Die Beeinflussung der Translokationen organischer Stoffe in den wachsenden Trieb durch feste Immissionen bei Koniferen

Wien

1972

S. 419-430

5 Abb.

Unselbständiges Werk

200144615

The effect of solid pollutants may not always be direct. Organs like young shoots, flowers and fruits for example, which rely on the translocation of assimilates from the places where they are produced, are not only injured directly by the pollutants but are also affected indirectly by inhibition of translocation of assimilates. The organs supplying the assimilates, which in evergreen broadleaved species and conifers are the photosynthetically active leaves and needles of the previous years, exhibit a reduced rate of photosynthesis due to dust; they are also exhausted by removal of increased amounts of organic products and fall earlier than normal, even in the absence of toxic elements in the pollution. We have already proved the increased exhaustion of old dust-coated leaves of evergreen broadleaved species by translocation of assimilates during the spring extension growth, and we also repeated the experiment on conifers (Abies grandis). In the spring of the current year, we determined the exhaustion of the previous year's dust-coated and non-dusty needles of Pinus nigra, by means of the modified half-leaf method of Sachs and the modified method of Ivanov and Kossovich.