Full resolution (JPEG) - On this page / på denna sida - I. Physical Geography. Introd. by [G. Sundbärg] Gunnar Andersson - 5. Flora. By H. Hesselman
<< prev. page << föreg. sida << >> nästa sida >> next page >>
Below is the raw OCR text
from the above scanned image.
Do you see an error? Proofread the page now!
Här nedan syns maskintolkade texten från faksimilbilden ovan.
Ser du något fel? Korrekturläs sidan nu!
This page has never been proofread. / Denna sida har aldrig korrekturlästs.
FLORA.
(71
Specially characteristic of the northern coniferous forest is the great
stock of species of Sparganium with long narrow floating leaves which
cover broad areas of water. The lake-vegetation is most luxuriant where
the bottom is composed of clay — as a rule, therefore, below the
highest marine limit; while lakes with a bottom of gravel or sand have
a vegetation which, though rich in species, is quite sparse. On the whole,
the water-plant flora diminishes towards the north in both luxuriance
and number of species; and the lakes of the Alpine region almost entirely
lack flowering plants.
Photo. Hf.xrik Hesselman.
A Forest Tarn.
Owing lo the fact that the dead and decaying plant-remains become
piled up in the water, many lakes are gradually filled up, and the
vegetation from the shores pushes further and further into the water-area,
which may at last entirely disappear. The dead-plant remains form
peat, and in this way many moors in Sweden have come into existence.
From such centres moors may gradually spread out over the surrounding
country and so enlarge their domain. In the northern region of
coniferous forests moors have often been formed on sloping but
waterlogged ground; and such "hillside bogs" have attained a considerable
extent and are characteristic of that part of the country. The
formation of moors is favoured by a climate with a low temperature, which pre-
<< prev. page << föreg. sida << >> nästa sida >> next page >>
