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1.
To estimate the age and growth of dominant lanternfishes in the Kuroshio–Oyashio Transition Zone, we examined the sagittal
otolith microstructure of Symbolophorus californiensis (n = 30) and Ceratoscopelus warmingii (n = 93) collected from the western North Pacific during 1997–2003. Age of S. californiensis ranged from 81 to 541 days corresponding to postmetamorphosis stage (juveniles and adults), and the von Bertalanffy model
was fitted: L
t
= 128[1 − exp{−0.003(t − 1.52)}], where L is the standard length (mm) and t is age in days. Age of C. warmingii ranged from 6 to 416 days, and growth before metamorphosis was linear (L
t
= 0.346t + 1.51), and the von Bertalanffy model was fitted to the postmetamorphosis stage: L
t
= 80.8 [1 − exp{−0.00769(t − 34.4)}]. Growth of these two lanternfishes was faster than that of other lanternfishes in previous studies but considerably
slower than that of Japanese sardine (Sardinops melanostictus) and anchovy (Engraulis japonicus) distributed in the Kuroshio–Oyashio Transition Zone. Temperature and prey availability are discussed in relation to this
difference in growth rate. 相似文献
2.
To ascertain the feeding habits of benthic juvenile yellowfin goby Acanthogobius flavimanus, the gut contents of 599 specimens (15–41 mm in standard length, SL), collected on a tidal mudflat in the Tama River estuary
throughout the diel cycle, were examined. The major prey items changed from harpacticoid copepods to errant and sedentary
polychaetes at ca. 20 mm SL. Prey width increased with fish size. Fish of 26–28 mm SL fed mainly from sunset to morning, with
highest feeding intensity during twilight hours and/or high tide. Based on the gut evacuation rate estimated from a forced
feeding experiment in the laboratory and data for the diel change of mean gut-content volume in the field, the daily ration
of juvenile yellowfin goby (26–28 mm SL) was calculated to be 13.8 mm3 fish−1 day−1. This volume is approximately equivalent to 3.9 individuals of the errant polychaete Ceratonereis erythraeensis (9.7 mm in body length, BL) or 8.1 individuals of the sedentary polychaete Prionospio japonica (14.8 mm BL), both species occurring abundantly on the mudflat during the study. 相似文献
3.
Age and growth of Lestrolepis japonica (Aulopiformes: Paralepididae) in Kagoshima Bay,southern Japan
Age and growth of a paralepidid, Lestrolepis japonica, were determined from sagittal otoliths of specimens collected from April 2001 to February 2002 in Kagoshima Bay, southern
Japan. Marginal growth increments indicated that the annulus was formed once a year, in August and September. Four groups
were recognized, having none, one, two, or three annuli, respectively. Age in months was assigned to each individual on the
basis of August as the birth month. The maximum recorded age was 48 months. Growth was expressed by von Bertalanffy's equation,
L
t
= 171.91{1 − exp[−0.148(t + 0.403)]}, t being the age in months and L
t
the standard length (mm) at age t.
Received: July 15, 2002 / Revised: November 18, 2002 / Accepted: December 10, 2002 相似文献
4.
Nelusetta ayraudi (the ocean leatherjacket) is an endemic Australian monacanthid species distributed from North West Cape (Western Australia)
south to southern Queensland. The commercial and recreational fisheries targeting Nelusetta ayraudi have expanded substantially along the coast of New South Wales (NSW) in recent years but there exists little biological information
on which to base effective management of this growing fishery. World-wide, only a few studies have aged monacanthids. Of these,
researchers have interpreted periodic increments in bony structures such as vertebrae and anterior dorsal spines in preference
to those found in otoliths. In this study we estimated age of N. ayraudi by counting growth increments in sectioned otoliths. The periodicity of increment formation was validated using a vital stain,
(oxy-tetracycline), injected into young-of-the-year fish. Growth was rapid especially as juveniles with N. ayraudi attaining approximately 220 mm after 1 year and 340 mm after 2 years. No differences in growth rates were detected between
sexes or between fish captured at different latitudes (zones). The largest male (605 mm, Total Length—TL) and female (656 mm,
TL) were both recorded from northern NSW, with both sexes attaining the maximum age of 6+ years from northern and southern
NSW. The von Bertalanffy parameters describing growth for N. ayraudi were L¥ {L_\infty } = 591 mm (TL), k = 0.377 year−1 and t
o = −0.247 years. 相似文献
5.
Booth DT Thompson MB Herring S 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2000,170(4):269-276
Eggs of two small Australian lizards, Lampropholis guichenoti and Bassiana duperreyi, were incubated to hatching at 25 °C and 30 °C. Incubation periods were significantly longer at 25 °C in both species, and
temperature had a greater effect on the incubation period of B. duperreyi (41.0 days at 25 °C; 23.1 days at 30 °C) than L. guichenoti (40.1 days at 25 °C; 27.7 days at 30 °C). Patterns of oxygen consumption were similar in both species at both temperatures,
being sigmoidal in shape with a fall in the rate of oxygen consumption just prior to hatching. The higher incubation temperature
resulted in higher peak and higher pre-hatch rates of oxygen consumption in both species. Total amount of oxygen consumed
during incubation was independent of temperature in B. duperreyi, in which approximately 50 ml oxygen was consumed at both temperatures, but eggs of L. guichenoti incubated at 30 °C consumed significantly more (32.6 ml) than eggs incubated at 25 °C (28.5 ml). Hatchling mass was unaffected
by either incubation temperature or the amount of water absorbed by eggs during incubation in both species. The energetic
production cost of hatchling B. duperreyi (3.52 kJ · g−1) was independent of incubation temperature, whereas in L. guichenoti the production cost was greater at 30 °C (4.00 kJ · g−1) than at 25 °C (3.47 kJ · g−1). Snout-vent lengths and mass of hatchlings were unaffected by incubation temperature in both species, but hatchling B. duperreyi incubated at 30 °C had longer tails (29.3 mm) than those from eggs incubated at 25 °C (26.2 mm). These results indicate that
incubation temperature can affect the quality of hatchling lizards in terms of embryonic energy consumption and hatchling
morphology.
Accepted: 27 January 2000 相似文献
6.
A. Q. Hurtado A. T. Critchley A. Trespoey G. Bleicher-Lhonneur 《Journal of applied phycology》2008,20(5):551-555
Kappaphycus striatum var. sacol was grown in two separate studies: (1) at two stocking densities, and (2) at four different depths, each for three different
durations of culture (30, 45 and 60 days) in order to determine the growth rate of the seaweed and evaluate the carrageenan
content and its molecular weight. The results demonstrated that stocking density, duration of culture and depth significantly
(P < 0.01) affected the growth rate, carrageenan content and molecular weight of K. striatum var. sacol. Decreasing growth rate was observed at both stocking densities and at four depths as duration of culture increased. A lower
stocking density (500 g m−1line−1) showed a higher growth rate for the shortest durations, i.e. 30 days, as compared to those grown at a higher density. Likewise,
decreasing growth rate was observed as depth increased, except at 50 cm after 60 days of culture. A 45-day culture period
produced the highest molecular weight at both stocking densities (500 g m−1line−1 = 1,079.5 ± 31.8 kDa, 1,000 g m−1line−1 = 1,167 ± 270.6 kDa). ‘Sacol’ grown for 30 days at 50 cm (1,178 kDa) to 100 cm (1,200 kDa) depth showed the highest values
of molecular weight of carrageenan extracted. The results suggested that K. striatum var. sacol is best grown at a stocking density of 500 g m−1line−1, at a depth of 50–100 cm, and for a duration of 30 days in order to provide the highest growth rate, carrageenan content
and molecular weight. 相似文献
7.
J. Carlos Roseiro P. J. Partidário N. Lobo M. J. Marçal 《Applied microbiology and biotechnology》1999,52(4):546-552
The change of dilution rate (D) on both Methylophilus methylotrophus NCIMB11348 and Methylobacterium sp. RXM CCMI908 growing in trimethylamine (TMA) chemostat cultures was studied in order to assess their ability to remove
odours in fish processing plants. M. methylotrophus NCIMB11348 was grown at dilution rates of 0.012–0.084 h−1 and the biomass level slightly increased up to values of D around 0.07 h−1. The maximum cell production rate was obtained at 0.07 h−1 corresponding to a maximum conversion of carbon into cell mass (35%). The highest rate of TMA consumption was 3.04 mM h−1 occurring at D=0.076 h−1. Methylobacterium sp. RXM CCMI908 was grown under similar conditions. The biomass increased in a more steep manner up to values of D around 0.06 h−1. The maximum cell production rate (0.058 g l−1h−1) was obtained in the region close to 0.06 h−1 where a maximum conversion of the carbon into cell mass (40%) was observed. The maximum TMA consumption was 2.33 mM h−1 at D=0.075 h−1. The flux of carbon from TMA towards cell synthesis and carbon dioxide in both strains indicates that the cell is not excreting
products but directing most of the carbon source to growth. Carbon recovery levels of approximately 100% show that the cultures
are carbon-limited. Values for theoretical maximum yields and maintenance coefficients are presented along with a kinetic
assessment based on the determination of the substrate saturation constant and maximum growth rate for each organism.
Received: 25 February 1999 / Received revision: 14 May 1999 / Accepted: 17 May 1999 相似文献
8.
Mineralization of pentachlorophenol in a contaminated soil by Pseudomonas sp UG30 cells encapsulated in κ-carrageenan 总被引:2,自引:0,他引:2
M B Cassidy H Mullineers H Lee J T Trevors 《Journal of industrial microbiology & biotechnology》1997,18(1):43-48
A fermentation process in Escherichia coli for production of supercoiled plasmid DNA for use as a DNA vaccine was developed using an automated feed-back control nutrient
feeding strategy based on dissolved oxygen (DO) and pH. The process was further automated through a computer-aided data
processing system to regulate the cell growth rate by controlling interactively both the nutrient feed rate and agitation
speed based on DO. The process increased the total yield of the plasmid DNA by approximately 10-fold as compared to a manual
fed-batch culture. The final cell yield from the automated process reached 60 g L−1 of dry cell weight (OD600 = 120) within 24 h. A plasmid DNA yield of 100 mg L−1 (1.7 mg g−1 cell weight) was achieved by using an alkaline cell lysis method. Plasmid yield was confirmed using High Performance Liquid
Chromatography (HPLC) analysis. Because cells had been grown under carbon-limiting conditions in the automated process,
acetic acid production was minimal (below 0.01 g L−1) throughout the fed-batch stage. In contrast, in the manual process, an acid accumulation rate as high as 0.36 g L−1 was observed, presumably due to the high nutrient feed rates used to maintain a maximum growth rate. The manual fed-batch
process produced a low cell density averaging 10–12 g L−1 (OD600 = 25–30) and plasmid yields of 5–8 mg L−1 (approximately 0.7 mg g−1 cells). The improved plasmid DNA yields in the DO- and pH-based feed-back controlled process were assumed to be a result
of a combination of increased cell density, reduced growth rate (μ) from 0.69 h−1 to 0.13 h−1 and the carbon/nitrogen limitation in the fed-batch stage. The DO- and pH-based feed-back control, fed-batch process has
proven itself to be advantageous in regulating cell growth rate to achieve both high cell density and plasmid yield without
having to use pure oxygen. The process was reproducible in triplicate fermentations at both 7-L and 80-L scales.
Received 22 March 1996/ Accepted in revised form 20 September 1996 相似文献
9.
Codium fragile (Suringar) Hariot is an edible green alga farmed in Korea using seed stock produced from regeneration of isolated utricles
and medullary filaments. Experiments were conducted to reveal the optimal conditions for nursery culture and out-growing of
C. fragile. Sampling and measurement of underwater irradiance were carried out at farms cultivating C. fragile at Wando, on the southwestern coast of Korea, from October 2004 to August 2005. Growth of erect thalli and underwater irradiance
were measured over a range of depths for three culture stages. During the nursery cultivation stage (Stage I), growth rate
was greatest at 0.5 m depth (0.055 ± 0.032 mm day−1), where the average midday irradiance over 60 days was 924 ± 32 μmol photons m−2 s−1. During the pre-main cultivation stage (Stage II), the greatest growth rate occurred at a depth of 2 m (0.113 ± 0.003 mm day−1) with an average irradiance of 248 ± 116 μmol photons m−2 s−1. For the main cultivation stage (Stage III) of the alga, thalli achieved the greatest increase in biomass at 1 m depth (7.2 ± 1.0 kg
fresh wt m−1). These results suggest that optimal growth at each cultivation stages of C. fragile could be controlled by depth of cultivation rope. 相似文献
10.
Felipe Amezcua Ivan Martínez-Tovar Yanira Green-Ruiz Felipe Amezcua-Linares 《Ichthyological Research》2006,53(1):70-74
Age and growth of the tropical flatfish Cyclopsetta querna were determined from the sagittal otoliths. From yearly marginal growth increment trends, it was concluded that the opaque
and hyaline zones were formed annually. The oldest individual was a 43.2-cm (5-year-old) female. No significant differences
in length-at-age were found between sexes. The von Bertalanffy growth equation for the entire population was Lt = 60.71 (1 − e (−0.245(t−0.408))). The life span of these species is short, about 5 years. The otoliths proved a reliable structure to determine age of this
species. 相似文献
11.
Lebeau T Gaudin P Junter GA Mignot L Robert JM 《Applied microbiology and biotechnology》2000,54(5):634-640
The marine diatom Haslea ostrearia was immobilized in a tubular agar gel layer introduced into a photobioreactor of original design with internal illumination
for the continuous synthesis of marennin, a blue-green pigment of biotechnological interest. Marennin was produced for a long-term
period (27–43 days) and the volumetric productivity was maximum (18.7 mg day−1 l−1 gel) at the highest dilution rate (0.25 day−1) and lowest agar layer thickness (3 mm). Heterogeneous cell distribution in the agar layer revealed diffusional limitation
of light and nutrients. However, the 3 mm gel thickness led to a more homogeneous cell distribution during incubation and
to an increase of the whole biomass in the agar gel layer.
Received: 22 October 1999 / Received revision: 14 February 2000 / Accepted: 18 February 2000 相似文献
12.
Jorge I. Sonnenholzner Gabriela Montaño-Moctezuma Ricardo Searcy-Bernal Alfredo Salas-Garza 《Journal of applied phycology》2011,23(3):505-513
Recently recruited urchins from the same brood, but with different initial sizes, may respond differently to similar environmental
factors. The aim of this study was to assess and compare the effects of starvation and diet on the survival, growth rates
in size and weight, and gonad index among small and large sub-adult purple sea urchins, Strongylocentrotus purpuratus. Small urchins ranged from 7.3 to 7.8 mm and large urchins from 11.8 to 14.1 mm (test diameters). Two independent experiments
were performed. In the first experiment, sea urchins were fed during 22 weeks on Egregia menziesii (ad libitum) and for only 1 day month−1 (starved condition). Feeding regime significantly affected survival, somatic growth rate in size and weight, and gonad index,
with higher means in the ad libitum treatments than in starving conditions. A recurrent cannibalism event by conspecifics
occurred in small sea urchins under starving conditions. In the second experiment, sea urchins were fed during 13 weeks ad
libitum with four diets: kelp (E. menziesii), coralline algae (Bossiella orbigniana), eelgrass (Phyllospadix scouleri) and a mixed diet of the three species. Survival was not affected by diet or urchin size, but diet significantly affected
somatic growth rate in size and weight and gonad index. Kelp promoted the highest growth rate (2.23 ± 0.21 mm month−1), the mixed diet produced an intermediate growth (1.26 ± 0.21 mm month−1), while the lowest values corresponded to coralline algae and the eelgrass (0.30 ± 0.12 and 0.10 ± 0.03 mm month−1, respectively, means ± SE). The mean growth rate of small urchins (averaging all diets) was higher than in large specimens
(1.17 ± 0.37 and 0.77 ± 0.28 mm month−1, respectively). 相似文献
13.
Removal of nitrate and phosphate ions from water, by using the thermophilic cyanobacterium Phormidium laminosum, immobilized on cellulose hollow fibres in the tubular photobioreactor at 43 °C, was studied by continuously supplying dilute
growth medium for 7 days and then secondarily treated sewage (STS) for 12 days. The concentrations of NO−
3 and PO3−
4 in the effluent from the dilute growth medium decreased from 5.0 mg N/l to 3.1 mg N/l, and from 0.75 mg P/l to 0.05 mg P/l
respectively, after a residence time of 12 h. The concentrations of NO−
3 and PO3−
4 in the effluent from STS decreased from 11.7 mg N/l to 2.0 mg N/l, and from 6.62 mg P/l to 0.02 mg P/l respectively, after
a residence time of 48 h. The removal rates of nitrogenous␣and phosphate ions from STS were 0.24 and 0.11 mmol day−1 l reactor−1 respectively, under the same conditions. Although, among nitrogenous ions, nitrate and ammonium ions were efficiently removed
by P.␣laminosum, the nitrite ion was released into the effluent when STS was used as influent. Treatment of water with thermophilic P. laminosum immobilized on hollow fibres thus appears to be an appropriate means for the removal of inorganic nitrogen and phosphorus
from treated wastewater.
Received: 15 August 1997 / Received last revision: 18 November 1997 / Accepted: 29 November 1997 相似文献
14.
Actual and potential rates of hydrogen photoproduction by continuous culture of the purple non-sulphur bacterium Rhodobacter capsulatus 总被引:1,自引:1,他引:0
A. A. Tsygankov A. S. Fedorov T. V. Laurinavichene I. N. Gogotov K. K. Rao D. O. Hall 《Applied microbiology and biotechnology》1998,49(1):102-107
The influence of (NH4)2SO4 concentration and dilution rate (D) on actual and potential H2 photoproduction has been studied in ammonium-limited chemostat cultures of Rhodobacter capsulatus B10. The actual H2 production in a photobioreactor was maximal (approx. 80 ml h−1 l−1) at D = 0.06 h−1 and 4 mM (NH4)2SO4. However, it was lower than the potential H2 evolution (calculated from hydrogen evolution rates in incubation vials), which amounted to 100–120 ml h−1 l−1 at D = 0.03–0.08 h−1. Taking into account the fact that H2 production in the photobioreactor under these conditions was not limited by light or lactate, another limiting (inhibiting)
factor should be sought. One possibility is an inhibition of H2 production by the H2 accumulated in the gas phase. This is apparent from the non-linear kinetics of H2 evolution in the vials or from its inhibition by the addition of H2; initial rates were restored in both cases after the vials had been refilled with argon. The actual H2 production in the photobioreactor at D = 0.06 h−1 was shown to increase from approximately 80 ml h−1 l−1 to approximately 100 ml h−1 l−1 under an argon flow at 100 ml min−1. Under maximal H2 production rates in the photobioreactor, up to 30% of the lactate feedstock was utilised for H2 production and 50% for biomass synthesis.
Received: 22 April 1997 / Received revision: 14 July 1997 / Accepted: 27 July 1997 相似文献
15.
Reina R 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2000,170(8):573-580
Microsphere and morphometric techniques were used to investigate any circulatory changes that accompany secretion by the
salt glands of hatchling Chelonia mydas. Salt glands were activated by a salt load of 27.0 mmol NaCl kg body mass (BM)−1, resulting in a mean sodium secretion rate of 4.14 ± 0.11 mmol Na kg BM−1 h−1 for a single gland. Microsphere entrapment was approximately 160–180 times greater in the active salt gland than the inactive
gland, inferring a similar change in blood flow through salt gland capillaries. The concentration of microspheres trapped
in the salt gland was significantly correlated with the rate of tear production (ml kg BM−1 h−1) and the total rate of sodium secretion (mmol Na kg BM−1 h−1) but not with tear sodium concentration (mmol Na l−1). Adrenaline (500 μg kg BM−1) inhibited tear production within 2 min and reduced microsphere entrapment by approximately 95% compared with active glands.
The volume of filled blood vessels increased from 0.03 ± 0.01% of secretory lobe volume in inactive salt gland sections to
0.70 ± 0.11% in active gland sections. The results demonstrate that capillary blood flow in the salt gland of C. mydas can regulate the activity of the gland as a whole.
Accepted: 12 July 2000 相似文献
16.
Margareth da Silva Copertino Thiago Tormena Ulrich Seeliger 《Journal of applied phycology》2009,21(1):31-45
The growth, biofiltering efficiency and uptake rates of Ulva clathrata were studied in a series of outdoor tanks, receiving waste water directly from a shrimp (Litopenaeus vannamei) aquaculture pond, under constant aeration and two different water regimes: (1) continuous flow, with 1 volume exchange a
day (VE day-1) and (2) static regime, with 1 VE after 4 days. Water temperature, salinity, pH, dissolved inorganic nitrogen (DIN), phosphate
(PO4), chlorophyll-a (chl-a), total suspended solids (TSS), macroalgal biomass (fresh weight) and tissue nutrient assimilation were monitored over 12 days.
Ulva clathrata was highly efficient in removing the main inorganic nutrients from effluent water, stripping 70–82% of the total ammonium
nitrogen (TAN) and 50% PO4 within 15 h. Reductions in control tanks were much lower (Tukey HSD, P < 0.05). After 3 days, the mean uptake rates by the seaweed biomass under continuous flow were 3.09 mg DIN g DW day−1 (383 mg DIN m−2 day−1) and 0.13 mg PO4 g DW day−1 (99 mg PO4 m−2 day−1), being significantly higher than in the static regime (Tukey HSD, P < 0.05). The chl-a decreased in seaweed tanks, suggesting that U. clathrata inhibited phytoplankton growth. Correlations between the cumulative values of DIN removed from the water and total nitrogen
assimilated into the seaweed biomass (r = 0.7 and 0.8, P < 0.05), suggest that nutrient removal by U. clathrata dominated over other processes such as phytoplankton and bacterial assimilation, ammonia volatilization and nutrient precipitation. 相似文献
17.
M. Wenk T. Baumgartner J. Dobovšek T. Fuchs J. Kucsera J. Zopfi G. Stucki 《Applied microbiology and biotechnology》1998,49(5):624-630
The evaluation of pesticide-mineralising microorganisms to clean-up contaminated soils was studied with the widely applied
and easily detectable compound atrazine, which is rapidly mineralised by several microorganisms including the Pseudomonas sp. strain Yaya 6. The rate of atrazine removal was proportional to the water content of the soil and the amount of bacteria
added to the soil. In soil slurry, 6 mg atrazine kg soil−1 was eliminated within 1 day after application of 0.3 g dry weight inoculant biomass kg soil−1 and within 5 days when 0.003 g kg soil−1 was used. In partially saturated soil (60% of the maximal water-holding capacity) 15 mg atrazine kg soil−1 was eliminated within 2 days by 1 g biomass kg soil−1 and within 25 days when 0.01 g biomass kg soil−1 was used. In unsaturated soil, about 60% [U-ring-14C]atrazine was converted to 14CO2 within 14 days. Atrazine was very efficiently removed by the inoculant biomass, not only in soil that was freshly contaminated
but also in soil aged with atrazine for up to 260 days. The bacteria exposed to atrazine in unsaturated sterile soil were
still active after a starvation period of 240 days: 15 mg newly added atrazine kg soil−1 was eliminated within 5 days.
Received: 31 October 1997 / Received revision: 16 January 1998 / Accepted: 18 January 1998 相似文献
18.
Rainfall partitioning into throughfall and stemflow was studied in a diverse and in a mono specific stand of secondary vegetation
in Eastern Amazonia. The nutrient concentrations in the water were analysed in order to quantify the related hydrochemical
fluxes. Secondary vegetation forms the fallow in the local shifting cultivation system and is usually dominated by shrubs
and trees. Phenakospermum guyannense (Strelitziaceae), a banana-like herb, is one of the predominant non-woody species. The study was conducted during an 18-month
period in a 2.5-year-old relatively species-rich stand and a 10-year-old stand dominated by P. guyannense. In a year with 1956 mm of rainfall 65% (1281 mm) of this quantity reached the soil as throughfall in the diverse stand and
38% (743 mm) in the mono specific stand. Stemflow was estimated to be 23% and 41% respectively. P. guyannense and Banara guianensis (Flacourtiaceae), a tree species, were causing these high funnelling effects. In the young diverse stand B. guianensis had a stemflow of more than 200 l year−1 and P. guyannense had a median flux of 77 l year−1 per pseudostem. In the older stand the taller plants of P.␣guyannense collected 644 l year−1 per pseudostem on the median. The reason for these high values could be the banana-like growth form of P. guyannense and the crown morphology of B. guianensis, which has inclined branches. The low proportion of throughfall and the high stemflow values differ from all previous studies
in Amazonian primary forests. The proximity to the Atlantic Ocean strongly influenced the nutrient fluxes via rainfall at
our study site. This becomes obvious from the high Na and Cl fluxes with rainfall (19.7 kg Na ha−1 year−1, 37.2 kg Cl ha−1 year−1) which were approximately equal to the Na and Cl fluxes with the sum of throughfall and stemflow for both stands. K fluxes
in throughfall and stemflow in both stands were higher than in rainfall by a factor of 8. The high K enrichment during the
crown passage is assumed to be caused by a␣high K concentration in the leaf tissue resulting in enhanced leaching from the
leaves. In months with low␣rainfall the concentrations of Ca, Mg, S and Cl in throughfall of the diverse stand were significantly
higher than in months with high rainfall. This was mainly due to vegetation burns in the dry period, which resulted in ash
deposition on the canopy and subsequent wash-off and solution of ash particles.
Received: 11 May 1997 / Accepted: 2 November 1997 相似文献
19.
Malaysia is the world’s leading producer of palm oil products that contribute US$ 7.5 billion in export revenues. Like any
other agro-based industries, it generates waste that could be utilized as a source of organic nutrients for microalgae culture.
Present investigation delves upon Isochrysis sp. culture in POME modified medium and its utilization as a supplement to Nanochloropsis sp. in rotifer cultures. The culture conditions were optimized using a 1 L photobioreactor (Temp: 23°C, illumination: 180 ∼ 200 μmol
photons m−2s−1, n = 6) and scaled up to 10 L outdoor system (Temp: 26–29°C, illumination: 50 ∼ 180 μmol photons m−2s−1, n = 3). Algal growth rate in photobioreactor (μ = 0.0363 h−1) was 55% higher compared to outdoor culture (μ = 0.0163 h−1), but biomass production was 1.3 times higher in outdoor culture (Outdoor = 91.7 mg m−2d−1; Photobioreactor = 69 mg m−2d−1). Outdoor culture produced 18% higher lipid; while total fatty acids (FA) was not significantly affected by the change in
culture systems as both cultures yield almost similar concentrations of fatty acids per gram of sample (photobioreactor = 119.17 mg
g−1; outdoor culture = 104.50 mg g−1); however, outdoor cultured Isochrysis sp. had 26% more polyunsaturated fatty acids (PUFAs). Rotifers cultured in Isochrysis sp./ Nanochloropsis sp. (1:1, v/v) mixture gave similar growth rate as 100% Nanochoropsis sp. culture (μ = 0.40 d−1), but had 45% higher counts of rotifers with eggs (t = 7, maximum). The Isochrysis sp. culture successfully lowered the nitrate (46%) and orthophosphate (83%) during outdoor culture. 相似文献
20.
Schizopygopsis younghusbandi younghusbandi is an endemic species whose distribution is restricted to the middle reaches of the Yarlung Zangbo River, being one of the
most important commercial fishes in this area. Age and growth of 606 specimens captured between October 2002 and April 2005
were studied. The range in standard length (L) was 65.7–387.3 mm and total weight (W) was 3.3–772.0 g. The relationship between
L and W was W = 0.000909L2.2493 for males and W = 0.000259L2.4781 for females. Age, determined from anal scales and lapillus otoliths, ranged from 3 to 18 years. The parameters of von Bertalanffy
growth functions, estimated by back-calculated length, were L¥ = 442.7mm LL_\infty = 442.7mm\;L, k = 0.0738 year−1 and t
0
= −1.4 year for males, and L¥ = 471.4mm LL_\infty = 471.4mm\;L, k = 0.0789 year−1 and t
0 = 0.2 year for females. Males and females exhibited statistically significant differences in growth. χ
2-test indicated that von Bertalanffy growth functions could well describe the growth of S. y. younghusbandi. The longevities were 39.2 and 38.2 years for males and females, respectively. Growth inflexion points were 10.2 and 12.0 years
for males and females, respectively, but 84.8% of the captures were at the smaller ages. So conservation and management schemes
for this population should be considered urgently. In addition, we found that populations from the upstream of the Lhasa River,
the downstream of the Lhasa River and the middle reaches of the Yarlung Zangbo River showed statistically significant differences
in growth patterns. 相似文献