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In the past, diatoms were considered the primary food source for copepods in both wild and aquaculture settings. However, recent studies have found that diatoms have defense mechanisms against predators, making them unsuitable as copepod feed. This study assessed the impact of addition of 100 μg L−1 of silicate to an inorganic nutrition formula containing 700 μg L−1 nitrogen, 100 μg L−1 phosphorus, and 100 μg L−1 iron. Our objective was to assess the impact of increased diatom abundance on copepod production. The experiment was carried out in 1000 L outdoor tanks over a period of 20 days, with adult Pseudodiaptomus annandalei copepods, introduced into each tank on the second day at an initial density of 10 ind. L−1. The results indicated that adding silicate reduced the prevalence of Chlorophyta, replaced by a higher proportion of Dinophyta, and eventually dominated by diatoms. While silicate had a positive effect on diatom culture, it had a negative effect on copepod production. Adding silicate to the inorganic fertilization method resulted in increased costs, leading to a significant increase in the unit production cost of copepods. [ABSTRACT FROM AUTHOR]

The influences of a tidal cycle on the distribution of autotrophic plankton were investigated in a hyper-eutrophic lagoon designated as a scenic area. Results showed that the highest concentrations of picoplankton and phytoplankton were found in the middle and inner part of the lagoon, irrespective of the tides. The MDS result also revealed that phytoplankton communities, dominated by Ceratium furca, were similar among stations in the inner bay during both flood tides and ebb tides. The time series sampling results at the inlet-outlet channel revealed that almost the same amounts of phytoplankton and picoplankton were carried through the channel during flood and ebb tides, with no trend in nutrient fluctuations except for phosphate which had a net loss from the lagoon. The results showed that tidal cycles do not effectively flush away phytoplankton and picoplankton from the lagoon, and the blooming of phyto- and picoplankton is inevitable should the situation stay the same. Steps are needed to alleviate the eutrophication condition instead of depending on the natural process such as tidal cycle. [ABSTRACT FROM AUTHOR]

Examines the impact of the 1999 earthquake on mountain stream fishes in Taiwan. Size composition of the population of two dominant endemic fishes; Reason for the visibility of large adults in the pool after the earthquake; Reduction of the number of juveniles.