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1.
The Carbon Economy of Rubus chamaemorus L. II. Respiration 总被引:1,自引:0,他引:1
Respiratory activity and seasonal changes in carbohydrate contentof the storage organs of Rubus chamaemorus L. have been investigated.Leaf dark respiration rate increases in a non-linear mannerfrom 0·7 mg CO2 evolved dm2 h1 at 0 °Cto 4·6 rng CO2 evolved dm2 hh1 at 30 °C.Root and rhizome respiration rates increase from 1 µ1O2 uptake g1 fresh weight h1 at 0.7 ° C to10 µ10, uptake g1 f. wt h1 at 20 °C.Rhizome carbohydrate reserves decline from a September peakof 33 per cent alcohol insoluble d. wt to 16 per cent in May. The circumpolar distribution of R. chamaemorus is discussedin relation to the evidence presented here and in the precedingpaper of the series. 相似文献
2.
Amounts of the enzyme ribulose-1,5-bisphosphate carboxylasewere estimated in seedling leaves of barley (Hordewn vulgareL.) and flag leaves of wheat (Triticum aestitum L.) by radialimmuno diffusion. A fourfold variation among barley varietiesfor amount of RuBPCase at the seedling stage was observed (c.3.515mg g1 fr. wt). Range in variation for amountof flag leaf RuBPCase among wheat varieties was 6-09-9.39 mgRuBPCase g1 fr. wt. F1 hybrids from interspecific andintergeneric crosses of crested wheatgrasses (Agropyron andElymus spp.) and their amphidiploid analogues were comparedfor amount of RuBPCase in the most recent fully expanded leavesharvested before seed set. Amount of enzyme varied from 3.4to 77.6 mg g1 fr. wt among the hybrids. No effect chromosomenumber on enzyme concentration was observed among 13 hybridsand their amphidiploid counterparts. Key words: RuBPCase, wheatgrasses 相似文献
3.
Carbon dioxide efflux from 5- to 20-day-old pea fruits was measuredfor plants grown in controlled environment at 15 °C and600 µmol s1 m2 photon flux density in a16 h photoperiod. The rate of CO2 output per fruit increasedquickly from 0.005 to 0.018 mg CO2 min1 during fruitelongation and subsequently more slowly to 0.030 mg CO2 min1as the fruits inflated. On a d. wt basis the rate was highest,0.175 mg CO2 g1 min1, in the youngest fruits anddeclined curvilinearly with increasing fruit weight to 0.02mg CO2 g1 min1. Separation of maintenance andgrowth components was achieved by starvation methods and bymultiple regression analysis. From the latter method estimatesof the maintenance coefficient declined hyperbolically from150±8.7 mg carbohydrate g1 d. wt day1 inthe very young fruits (0.05 g) to 10.4±0.36 mg carbohydrateg1 d. wt day1 in older fruits (2.0 g). On a nitrogenbasis maintenance costs decreased from 2240 to 310 mg carbohydrateg1 nitrogen day1 while nitrogen concentrationfell from 6.7 to 3 per cent d. wt. A simple linear relationshipbetween maintenance cost per unit d. wt and nitrogen concentrationwas not observed. A growth coefficient of 50±6.7 mg carbohydrate g1growth (equivalent to a conversion efficiency, YG, of 0.95)was estimated for all fruits examined. The overall efficiency, Y, increased from a mean of 0.70 to0.85 during fruit elongation and subsequently declined to 0.80.For a given fruit weight, efficiency increased asymptoticallywith relative growth rate; both asymptote and slope of the relationshipincreased as the fruits grew. Pisum sativum L., garden pea, legume fruit, carbon dioxide efflux, maintenance respiration, growth respiration 相似文献
4.
During the ripening stage of barley and rice, the sink activitywas defined as the dry matter increase per units sink size,leaf area and time, as follows: NAR = A.SinkW+NAR', where NAR is the net assimilation rate (g d.wt dm2d1);A is the sink activity [g d.wt g1d.wt (ear) dm2d1]; Sink W is ear wt per plant at heading (g d.wt);and NAR' is net assimilation rate excluding the assimilate ofsink organ (g d.wt dm2 d1). Plant material with 16 combinations of mutually different sink(ear) and source (leaf) size were produced at heading for eachcrop: parts of each leaf and ear were removed to produce fourgrades in barley, and also a part of each leaf was removed producingfour grades for four rice varieties showing different ear size.NAR and NAR' were determined during 26 and 21 d in barley andrice after heading, respectively. Sink activity (A), representedas the assimilation rate induced by the sink organ, was estimatedfrom the relationship between SinkW and NAR using the previousequation. The sink activity was significantly higher in ricewith a value of 00.028 g d.wt g1 d.wt (ear) dm2d1 vs. 00.0017 in barley, suggesting that therelative role of leaves for grain filling is considerably higherin rice than in barley. The sink activity obtained in the studymight be introduced into a model to predict the yields of barleyand rice. Hordeum vulgare L, barley, Oryza saliva L, rice, dry matter, NAR, sink, source, sink activity, model 相似文献
5.
The Translocation of 3,5-Dichlorophenoxyacetic Acid in Relation to its Effect on Potato Common Scab 总被引:1,自引:0,他引:1
The translocation of 3,5-dichlorophenoxyacetic acid (3,5-D)in the potato plant was studied to clarify the mode of actionagainst potato common scab. 3,5-D was translocated to the tuberfaster and metabolised less than 2,4-D. Translocation to tuberswas proportional to growth and a concentration of 1025nmol 3,5-D g1 fr. wt was attained 8 d after a foliarapplication. Previous evidence indicates this concentrationwas insufficient to be directly toxic to the pathogen Streptomycesscabies and the results suggest that 3,5-D acts in the tuberby altering the host's response to infection. 相似文献
6.
The calanoid copepod, Eudiaplomus graciloides, was reared fromegg to adult on uni-algal diets (0.1. 0.5 and 2.5 mg dry wt11) using the green alga, Chlamydomonas reinhardtii,as food, or on a mixed diet consisting of Lake Esrom water filteredthrough a plankton net with pore size 45 µm and supplementedwith C. reinhardtii (2.5 mg dry wt 11). On the mixeddiet at 21.0°C growth in body dry wt (W, µg dry wt)was exponential, and the growth constants were 0.21 day1in the early to mid juvenile stage (N1 - C4) and 0.11 day1in the late juvenile to early adult stage (C4-A). At 14.5°Cthe corresponding growth rate constants were 0.10 and 0.08 day1.Similar growth rates were found at uni-algal concentrationsof 0.5 and 2.5 mg dry wt I1, and it was argued that thethreshold concentration for growth in Eudiaptomus was closeto 0.1 mg dry wt I1. The clearance (C, ml h1)of copepodites was measured on the uni-algal diets. The constantsof the regression (C = aWb) were: a = 0.125, b = 0.858 (2000C. reinhardtii ml1), a = 0.068, b = 0.849 (10 000), a= 0.028, b = 0.875 (50 000). Ingestion rates were calculatedfrom the clearances and the average algal concentrations. Atthe three food levels the average daily rations were 30, 67and 125% of body dry wt. The respiration rate (R, nl O2 h1)was measured in individuals reared on the mixed diet. The constantsof the regression (R = aWb) were: a = 4.82, b = 1.07 (nauplii,14.5°C), a = 4.17, b = 0.904 (copepodites and adults, 14.5°C),a = 6.87, b = 0.757 (copepodites and adults, 21.0°C). Nosignificant difference in the respiration rate of copepoditesreared on uni-algal diets and the mixed diet could be demonstrated.Energy budgets were calculated. The assimilation efficiencyand the gross growth efficiency of copepodites decreased markedlywith increasing food concentration, the net growth efficiencyvaried from an average of 0.44 at the lowest algal concentrationto 0.60 on the mixed diet. The results are discussed in relationto previous findings with both freshwater and marine copepods. 相似文献
7.
The Growth Rate of Wheat Leaves in Relation to the Extension Zone Sugar Concentration Manipulated by Shading 总被引:1,自引:0,他引:1
The main objective of this study was to determine the relationshipbetween the relative rate of growth of emerging wheat leavesand the hexose sugar concentration of the extension zone. Shortperiods of intense shading (to 20 or 5% of full sun for up to14 d) were used to decrease hexose concentrations. Shading decreased hexose concentrations to a fraction of thatof controls and also resulted in thin and narrow leaves thatwere less in dry weight than control leaves of the same length.Shading did however increase the length of the zone of extendingtissue at the leaf base by 30%. The effect of hexose concentrations on the relative rate ofleaf growth was evaluated by determining the ratio between growthrates of shaded and control leaves. This ratio declined as hexoseconcentrations declined and the relationship was described bya rectangular hyperbola (r > 0.95, P < 0.01). Combineddata from many leaves on the main shoot and its tillers fromtwo irrigated wheat crops all conformed to the same relationship.The hexose concentrations where the ratio of growth rates washalf the maximum rate were 0.42 mg g1 fr. wt. for extensiongrowth and 1.74 mg g1 fr. wt. for dry weight growth.These values were significantly (P < 0.01) different. These results were compared with data from emerging leaves offield crops and it was concluded that hexose concentrationshad not limited leaf growth rates, the lowest values recordedbeing 2.53.0 mg g1 fr. wt. It was further suggestedas unlikely that leaf growth rates of wheat crops in the fieldwould be limited by hexose concentrations. 相似文献
8.
The growth rate of a population of Euphausia lucens from thewest coast of South Africa was estimated from laboratory studiesand from monthly size-frequency distributions of samples collectedover a 1-year period. Laboratory studies indicated that growthrates ranged from 0.131 (larvae) to 0.047 mm day1 (juveniles),while size-frequency distributions suggested a growth rate of{small tilde}0.026 mm day1 for the adults. The mean annualbiomass from the inshore, intermediate and offshore regionsranged from 9.75 to 47.29 mg dry wt m3 with the highestbiomass being found in the inshore region. Calyptopis larvaewere present for most months of the year, indicating continuousrecrwtment. The relative contribution of flesh, moults and eggsto the total annual production was estimated separately forall three regions. Production due to growth (Pg) was estimatedto be 92.71185.60 mg dry wt m3 year1, whileexuviai production (Pe) varied between 60.01 and 281.38 mg drywt m year Production of eggs (Pr) was estimated to range from5.07 to 12.39 mg dry wt m year the lowest value being obtainedin the inshore region. Moult production represented {small tilde}6times the mean biomass in each region, while the P/B ratio forflesh production varied from 3.92 to 8.91, the highest ratiobeing obtained in the offshore region. Total P/B ratios rangedfrom 10.14 to 16.01. 相似文献
9.
Limiting effect of abioseston on food ingestion, postembryonic development time and fecundity of daphnids in Lake Balaton (Hungary) 总被引:2,自引:0,他引:2
During ice-free periods, seston ranges from 10 to 600 and averages29.2 mg dry wt 11 in Lake Balaton, the largest shallowlake in Central Europe. Most (8099%) of the seston consistsof 110 µm sized mineral particles. The abiosestoncauses permanent food limitation in the ingestion of the ediblephytoplankton (122 µm fraction) by Daphnia cucullataand D.galeata. The postembryonic development time of D.galeataincreases and its fecundity decreases with increasing abioseston.The fecundity and the mortality of D.galeata are balanced atan abioseston concentration of 20.0 mg dry wt 11. 相似文献
10.
Soya Bean Seed Growth and Maturation In vitro without Pods 总被引:2,自引:0,他引:2
OBENDORF R. L.; TIMPO E. E.; BYRNE M. C.; TOAI T. V.; RYTKO G. T.; HSU F. C.; ANDERSON B. G. 《Annals of botany》1984,53(6):853-863
Immature Glycine max (L.) Merrill seeds, initially between 50and 450 mg f. wt, were grown and matured successfully in vitro.Excised seeds were floated in a liquid medium containing 5 percent sucrose, minerals and glutamine in flasks incubated at25 °C under 300 to 350 µE m2 s1 fluorescentlight. During 16 to 21 d in culture, seeds grew to a matured. wt of 100 to 600 mg per seed at an average rate of 5 to 25mg d. wt per seed d1 depending on initial size. Growthrates were maximal during the first 8 to 10 d in vitro but declinedwith loss of green colour in the cotyledons. Seed coats rupturedwith rapid cotyledon expansion during the first 2 d in culture.Embryos were tolerant to desiccation and 80 to 90 per cent germinatedif removed from culture before complete loss of green colour.The growth of excised seeds in vitro exceeded the growth ofseeds in detached pods, but when windows were cut in pods topermit direct exposure of seeds to the medium, seed growth wascomparable. Glycine max (L.) Merrill, soya bean, seed culture, seed growth, seed maturation, germination 相似文献
11.
The present study deals with structure and functioning of threeareas of Himalayan oak forest. Low- and mid-altitude oaks, namelyQuercus leucotrichophora, and Quercus floribunda, form predominantevergreen forests in Central and Western Himalaya. The totaltree basal cover ranged between 33·89 m2 ha1 (Q.floribunda site) to 36·83 m2 ha1 (Q. leucotrichophorasite). The density ranged between 570 and 760 individuals ha1.Allometric equations relating biomass of different tree componentsto GBH (girth at breast height) were significant with the exceptionof leaf biomass in Q. leucotrichophora and Rhododendron arboreum.Total vegetation biomass (29·40467·0 tha1) was distributed as 377·1 t ha1 intrees, 5·40 t ha1 in shrubs and 1·23 tha1 in herbs. Total forest floor biomass ranged between4·6 and 6·2 t ha1. Of the total annuallitter fall (4·74·8 t ha1), 77·5% was contributed by leaf litter, 17·8 % by wood litterand 4·7 % by miscellaneous litter. Turnover rate of treelitter varied from 0·66 to 0·70. Net primary productionof total vegetation ranged between 15·9 and 20·6t ha1 yr1, of which the contribution of trees,shrubs and herbs was 81·2 %, 8·6 % and 10·2%, respectively. A compartment model of dry matter on the basisof mean data across sites was developed to show dry matter storageand flow of dry matter within the system. Quercus leucotrichophora forest, Q. floribunda forest, Q. lanuginosa forest, biomass, litter fall, net primary production, compartmental transfer 相似文献
12.
Stem from three- and four-week-old Soyabean [Glycine max (L.)Merr. cv. Tracy] plants reduced from 0.3 to 0.7 µmol nitratehl gl f. wt. Leaf activity was 4.77.6 µmolnitrate hl gl f. wt. Outer stem was two to fourtimes more active at reducing nitrate than was inner stem. Plantnitrate nutrition had a strong effect upon the ratio of activitypresent in stem and leaf. More nitrate increased the proportionpresent in leaves. Glycine max L., soyabean, nitrate assimilation, nitrogen metabolism, Rhizobium japonicum 相似文献
13.
TAYLOR JOHN S.; BLACKMAN SUSAN J.; YEUNG EDWAERD C. 《Journal of experimental botany》1982,33(3):495-505
Endogenous cytokinin and gibberellin-like activity were measuredby bioassay in developing fruit of the orchid Epidendrum ibaguense.Cytokinins decline during the first 30 d after pollination,then begin to accumulate, with very high levels (113µ g zeatin eq. g1 dry wt. ) in the mature fruitand seed. The major structural change in developing fruit duringthe first 30 d is the ongoing cell division in the fruit wall.By day 30 most ovules have been fertilized and embryo developmentbegins. The increase in cytokinin activity thus coincides withthe onset of embryo development. Gibberellin levels declinein the fruit throughout development, although high activity(0.9 µ g GA3 eq. g1 dry wt. ) is observed in themature seed. The mature embryo shows no obvious structural differentiationinto embryonic axis and cotyledon and no endosperm develops. 相似文献
14.
Summer coastal zooplankton biomass and copepod community structure near the Italian Terra Nova Base (Terra Nova Bay, Ross Sea, Antarctica) 总被引:7,自引:0,他引:7
Pane Luigi; Feletti Mirvana; Francomacaro Barbara; Mariottini Gian Luigi 《Journal of plankton research》2004,26(12):1479-1488
The structure of the zooplankton biotic community and of copepodpopulation in the coastal area of Terra Nova Bay (Ross Sea,Antarctica) was investigated during the 10th Italian AntarcticExpedition (1994/1995). Zooplankton biotic community consistedmainly of pteropods (Limacina helicina and Clione antarctica),Cyclopoid (Oithona similis), Poecilostomatoid (Oncaea curvata)and Calanoid (Ctenocalanus vanus, Paraeuchaeta antarctica, Metridiagerlachei and Stephos longipes) copepods, ostracods, larvalpolychaetes and larval euphausiids. Zooplankton abundance rangedfrom 48.1 ind m3 to 5968.9 ind m3, and copepodabundance ranged from 45.2 ind m3 to 3965.3 ind m3.The highest peak of zooplankton abundance was observed between25 m and the surface and was mainly due to the contributionof O. similis, O. curvata and C. vanus. Zooplankton biomassranged from 5.28 mg m3 to 13.04 mg m3 dry weight;the maximum value was observed between 25 m and the surface.Total lipid content varied from 216.44 to 460.73 mg g1dry weight. 相似文献
15.
Nitrate Effects on Pre-emergence Growth and Emergence Percentage of Wheat (Triticum aestivum L.) from Different Sowing Depths 总被引:1,自引:0,他引:1
The effects of a range of applied nitrate (NO3) concentrations(020 mol m3) on germination and emergence percentageof Triticum aestivum L. cv. Otane were examined at 30, 60, 90and 120 mm sowing depths. Germination percentage was not affectedby either sowing depth or applied NO3 concentration whereasemergence percentage decreased with increased sowing depth regardlessof applied NO3 concentration. Nitrate did not affectemergence percentage at 30 mm sowing depth, but at 60 to 120mm depth, emergence percentage decreased sharply with an increasedapplied NO3 concentration of 0 to 1·0 mol m3then decreased only slightly with further increases in appliedNO3 of about 5·0 mol m3. Root and shoot growth, NO3 accumulation and nitrate reductaseactivity (NRA) of plants supplied with 0, 1·0 and 1·0mol m3 NO3 at a sowing depth of 60 mm were measuredprior to emergence. The coleoptile of all seedlings opened withinthe substrate. Prior to emergence from the substrate, shootextension growth was unaffected by additional NO3 butshoot fr. wt. and dry wt. were both greater at 1·0 and1·0 mol m3 NO3 than with zero NO3.Root dry wt. was unaffected by NO3. Nitrate concentrationand NRA in root and shoot were always low without NO3.At 1·0 and 10 mol m3 NO3, NO3 accumulatedin the root and shoot to concentrations substantially greaterthan that applied and caused the induction of NRA. Regardlessof the applied NO3 concentration, seedlings which failedto emerge still had substantial seed reserves one month afterplanting. Coleoptile length was substantially less for seedlingswhich did not emerge than for seedlings which emerged, but wasnot affected by NO3. It is proposed that (a) decreasedemergence percentage with increased sowing depth was due tothe emergence of leaf I from the coleoptile within the substrateand (b) decreased emergence percentage with additional NO3was due to the increased expansion of leaf 1 within the substrateresulting in greater folding and damage of the leaf. Key words: Triticum aestivwn L., nitrate, sowing depth, seedling growth, seedling emergence 相似文献
16.
The specific respiration rates of nodulated root systems, ofnodules and of roots were determined during active nitrogenfixation in soya bean, navy bean, pea, lucerne, red clover andwhite clover, by measurements on whole plants before and afterthe removal of nodule populations. Similar measurements weremade on comparable populations of the six legumes, lacking nodulesbut receiving abundant nitrate-nitrogen, to determine the specificrespiration of their roots. All plants were grown in a controlled-environmentclimate which fostered rapid growth. The specific respiration rates of nodulated root systems ofthe three grain and three forage legumes during a 714-dayperiod of vegetative growth varied between 10 and 17 mg CO2g1 (dry weight) h1. This mean value consistedof two components: a specific root respiration rate of 69mg CO2 g1 h1 and a specific nodule respirationrate of 2246 mg CO2 g1 h1. Nodule respirationaccounted for 4270 per cent of nodulated root respiration;nodule weight accounted for 1240 per cent of nodulatedroot weight. The specific respiration rates of roots lackingnodules and utilizing nitrate nitrogen were generally 2030per cent greater than the equivalent rates of roots from nodulatedplants. The measured respiratory effluxes are discussed in thecontext of nitrogen nitrogen fixation, nitrate assimilation. Glycine max, Phaseolus vulgaris, Pisum sativum, Medicago sativa, Trifolium pratense, Trifolium repens, soya bean, navy bean, pea, lucerne, red clover, white clover, nodule respiration, root respiration, fixation, nitrate assimilation 相似文献
17.
The number, size (mm3 pellet 1) and total volume of fecalpellets produced (mm3 h1) by Boeckella titicacae increasedwith concentration of Chlorella and natural seston in threedifferent lakewaters from Bahia de Puno and Lago Grande of LakeTiticaca and nearby Laguna Arapa. The three lakewaters differedin the size and number of fecal pellets produced at seston concentrations>0.5 mg dry wt l1. However, the total volume of fecalpellets egested varied little. Large-sized food (>10 µg)resulted in larger pellets but smaller total fecal production.Food concentration had parallel effects on the production offeces and on feeding rates. Both fecal production and feedingincreased linearly with food concentration with saturation between5 and 7.5 x 105 Chlorella ml1 (3.75.6 mg dry wtl1). Varied responses in fecal production when fed differentsize fractions of lake seston suggest Boeckella has a complexand flexible feeding behavior. Feeding preferences of B.titicacaeand B.occidentalis (Ivlev index) for two seston size fractionsare generally reflected by fecal production. 相似文献
18.
Fully light-intercepting simulated swards of S24 perennial ryegrasswere exposed to contrasting environmental conditions in a growthroom for 4 days. Half experienced 20 h days of 120 Wm2(400700. nm) and 5 °C, and came to have a WSC (watersoluble carbohydrate) content of 235 mg g1 and half 4h days of 20 Wm2 and 25 °C leading to a WSC of 25mg g1. Their rates of CO2 efflux were monitored at anumber of temperatures during an 8 h dark period; half experiencedincreasing (530 °C) and half decreasing (305°C) temperatures. The high WSC swards hadrespiration rates of 3.7 mg CO2 g1 (d. wt) h1at 15 °C, and the low swards 0.8 mg CO2 g1h1. The order in which the temperatures were experiencedwas immaterial. Even the low WSC swards showedno evidence of a respiratory decline during the dark periodthat could be attributed to substrate shortage. The relationshipbetween temperature and CO2 efflux was best represented by logisticcurves. Even so, a Q10 of 2 fitted the data reasonably well,at least up to 20 °C, and has practical advantages wheninterpolating estimated between measured values of respirationin the construction of a carbon balance sheet. Lohum perenne L., ryegrass, respiration, temperature, Q10, soluble carbohydrate content, simulated sward 相似文献
19.
In Lupinus albifrons flowers the banner spot of the standardis initially coloured white or pale yellow. Two to three daysafter reaching the stage of full flower opening, this bannerspot develops a pinkish blush and is deep magenta after a further24 h. The development of this pigmentation is accelerated byexposure to ethylene in a concentration- and time-dependentmanner. Flowers with a pinkish banner spot produced the greatestamounts of ethylene and production was much lower in flowerswhich had either completed the colour change or in which thebanner spot colour remained unchanged. Treatments such as stigmaremoval or pollination increased the rate of ethylene production.Dissection of the flowers showed that while the banner spotis changing colour there is no change in the rate of productionof ethylene from the standard, i.e. from the banner spot orsurrounding tissue. The major sites of production at this timeare the keel and pistil. Isolated flowers withered within 2 d of removal from the plantand therefore did not show any change in the colour of the bannerspot unless exposed to ethylene. The increase in banner spotpigment was about fourfold when isolated floweres were exposedto ethylene (0·24 µl 11): however, the increasewas less than twofold when isolated standards were exposed toethylene (0·27 µl I1). Application of silverthiosulphate (STS) to intact isolated flowers, as a 1 h pulseprior to ethylene exposure, partially prevented the pigmentaccumulation, whilst a continuous supply of STS reduced theethylene-induced colour change by approx. 50% Low concentrationsof cycloheximide (CHI) (0·01 mg ml1) reduced theaccumulation of pigment in the banner spot of ethylene-treatedflowers, and higher concentrations (1·0 mg ml1)completely prevented the ethylene-induced colour change. Ethylene, flower senescence, Lupinus albifrons, pollination 相似文献
20.
Population structure and production of Eudiaptomus gracilis(G.O. Sars) have been calculated from daily measurements inLake Balaton for one month during each summer in 1975 and 1977.Fecundity was different in the two years 6.98 ? 1.16 and 10.68? 1.42 in 1975 and 1977, respectively. A total of 80% and 64%of the population were made up of larvae in 1975 and 1977, respectively.The ratio of males to females was 1:1.63 and 1:1.1, respectively.In 1975 it was possible to follow the development of cohorts,19 20 days in the former year, 17 20 days in thelatter. In both years of examination 80 83% of naupliiand 1215% of copepodites were eliminated. Daily net biomassproduction was 6.88 mg (dry wt.)/m3 in 1975 and 1.94 mg (drywt.)/m3 in 1977. Ratios of eggs, nauplii and copepodites indaily production was 1:2.4:1.4 in 1975 and 1:1.0:1.0 in 1977.The daily potential biomass production were 34.40 mg (dry wt.)/m3 and 10.28 mg (dry wt.)/m3 and the elimination were 80 and81 wt.%, respectively. P/B ratio allowing for net productionvalues was nearly the same in both periods of investigation(0.12 and 0.099 respectively). 相似文献