Beschreibung: In der folgenden Besprechung veröffentlichter Beobachtungen wird betont, daß die chemischen und autökologischen Methoden in der Produktionsbiologie einander ergänzen müssen. Am Beispiel der Frühjahrsblüte des Phytoplanktons wird darauf hingewiesen, daß bessere Kenntnisse der Umweltansprüche der dominanten Algen ein besseres Verständnis des Eintritts der Blüte ermöglichen würden. Eine Planktongerneinschaft kann wegen des Wechsels der Größe der Organismen nicht durch Individuenzahlen von Arten allein charakterisiert werden; die in Organismen gebundene Biomasse muß durch mikroskopische Messung abgeschätzt werden. Allerdings gibt erst die chemische Bestimmung die Gesamtmenge des suspendierten Eiweißes oder der suspendierten Substanz.

Beschreibung: The aim of the present investigation in the southern parts of the North Sea during March 1955 has been to get an idea of the standing crop of plankton by serial analysis which were completed within a few days. The observations are given in the plates 14 to r 7 which show the distribution of turbidity, weight of particulate matter, albumine and chlorophyll. Caused by the long winter the amounts of the two latter components are very low. The water columns being vertically homogenous in most parts of the area of investigation, the results may hold right from the surface to the sea bed. For the southeastern part of the North Sea it is shown that, at least after lang winters, the cletritus contenting chlorophyll may be desintegrated; in that case the amount of phytoplankton can be calculated from the chlorophyll observations, as has been clone in table 3 p. 173, where with the aid of the albumine values the composition of the suspended matter is approximated. In all areas investigated, either in turbicl or clear water, the content of "plankton" (including bacteria and fresh detritus) in the total suspended matter never exceeds 10%. For the named southeastern part of the North Sea in the end of March 1955 the dry weight of "plankton" is calculated as 1,4 g/m2 dry ash-free organic matter, assuming a mean depth of 40 m. This value corresponds to 0,6-0,7 g/m2 Carbon which is thought to be the minimum standing crop for the southern North Sea in winter. In an appendix some comments are given on the ratio chlorophyll / organic matter and similar relationships.

Beschreibung: A literature survey of oceanographic observations off the east coast of India is presented. For Waltair it is suggested that during fall the tendency for sinking is counterbalanced by the salinity stratification. Strong vertical mixing depresses the surface concentration of oxygen heavily. Nutrients are brought up at the same time as indicated by phytoplankton blooms. The river discharge during southwest monsoon does not contribute important amount of phosphate phosphorus to the sea. - Markedly seasonal blooms of phytoplankton are not observed off Madras as there is no marked seasonal upwelling. - Other areas in the northern Bay of Bengal are mentioned.