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luteum, calculated as the sum of all enrichment factors of the elements determined.
Evaluating data with regard to the limits of variability - as referred to the minimal and
maximal values - an astonishingly small variation is found in spite of the many
influencing factors. On that account it is to be concluded that the enrichment of minor
elements in water plants is a useful criterion to calculate the average concentration of
these elements in water. By means of a relatively small number of samples it is already
possible to assess the trend of water pollution by metals.
Starting from the principle that the statistically confirmed proportion rates are still
valid if the concentration of the minor elements in the waters is below the analytical
detection limit, so the microanalysis of the plants will yield useful results in the
calculation of the concentration in water, making use of enrichment factors. The data,
however, give no information as to which concentration of the minor elements in the
water the simple proportionality is valid, and there is also no information about the
limiting concentration for the development of these plants in their ecological system of
water.
It is intended to extend this test program to other trace elements such as
molybdenum, cobalt, vanadium, tungsten and boron.
It may be desirable for similar investigations to be carried out in other local systems to
compare the results in order to obtain confirmation of these findings.