atf.Ot*.Atufyt. Chm., 54, 1426- 1428(1971). Bgrhnrame. A. I... OUen, R. W. and .MePhenon, R. \n Adr. Men Spear., 6, 1033-1059 (197-0. NUhci, I. C. THand Serof.m. A. F., fair**. Htlh I, 21-38 (1972). Bo*n, O. W., and Jonfccl, C. J.*/, fhh DtlCen. (in the juei*). Jettten. S.. Johnek. A. C.. OkAnn, M., and Otflind,iCr,-'Afe/*r, 224, 347- 350 (1969). Koeman, J. H.. len Nooer de Brail*, M. C.. and de Von, R. H., Salute, 221, (126 1121 (1969). Rkrbfouch, K. W.. Kekhe. P., Pcakall, D. B.. Herman, S. C.. and Kirven. M. N., Nature. 210, 1094-1)02 (1968). Niche breadth in Bryozoa . as a test of competition theory Competition theory predicts that intraspecific and inter specific competition should often have opposite effects on the use of resources by a population, the former increas ing, the latter decreasing, the range of resource actually used'''. Field data supporting these predictions are well known for the intcrspcciffc case1'* but arc scarce for the intraspecific condition, and we have been unable to find any reference demonstrating both effects within a single species. We therefore report here the verification of both predictions In respect of competition for space by the epiphytic hryozoan Alcyonidium lunutum: less extensive data suggesting the same effects within other bryozoans are also reported. ' tniraspccifie competition should result in an increase in the range of a resource spectrum used by a species, as at high population levels the advantages lo any individual of being at the competition-free optimum of a resource gradient are offset by the intense intraspecific competition found there (Fig. lu); this is the `principle of equal oppor tunity' of MacArthur'. Interspecific competition, on the other hand, should tend to restrict the range of the resource spectrum used by a species, as individuals attempting to exploit marginal resources cannot do so as efficient!) as 727351 NEV 0 1 9 2 9 6 WATER PCB-SD0000035048