Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 4 of 4
Full-Text Articles in Life Sciences
Biological Aspects Of Heat Pollution, Theodore Olson
Biological Aspects Of Heat Pollution, Theodore Olson
Journal of the Minnesota Academy of Science
The importance of temperature as an environmental factor has long been recognized by the ecologist, and its special impact upon the aquatic ecosystem has been of interest to aquatic biologists since they first began to observe interactions between living things and the physical environment. Interest in water temperatures as an environmental factor has recently become more widespread; and one aspect of the phenomenon, namely "thermal pollution," has attracted special attention.
Some Aspects Of The Symbionts Of Cassiopeia Frondosa, Dolores Ahles O.S.F.
Some Aspects Of The Symbionts Of Cassiopeia Frondosa, Dolores Ahles O.S.F.
Journal of the Minnesota Academy of Science
Symbiodinium microadriaticum were found localized in the mesoglea of Cassiopeia, the upside-down jellyfish. Axenic cultures of the symbiont were produced, utilizing chemically defined media. Studies of the life cycle established the presence of isogametes which had previously been postulated. Reactions to various bands of the spectrum were noted, and tolerance tests for survival in darkness and under temperature stress were carried out. Nutritional experiments established nitrates as the best nitrogen source and verified the fact that vitamins B12 and Thiamine, though not essential far life, hove a stimulating effect on the growth and motility of these zooxanthellae.
Distribution And Abundance Of Molluscs In A Fresh Water Environment, Peter Moyle, James Bacon
Distribution And Abundance Of Molluscs In A Fresh Water Environment, Peter Moyle, James Bacon
Journal of the Minnesota Academy of Science
The molluscs of o northwestern Minnesota lake were sampled using transects, a sampling frame, and SCUBA. The species sampled were: Amnicola limosa, Valvata tricarinata, Gyraulus parvus, Physa cf. P. gyrina, Helisoma anceps, H. campanulata, Promenetus exacuous, Ferrissia parallela, Anodonta marginata, Lampsilis siliquoidea, and Sphaerium cf. S. striatum. The unionid clams, the adult Helisoma spp. and the Physa adults were associated with the absence of aquatic vegetation. Distinct associations of snail species were found with each plant association: G. parvus and V. tricarinata with the deep water Nitella opaca association, A. limosa and V. tricarinata with the mid-depth mixed macrophyte association, …
Characteristics Of Four Marl Lakes As Related To Biological Productivity, J. E. Maloney, John Dobie, John B. Moyle
Characteristics Of Four Marl Lakes As Related To Biological Productivity, J. E. Maloney, John Dobie, John B. Moyle
Journal of the Minnesota Academy of Science
Physical and chemical characteristics of four dimictic eutrophic lakes of northcentral Minnesota with marl deposits are discussed in relation to production of invertebrate animals (benthos and plankton) that are the basic food of fish . Two of the lakes have a history as "productive" fish lakes and the other two as "problem" fish lakes. The "productive" lakes, as a type, have a larger surface area, a longer shallow-water littoral shelf, and a lower proportion of marly soils in the littoral zone than do the "problem" lakes. The standing crop of invertebrates was about twice as great per habitat unit in …