In opposition to toxicology of mammals piscine toxicology is closely connected with the conditions of external environment. The aquatic environment is necessary for embryonic development and after hatching during short or long-lasting larval period of most fish species. An aquatic environment is polluted by many industrial and agricultural wastes. Ammonia as a toxic and common compound in water...

The results of more than twenty years of own research and state environmental protection authority reports show that from 1986–2009 the quality of water in the lower Vistula, representative of the eastern (right bank) part of Poland, continuously and significantly improved. This improvement was the result of changes in water and sewage management in the Vistula basin. Earlier, in the 1970s, the...

iv FOREWORD Chapters 2, 3, 4, and 5 are either in review, in revision or will be submitted, and thus are formatted according to specific journal formats: Ecology (Chapter 1), Hydrobiologia Food webs and aquatic ecology of subtropical South American streams are poorly understood. I investigated the trophic structure of the upper Rio Cuareim (Uruguay, South America). I analyzed the stable isotope...

—Stream temperature regimes are fundamentally important to understanding patterns and process in aquatic ecosystems and inexpensive digital sensors enable accurate and repeated measurements of temperature at a site. Most temperature measurements in mountain streams are made only during summer months because of logistical constraints associated with stream access and concerns that large annual f...

Rates of oxygen production and inorganic carbon uptake by a mixed culture of phytoplankton were determined in a highly variable light regime. Scatter diagrams ofthe results revealed a smoothly varying relationship between irradiance and photosynthetic oxygen release except when the rate of oxygen release was depressed by CO2 depletion. There was no indication that the instantaneous rate of oxyg...

In the size range from lO-4 to 10’ pg (carbon) body weight, the biomass of plankton in the euphotic layer of the North Pacific Central Gyre decreases as an allometric function of body weight. Even in a steady state ecosystem such as that analyzed here, there is variability in space and time; this suggests that one must be careful in extrapolating the relation to less predictable marine areas. I...

We conducted a series of experiments feeding Daphnia pulex nine different phytoplankton monocultures with widely varying fatty acid composition and nutritional values to test the extent to which Daphnia fatty acid composition was affected by diet. In general, Daphnia fatty acid composition matched that of their diet much more closely than it did the fatty acid composition of Daphnia consuming o...

A field study in a boreal lake using a remotely operated vehicle equipped with a camera established that falling fish carcasses did not tend to be buried in sediments after deposition. Decomposition rates of fish carcasses in three boreal lakes were experimentally assessed at different depths. In shallow waters (between 0 and 4 m), decomposition was fast (half lives, t, ranging from 40 to 230 h...

A turbulent diffusion model shows that there are two different mechanisms for the development of phytoplankton blooms. One of these mechanisms works in well-mixed environments and corresponds to the classical critical depth theory. The other mechanism is based on the rate of turbulent mixing. If turbulent mixing is less than a critical turbulence, phytoplankton growth rates exceed the vertical ...

The biodegradation of organic matter ingressing spawning gravels in rivers exerts an oxygen demand which is believed to contribute to detrimental impacts on aquatic ecology including salmonids. Catchment management strategies therefore require reliable information on the key sources of sediment-bound organic matter. Accordingly, a novel source fingerprinting procedure based on analyses of bulk ...