The Upper Tisa Valley. Preparatory proposal for Ramsay

from the Carpathian Biosphere Reserve Herbarium in Rahiv (Ukraina). In the species
enumeration, we indicated for each plants the river section at which the plant grows,
the work that quotes it, the bio-form (lifeform), the floristic element and the
cenotaxons in which it occurs. In the presentation of the hydrophilous, hygrophilous
and hygro-mesophilous vegetal associations only the river sections in which the
cenotaxon is spread is specified. The categorisation of bio-forms (life forms), floristic
elements and the classification of the plant associations are done following V. Sanda et
al. (1980, 1983), R. Soó (1964-1980), D. Dubyna et al. (1993) and our observations.
On geomorphological-climatic and national basis we divided the Upper Tisa
section into six sections: the Chorna Tisa (CT), the Bila Tisa (BT), the united
mountainous section of River Tisa (MT), the joined Romanian-Ukrainian section of
River Tisa (JT), the hilly Ukrainian section of River Tisa (UT) and the Hungarian
Upper Tisa section (HT).
Rivers Chorna and Bila Tisa are the alpine-subalpine-mountainous river
sections extending between 2061 m a.s.l. (above Baltic sea level) and 450-500 m a.s.l.
(the confluence of the two branches is upstream from Rahiv). Yearly average
temperature is between 0 °C and 5 °C, and yearly average precipitation is between
1000 - 1400 mm.
The united mountainous section of River Tisa represents the section between
the confluence of rivers Chorna and Bila Tisa and the locality of Dilove (about 350 m
a.s.l.) at the Romanian-Ukrainian border. Annual mean temperature is around 5 °C - 6
°C and yearly precipitation is around 800 -1000 mm.
In the joined Romanian-Ukrainian section of River Tisa, from Dilove to
Tyachiv (about 210 m a.s.l.) yearly mean temperature is 6 °C - 7 °C, and yearly
precipitation is 700 -900 mm.
In the hilly Ukrainian section of River Tisa, between Tyachiv and Vylok (about
120 m a.s.l.), annual mean temperature is 7 °C - 9 °C and annual precipitation
diminishes to 600 - 700 mm.
In the Hungarian Upper Tisa section, from Vylok to the confluence with the
River Szamos (about 100 m a.s.l.) annual average temperature is 9 °C - 10 °C, and
precipitation is around 600 mm/year.
Under these climatic conditions both flora and vegetation have a more and
more thermophilous and xerophilous character from River Tisa’s springs towards its
confluence with River Szamos.
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