The seasonal cycles and vertical distribution of tintinnines in Bedford Basin, Nova Scotia, Canada

1987 ◽  
Vol 65 (1) ◽  
pp. 41-48 ◽  
Author(s):  
Madhu A. Paranjape
Keyword(s):  
Nova Scotia ◽  
Vertical Distribution ◽  
Seasonal Cycle ◽  
Late Summer ◽  
Survival Strategies ◽  
Late Winter ◽  
Seasonal Cycles ◽  
The Vertical Distribution ◽  
Fixed Station

The vertical distribution and seasonal cycle of tintinnine species were studied in Bedford Basin at a fixed station on 60 visits over an 18-month period. About 23 species of tintinnines belonging to 9 families were identified but only 12 were numerically dominant. Maximal numbers (102 to 104/L) were found in late summer and fall and minimal numbers (101 to 102/L), in late winter. The hyaline species of tintinnines occurred mostly in summer and fall, while agglomerated species dominated during other seasons. The total tintinnines contributed 35% (range, 3 to 55%) numerically and 2.5% (range, 0.05 to 16%) in terms of carbon to the microzooplankton in the Bedford Basin. The survival strategies employed by some species of tintinnines reasonably explain their seasonal cycle of abundance.

BIOLOGY AND BEHAVIOR OF ZIMMERMAN PINE MOTH, DIORYCTRIA ZIMMERMANI, IN MICHIGAN

1967 ◽  
Vol 99 (5) ◽  
pp. 529-536 ◽  
Author(s):  
R. B. Carlson ◽  
J. W. Butcher
Keyword(s):  
Life History ◽  
Vertical Distribution ◽  
Uniform Distribution ◽  
Late Summer ◽  
Head Capsule ◽  
Early Summer ◽  
Main Stem ◽  
History Of ◽  
And Behavior ◽  
The Vertical Distribution

AbstractThis paper reports on studies of biology and life history of the Zimmerman pine moth, Dioryctria zimmermani (Grote), in southern Michigan.Adults emerged during the last 3 weeks of August and eggs hatched through mid-September. Eggs were laid almost entirely on the main stem and, upon hatching, the larvae entered recesses in the bark and spun hibernacula, ostensibly without feeding.Studies on the vertical distribution of larvae and pupae showed a fairly uniform distribution over the main stem in spring and early summer. In late summer, a larger percentage was found in middle whorls.Based on head capsule measurements, it is tentatively proposed that there are six larval stadia. Occurrence of parasitism in the last larval stadia is discussed, and a new egg parasite is reported.The presence of D. abietivorella Grote in the study areas is noted, and discussed briefly.

scholarly journals Seasonal variation in the vertical distribution of zone over Oakshin Gangotri, Antarctica

MAUSAM ◽  
2021 ◽  
Vol 42 (3) ◽  
pp. 275-278
Author(s):  
A.L. KOPPAR ◽  
S.C. NAGRATH
Keyword(s):  
Seasonal Variation ◽  
Vertical Distribution ◽  
Early Spring ◽  
The Other ◽  
Late Winter ◽  
Double Peak ◽  
The Vertical Distribution

Ozone soundings made from Dakshin Gangotri, Antarctica during 1987 are presented. The vertical distribution of ozone over Antarctica is characterised by a double peak profile, one around 200-150 hPa and the other around 50 hPa. During late winter-early spring the upper peak is considerably depleted. Tropospheric ozoe remains low and nearly constant throughout the year.  

scholarly journals Vertical and seasonal distribution of eight Clausocalanus species (Copepoda: Calanoida) in oligotrophic waters

2004 ◽  
Vol 61 (4) ◽  
pp. 645-653 ◽  
Author(s):  
Àurea Peralba ◽  
Maria Grazia Mazzocchi
Keyword(s):  
Vertical Distribution ◽  
Quantitative Data ◽  
Environmental Parameters ◽  
Seasonal Distribution ◽  
Ecological Niches ◽  
Seasonal Cycles ◽  
Tyrrhenian Sea ◽  
Gulf Of Naples ◽  
Offshore Station ◽  
The Vertical Distribution

Abstract Copepods of the genus Clausocalanus Giesbrecht, 1888 are among the most abundant calanoids in the Mediterranean Sea, both in coastal and offshore regions. The vertical distribution of C. arcuicornis, C. furcatus, C. jobei, C. lividus, C. mastigophorus, C. parapergens, C. paululus, and C. pergens, which co-occur in the upper 200 m in the Gulf of Naples (Tyrrhenian Sea), was investigated during an annual sampling cycle conducted at an offshore station in 2002. The quantitative data on distribution of each species were analysed in relation to the environmental parameters. The patterns that we observed in the seasonal cycles and vertical distribution provided insights on the ecological niches of the eight Clausocalanus species.

Vertical distribution of Benthic Invertebrates in the Bed of the Thomson River, Victoria

1988 ◽  
Vol 39 (6) ◽  
pp. 775 ◽  
Author(s):  
R Marchant
Keyword(s):  
Vertical Distribution ◽  
Benthic Invertebrates ◽  
Benthic Fauna ◽  
Late Summer ◽  
Sample Surface ◽  
Depth Range ◽  
The Vertical Distribution ◽  
Surber Sampler

The vertical distribution of the benthic fauna was studied at three sites on the Thomson River using a freeze-corer. Samples were taken over two years in early and late summer. At each site an average of 72 to 84% of the fauna was found in the 0-10 cm zone of the riverbed, 10-20% in the 10-20 cm zone and 6-8% in the 20-30 cm zone; flooding at one site was followed by an increase in the depth to which the fauna penetrated. Surface percentage abundances were probably underestimated because of the inability of the corer to sample surface rocks and their fauna consistently and because the coring operation disturbs the surface fauna to some extent before it can be frozen. Nevertheless, the results indicate that in the Thomson River the majority of the fauna is within the depth range (0-10 cm) of a Surber sampler.

scholarly journals Measuring the vertical distributional variability of pelagic fauna in Monterey Bay

2012 ◽  
Vol 69 (2) ◽  
pp. 184-196 ◽  
Author(s):  
Samuel S. Urmy ◽  
John K. Horne ◽  
David H. Barbee
Keyword(s):  
Vertical Distribution ◽  
Temporal Variability ◽  
Signal Frequency ◽  
Late Winter ◽  
Monterey Bay ◽  
Analysis Techniques ◽  
Long Time ◽  
Autumn And Winter ◽  
The Vertical Distribution ◽  
Image Analysis Techniques

Abstract Urmy, S. S., Horne, J. K., and Barbee, D. H. 2012. Measuring the vertical distributional variability of pelagic fauna in Monterey Bay. – ICES Journal of Marine Science, 69: 184–196. Temporal variability is an important feature of aquatic ecosystems that can be difficult to measure. A stationary, upward-facing scientific echosounder was used to record the vertical distribution of pelagic fauna in Monterey Bay, CA, for 18 months. To characterize the distributions, a suite of metrics, including measures of density, abundance, location, dispersion, occupancy, evenness, and aggregation, was developed and tested. An algorithm to detect and count the number of acoustic backscatter layers was developed using image-analysis techniques. The metrics recorded a strong seasonal cycle, with total backscatter reaching a minimum during the spring upwelling season and peaking in autumn and winter. Variability in the vertical distribution of animals was greatest at long time-scales and decreased as a power (−1.050 to −1.585) of signal frequency. There were significant peaks in the power spectrum at 12- and 24-h periods, corresponding to the semi-diurnal tide and diel vertical migration. The diel signal was strongest in late winter and weakest during the spring upwelling season. Active acoustics are a useful addition to ocean observatories, and the metrics presented provide a useful set of tools to quantify the distribution and temporal variability of pelagic fauna.

Sign in / Sign up

Export Citation Format

Share Document