Hackstock-Schellenberg, Franz: Die Süßwasserfische Mitteleuropas und ihr Fang. Leitfaden für Sportfischer und solche, die es werden wollen. – 1964. Mit 118 Bildern u. 14 Tafeln. – Rüschlikon-Zürich, Stuttgart, Wien: Albert Müller Verlag 1964. 212 S. Fr. 17.80

✍ Scribed by H. Caspers

• Publisher: John Wiley and Sons
• Year: 1966
• Tongue: English
• Weight: 95 KB
• Volume: 51
• Category: Article
• ISSN: 1434-2944
• DOI: 10.1002/iroh.19660510117

✦ Synopsis

Buchbesprechungen

of LORENZEN are perhaps the most satisfactory". -Bei der Analyse der saisonalen Sukzessionen im Gewasser wird auch die Bedeutung der Selektion durch algenfressende Zooplankter hervorgehoben. "The general picture seems t o be that at the beginning of the growing season the water is rich i n nutrients and behaves rather like a n ordinary artificial culture medium containing only inorganic constituents. . . The most rapidly growing species then becomes dominant. As a result of this growth, mineral nutrients are depleted, and organic by-products of metabolism begin t o accumulate. Consequently, the species which now succeed are not the most rapidly growing but those which are best able t o make use of the organic matter. In such a community we might expect interrelations among species to be complex and the number of species consequently high. Increased stability of the water column and reduction of mixing a t this stage result in reduced rates of growth and permit, discrete clouds of organisms t o be formed and to persist. Flagellates can remain in the surface waters, whereas diatoms sink so that the heterogeneity is vertical as well as horizontal''. Vor allem genauere biochemische Informationen sind aber erforderlich, um diese Zusammenhange voll zu analysieren.