Study On Energy Budgets And Carrying Capacity Of Perna Viridis(Linnaeus)

Basing on the measurement of ingestion, excretion, respiration rate, and assimilatory efficiency of Perna viridis in aquaria, energy budgets of mussel, in relation to body size, food concentrations of the unicellular green alga Platymonas subcordjformis, were established. Then the carrying capacity of Perna 憊iridis in a cultivating area was estimated. The ingestion, respiration and excretion rate of Perna viridis decreased with increase in body size. But absorption efficiency changed slightly independent of body size. In ingestive energy or assimilatory energy ,the percent disposable for growth decreased when body sizes of mussel increased.The highest energy budget was obtained at the smallest body size. The influence of food concentration on these four physical rates of mussel was studied. The ingestion, inspiration, excretion rate increased gradually at higher food concentration ranging from 500 to S000cells/rnL.But increased food concentration did not significantly affect the absorption efficiency. The energy flowed into growth of mussel was limited at low food concentration .The higher food concentration was supplied ,the higher energy budget of mussel was reached. What's more, these physical rates identified differently in environmental temperatures designed. The ingestion, respiration, excretion rate increased with the increasing of temperature. However, the absorption efficiency was stable in different temperatures. Each component of the energy differed in different temperature. The percentage of growth energy was small at lower temperatures, but it was large at higher temperatures. We conclude that Perna viridis is a high adaptable suspension feeder and it can filter the coastal sestons with high efficiency. Perna viridis cultivated in a sea area could eliminate phytoplanton greatly, and we could control the biomass of the algae to purify the water of the culturing area. So Perna viridis can be cultivated with the aim of controlling the eutrophication of the culturing area and gaining the ideal cultivating production. For example ,if the level of the organic suspension particles was 3.055mg/L, carrying capacity of perna viridis should be 62 individuals/rn2. Then in whole Dapen Bay whose cultivating area is 17.2 km2,the maximum of mussel was 1.068 X 1 O~ individuals.