Population Dynamics of Limnetic Cladocera in a Beaver Pond

1975 ◽  
Vol 32 (3) ◽  
pp. 341-346 ◽  
Author(s):  
Judith K. Kwik ◽  
John C. H. Carter
Keyword(s):  
Population Dynamics ◽  
Embryonic Development ◽  
Carrying Capacity ◽  
Sampling Errors ◽  
Beaver Pond ◽  
Bosmina Longirostris ◽  
Georgian Bay ◽  
Development Times ◽  
Different Temperatures ◽  
Ceriodaphnia Quadrangula

In a small, shallow, predation free beaver pond near Georgian Bay, Ontario Ceriodaphnia quadrangula was monacmic and Daphnia ambigua and Bosmina longirostris triacmic. Each species peaked and declined rapidly, presumably overshooting the carrying capacity of a food limited environment. Embryonic development times of each species at different temperatures was determined in the laboratory and fitted with Bĕlahrádek’s function. Calculated instantaneous rates of birth and death were normal for D. ambigua and C. quadrangula but too low to account for the rapid fluctuations in numbers of B. longirostris, suggesting occasional gross sampling errors. Bosmina longirostris may periodically abandon the limnoplankton for a benthic existence thus avoiding capture.

scholarly journals Determination of Load-Carrying Capacity of C-Profile Glued Ti-Al Column under Temperature Environment

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3013
Author(s):  
Leszek Czechowski
Keyword(s):  
Carrying Capacity ◽  
Tensile Tests ◽  
Discrete Models ◽  
Image Correlation ◽  
Load Carrying Capacity ◽  
Lagrange Equations ◽  
Load Carrying ◽  
Different Temperatures ◽  
Influence Of Temperature On

The paper deals with an examination of the behaviour of glued Ti-Al column under compression at elevated temperature. The tests of compressed columns with initial load were performed at different temperatures to obtain their characteristics and the load-carrying capacity. The deformations of columns during tests were registered by employing non-contact Digital Image Correlation Aramis® System. The numerical computations based on finite element method by using two different discrete models were carried out to validate the empirical results. To solve the problems, true stress-logarithmic strain curves of one-directional tensile tests dependent on temperature both for considered metals and glue were implemented to software. Numerical estimations based on Green–Lagrange equations for large deflections and strains were conducted. The paper reveals the influence of temperature on the behaviour of compressed C-profile Ti-Al columns. It was verified how the load-carrying capacity of glued bi-metal column decreases with an increase in the temperature increment. The achieved maximum loads at temperature 200 °C dropped by 2.5 times related to maximum loads at ambient temperature.

Thermal influence on the embryonic development and hatching rate of the flameback pygmy angelfish Centropyge aurantonotus eggs

Zygote ◽  
2019 ◽  
Vol 28 (1) ◽  
pp. 80-82
Author(s):  
Raoani Cruz Mendonça ◽  
Sarah Pittigliani Ikebata ◽  
Sérgio Leandro Araújo-Silva ◽  
João Vitor Azevedo Manhães ◽  
Mônica Yumi Tsuzuki
Keyword(s):  
Embryonic Development ◽  
Incubation Temperature ◽  
Abiotic Factors ◽  
Environmental Parameters ◽  
Hatching Rate ◽  
Influence Of Temperature ◽  
Different Temperatures ◽  
Influence Of Temperature On ◽  
Thermal Influence ◽  
Hatching Rates

SummaryThe flameback pygmy angelfish Centropyge aurantonotus, highly appreciated and valued by the aquarium market, is heavily harvested and traded. Temperature is one of the abiotic factors that has the most influence on fish development, especially in the early stages of life. For captive production, it is essential to know the appropriate environmental parameters for each species. In this sense, this study aimed to evaluate the influence of temperature on the embryonic development and hatching rates of C. aurantonotus incubated at six different temperatures (20, 22, 24, 26, 28, 30°C). Embryonic development events were very similar in terms of morphological and chronological characteristics compared with other species of the genus Centropyge. Incubation time was inversely proportional to temperature. The treatment at 22°C required twice the time of that required by 30°C treatment for hatching to occur. The best incubation temperature range was 24–28°C. Values below 22°C and at 30°C showed lower hatching rates compared with other treatments. Based on these results, the recommended temperature at which to incubate C. aurantonotus eggs is between 24–28°C.

The role of blood intake in density regulation of populations of Triatoma infestans (Klug) (Hemiptera: Reduviidae)

1982 ◽  
Vol 72 (4) ◽  
pp. 617-629 ◽  
Author(s):  
C. J. Schofield
Keyword(s):  
Population Density ◽  
Triatoma Infestans ◽  
Female Fecundity ◽  
Density Regulation ◽  
Dependent Relationship ◽  
Development Times ◽  
Different Temperatures ◽  
Development Processes ◽  
The Difference

AbstractThe growth of populations of Triatoma infestans (Klug) depends on temperature and blood-intake. Experiments are described which demonstrated the density-dependent relationship between population size, blood intake and population growth at different temperatures. The number of bugs feeding and their mean blood intake was lower at high bug densities than at low ones, both with restrained chickens and with unrestrained mice as hosts. When blood intake was restricted, the development times of all nymphal stages were increased, and female fecundity was decreased. Previous work showed also that reduced blood intake led to an increased tendency for adult flight. It is thought that at high bug density the three factors, increased development times, decreased fecundity and increased flight, operate to restore the population to a stable density without promoting an increase in mortality. The mechanism linking population density to nutritional status seemed to depend on host irritability, which interrupted the bugs' feeding. Bugs which passed a certain threshold meal size would not resume feeding if interrupted, even though their blood intake was well below normal. The difference between the minimal threshold meal and a normal meal is thought to provide the nutritional elasticity within which the development processes are regulated. It is suggested that this mechanism is characteristic of K-strategists, whereas r–strategists such as mosquitoes tend to continue attacking, even if interrupted, until they achieve a normal meal.

Effect of temperature on embryonic development of Melanotaenia boesemani (Allen and Cross, 1982)

Zygote ◽  
2015 ◽  
Vol 24 (2) ◽  
pp. 301-309 ◽  
Author(s):  
Marcella Costa Radael ◽  
Leonardo Demier Cardoso ◽  
Dalcio Ricardo de Andrade ◽  
André Veloso Ferreira ◽  
Douglas da Cruz Mattos ◽  
...  
Keyword(s):  
Embryonic Development ◽  
Effect Of Temperature ◽  
Hatching Rate ◽  
Oil Droplets ◽  
Development Stages ◽  
Different Temperatures ◽  
Effects Of Temperature ◽  
The Moment ◽  
Time Required ◽  
Faster Development

SummaryThe present study aimed to provide data on the time required for Melanotaenia boesemani to complete embryonic development, and to investigate the influence that incubation at different temperatures caused in this species. The effects of temperature on the time and hatching rate are presented, as well as information related to embryonic development stages. After fertilization, the eggs were kept in incubators at 23, 26, 29 or 32°C and observed at predetermined times until the moment of hatching. Stages of development were identified and classified according to morphological and physiological characteristics. Oil droplets were visualized inside the eggs as well as filament adhesion present at the chorion. Embryonic development was similar to that observed in other species of the genus Melanotaenia with hatching and faster development in higher temperatures.

Embryonic development of the newt Triturus italicus in relation to temperature

1998 ◽  
Vol 19 (4) ◽  
pp. 345-355 ◽  
Author(s):  
S. Tripepi ◽  
F. Rossi ◽  
G. Peluso
Keyword(s):  
Embryonic Development ◽  
Development Time ◽  
Normal Development ◽  
Different Temperatures

AbstractThe embryonic development of Triturus italicus was observed at different temperatures. Normal development occurred between 10°C and 22.5°C. In this range of temperatures an hyperbolic relationship between development time and temperature was confirmed.

scholarly journals Hierarchical modelling of temperature and habitat size effects on population dynamics of North Atlantic cod

2010 ◽  
Vol 67 (5) ◽  
pp. 833-855 ◽  
Author(s):  
Irene Mantzouni ◽  
Helle Sørensen ◽  
Robert B. O'Hara ◽  
Brian R. MacKenzie
Keyword(s):  
Population Dynamics ◽  
North Atlantic ◽  
Carrying Capacity ◽  
Size Effects ◽  
Atlantic Cod ◽  
Ecosystem Approach ◽  
Reproductive Rate ◽  
Model Parameters ◽  
Habitat Size ◽  
Hierarchical Modelling

Abstract Mantzouni, I., Sørensen, H., O'Hara, R. B., and MacKenzie, B. R. 2010. Hierarchical modelling of temperature and habitat size effects on population dynamics of North Atlantic cod. – ICES Journal of Marine Science, 67: 833–855. Understanding how temperature affects cod (Gadus morhua) ecology is important for forecasting how populations will develop as climate changes in future. The effects of spawning-season temperature and habitat size on cod recruitment dynamics have been investigated across the North Atlantic. Ricker and Beverton and Holt stock–recruitment (SR) models were extended by applying hierarchical methods, mixed-effects models, and Bayesian inference to incorporate the influence of these ecosystem factors on model parameters representing cod maximum reproductive rate and carrying capacity. We identified the pattern of temperature effects on cod productivity at the species level and estimated SR model parameters with increased precision. Temperature impacts vary geographically, being positive in areas where temperatures are <5°C, and negative for higher temperatures. Using the relationship derived, it is possible to predict expected changes in population-specific reproductive rates and carrying capacities resulting from temperature increases. Further, carrying capacity covaries with available habitat size, explaining at least half its variability across stocks. These patterns improve our understanding of environmental impacts on key population parameters, which is required for an ecosystem approach to cod management, particularly under ocean-warming scenarios.

scholarly journals Temporal development of Drosophila embryos is highly robust across a wide temperature range

2018 ◽  
Author(s):  
Jeronica Chong ◽  
Christopher Amourda ◽  
Timothy E. Saunders
Keyword(s):  
Embryonic Development ◽  
Local Environment ◽  
Morphogen Gradient ◽  
Temporal Development ◽  
Developmental Systems ◽  
History Dependence ◽  
Wide Range ◽  
Different Temperatures ◽  
Species Specific ◽  
Drosophila Embryos

AbstractDevelopment is a precisely coordinated process in both space and time. Spatial precision has been quantified in a number of developmental systems, and, for example, such data has contributed significantly to our understanding of morphogen gradient interpretation. However, comparatively little quantitative analysis has been performed on timing and temporal coordination during development. Here, we use Drosophila to explore the temporal robustness of embryonic development within physiologically normal temperatures. We find that development is temporally very precise across a wide range of temperatures in all three Drosophila species investigated. However, we find temperature dependence in the heterochronicity. A simple model incorporating history-dependence can explain the developmental temporal trajectories. Interestingly, the history-dependence is temperature specific with either effective negative or positive feedback at different temperatures. We also find that embryos are surprisingly robust to shifting temperatures during embryogenesis. We further identify differences between tropical and temperate species that are suggestive of different potential mechanisms regulating temporal development depending on the local environment. Overall, our data shows that Drosophila embryonic development is temporally robust across a wide range of temperatures but there are species specific differences.

Sign in / Sign up

Export Citation Format

Share Document