The Experts below are selected from a list of 237 Experts worldwide ranked by ideXlab platform

Hans-peter Grossart - One of the best experts on this subject based on the ideXlab platform.

Jotaro Urabe - One of the best experts on this subject based on the ideXlab platform.

  • effect of food concentration on the carbon balance of Bosmina longirostris crustacea cladocera
    Freshwater Biology, 1991
    Co-Authors: Jotaro Urabe
    Abstract:

    SUMMARY. 1. The carbon balance of the small cladoceran, Bosmina longirostris, was examined at four food concentrations (0,05, 0.10, 0.25, 2.50mg C 1-−1) based on long-term growth experiments. 2. At birth, B. longirostris allocated about 60% of assimilation to body growth at all food concentrations. However, allocation to body growth decreased with age and was less than 5% after the fourth instar at the lowest food concentration. The proportion allocated to reproduction increased with increasing food concentration, but was relatively constant among different adult instars. 3. Assimilation rate increased with increasing food concentration and increasing body size: the mean rate from birth to 15 days was 6.6 times higher at the highest food concentration than at the lowest food concentration. However, with decreasing food concentration and increasing body size, a higher proportion of the assimilated carbon was lost as respiration. As a result, the net production rate reached a plateau at intermediate body size and was 9.1 times higher at the highest food concentration than at the lowest food concentration. 4. Comparison with previous studies revealed that B. longirostris is more efficient than Daphnia with regard to carbon production, especially at low food conditions, if the death rate is negligible.

  • effect of food concentration on growth reproduction and survivorship of Bosmina longirostris cladocera an experimental study
    Freshwater Biology, 1991
    Co-Authors: Jotaro Urabe
    Abstract:

    SUMMARY. 1. Body growth, reproduction and survivorship of Bosmina longirostris were monitored at four food concentrations (0.05, 0.10, 0,25 and 2.50 ing Cl−1) to examine the extent to which food concentration affects these life-history parameters. 2. Food concentration had a significant effect on growth, and most of the reproductive parameters (size and age at maturation, brood size, instar duration and egg development time). More than 60% of animals died before maturation at the lowest food concentration, although most animals survived until maturation at other food concentrations. 3. Change in life-history parameters resulted in a decrease in rate of population growth (r) from 0.310 to 0.020 day−1 with decreasing food concentration, showing that this cladoceran is highly food-limited in many lakes. 4. Importance of the effect of food concentration on egg development time was emphasized in relation to analysis of natural populations.

Olga P. Dubovskaya - One of the best experts on this subject based on the ideXlab platform.

Erin K. Field - One of the best experts on this subject based on the ideXlab platform.

  • The effects of temperature on Bosmina longirostris susceptibility to microcystin-LR acute toxicity.
    PLOS ONE, 2019
    Co-Authors: Madison C. Lamb, David G. Kimmel, Erin K. Field
    Abstract:

    : Harmful algal blooms are an ongoing threat to many aquatic systems throughout the world. In the Chowan River, North Carolina, the frequency of toxin producing Microcystis aeruginosa blooms has increased since 1975 along with an average 0.71°C rise in water temperature. The combined effect of microcystin-LR toxin and rising temperatures on a dominant zooplankter in the system, Bosmina longirostris, was the focus of this study. Laboratory studies were conducted to determine how microcystin-LR, produced from M. aeruginosa blooms, affected B. longirostris mortality under different temperature regimes. At 25°C, the LC50 for B. longirostris was 26.3 μg L-1 suggesting that B. longirostris can survive typical current bloom microcystin-LR concentrations ranging 0.1μg L-1 to 2.0 μg L-1, but would be susceptible to higher concentrations they may be periodically exposed to. Mortality was assessed at a constant microcystin-LR concentration of 26.3 μg L-1 over 15-35°C, and it was found that B. longirostris mortality increased at higher temperatures. B. longirostris mortality increased approximately 18% due to microcystin-LR alone over 2°C between 25°C and 27°C when exposed to the LC50 concentration. The increased prevalence of toxic M. aeruginosa blooms and increasing temperatures due to climate change may reduce B. longirostris populations, potentially affecting larval fish and fisheries in the Chowan River, North Carolina.

Hillary M. Masundire - One of the best experts on this subject based on the ideXlab platform.