Metody badania produkcji pierwotnej w ekosystemach słodkowodnych

Streszczenie w języku angielskim

Pages 123-138 ; 24 cm

Bibliographical references (pages 135-137)

A discussion is given different methods of examining the primary production of associations in inland waters, taking into consideration plankton, periphyton, macrophytes and mixed associations. The following groups of methods were distinguished:1) Analysis of increases in the biomass of producers and calculation of actual production based on known or assumed characteristics of the association of producers.a) calculation of production from biomass and turnover;b) ca1culation of production from measurements of increase in biomass in time (one particular case in this group of methods is calculation of the production of macrophytes on the basis of maximum yearly biomass).2) Analysis of environmental changes taking place under the influence of photosynthesis processes and calculation on this basis of the photosynthesis value.a) measurements of variations in the amount of oxygen in an environment;b) measurements of variations in the amount of carbon dioxide direct analyses by chemical or physical methods and indirect analyses of variations in the amount of C02 reflected in variations in pH or conductivity);c) measurements of variations in the amounts of certain biogens.3) Analysis of the amount of carbon assimilated by plants during the process of photosynthesis (method of calculation of primary production using 14C).4) Analysis in indices of producers biomass and ca1culation of their production on the basis of a knowledge of factors limiting this production (e.g. calculation of production on the basis of information of the amount of chlorophyll and amount of solar energy per unit of surface of the water body).The paper discusses in greater detail several methods chosen from the point of view of the possibility of their application on a wider scale in the investigations carried out in Poland under the International Biological Programme. For mass comparati1e studies in eutrophic environments the application of the oxygen method of light and dark bottles for plankton and periphyton was proposed (in the case periphyton the necessity of analysing the amount of substrate suitable for colonisation was emphasised) and methods of investigating production on the basis of estimation of maximum biomass in the case of macrophytes.In discussing the oxygen method atention was drawn to the possible sources of error limiting the range of its application and stress laid on the necessity for a large number of repeats to eliminate non-directional deviations (accidental deviations) caused by the lack of uniformity of the material.

Abstract in English

Strony 123-138 ; 24 cm

Bibliografia na stronach 135-137