Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 4 of 4
Full-Text Articles in Life Sciences
Life History And Population Dynamics Of The Opportunistic Polychaete Capitella Sp. I In Relation To Sediment Organic Matter, Tina Ramskov, Valery E. Forbes
Life History And Population Dynamics Of The Opportunistic Polychaete Capitella Sp. I In Relation To Sediment Organic Matter, Tina Ramskov, Valery E. Forbes
Valery E Forbes
Capitella sp. I is a deposit-feeding polychaete that occurs in estuarine and marine environments and that shows boom-bust population dynamics in response to organic pollution. A lifecycle experiment was carried out to quantify the relative importance of individual life-history traits for driving the dynamics of Capitella sp. I populations in response to changes in sediment organic matter concentrations. Individual-level effects were estimated as changes in survival, reproductive characteristics, and growth. Effects at the population-level were assessed by integrating the measured life-history traits in a simple 2-stage demographic model that was used to estimate the population growth rate (λ). Low organic …
Joint Effects Of Population Density And Toxicant Exposure On Population Dynamics Of Capitella Sp. I, Valery E. Forbes, Richard M. Sibly, Inez Linke-Gamenick
Joint Effects Of Population Density And Toxicant Exposure On Population Dynamics Of Capitella Sp. I, Valery E. Forbes, Richard M. Sibly, Inez Linke-Gamenick
Valery E Forbes
Very few studies have analyzed the dependence of population growth rate on population density, and even fewer have considered interaction effects of density and other stresses, such as exposure to toxic chemicals. Yet without such studies we cannot know whether chemicals harmful at low density have effects on carrying capacity or, conversely, whether chemicals reducing carrying capacity are also harmful at low density, impeding a population’s capacity to recover from disturbance. This study examines the combined effects of population density and a toxicant (fluoranthene) on population growth rate (pgr) and carrying capacity using the deposit-feeding polychaete Capitella sp. I as …
Density-Dependent Effects Of A Toxicant On Life-History Traits And Population Dynamics Of A Capitellid Polychaete, Inez Linke-Gamenick, Valery E. Forbes, Richard M. Sibly
Density-Dependent Effects Of A Toxicant On Life-History Traits And Population Dynamics Of A Capitellid Polychaete, Inez Linke-Gamenick, Valery E. Forbes, Richard M. Sibly
Valery E Forbes
The toxic effects of the widespread polycyclic aromatic hydrocarbon (PAH), fluoranthene (FLU), on Life-history traits of Capitella sp. M as a function of population density were investigated in a life-table-response-experiment (LTRE) lasting 134 d. Animals from laboratory cultures were exposed to 6 different FLU concentrations (range 0 to 80 μg FLU [g dry wt sed]–1, ppm) at 3 population densities (range 529 to 36 842 worms m–2), and survivorship, growth rate until maturity, and reproductive parameters were recorded. Fluoranthene exposure significantly reduced juvenile survivorship in a concentration- dependent manner, whereas population density had no effect on this trait. In contrast, …
Effects Of Chronic Fluoranthene Exposure On Sibling Species Of Capitella With Different Development Modes, Inez Linke-Gamenick, Valery E. Forbes, Nuria Méndez
Effects Of Chronic Fluoranthene Exposure On Sibling Species Of Capitella With Different Development Modes, Inez Linke-Gamenick, Valery E. Forbes, Nuria Méndez
Valery E Forbes
Toxic effects of the polycyclic aromatic hydrocarbon fluoranthene (FLU) on life-history traits and their demographic consequences were investigated in 3 non-interbreeding Capitella sibling species with different physiological tolerances and developmental modes: sensitive Capitella sp. S from oxygen-rich intertidal sediments of the North Sea (Germany); tolerant Capitella sp. M from sediments near shallow hydrothermal vents off Milos (Greece), a habitat low in organic matter with steep abiotic gradients and high sulfide concentrations; tolerant Capitella sp. I from New York (USA), known to dominate eutrophicated/polluted environments. Both Capitella spp. M and I can develop into hermaphrodites and have lecithotrophic larval development. In …