The Northern Adriatic Sea
Undisturbed site
Catenella caespitata
Fucus virsoides
Ulothrix spp.
Ceramium diaphanum
Polysiphonia spp.
HWL
LWL
Cystoseira compressa
Cystoseira barbata
Cystoseira crinita
C. corniculata
C. ercegovichii
crustose corallines ~ ~ ~ ~ : : .
Peyssonnelia spp. :::::. ,
Zonardinia prototyp'~.~.: ~:
379
Fig. 16.3. Scheme of zonation pattern at an undisturbed site; HWL high water level; L WL
low water level
association, 'decreased biomass, changed zonation patterns, uplift of the
lower limit of the vegetation and decreased floristic diversity. Sensitive
species, first of all several red algae, disappeared and some declined in
quantity. Species with a wide ecological valence are able to prosper in
eutrophicated biotopes and replace the previous Fucacean stands and red
algal belts.
Even in relatively undisturbed sites, distant from the outfalls of sewage
(Fig.16.4) several changes became obvious, first of all the admixture of
nitrophilous species into the Fucacean populations. The Fucus virsoides
stands were less dense and considerable amounts of Ulva rigida and
Enteromorpha species were obvious in both, the eulittoral and upper
sublittoral. The intermediate red algal belt was reduced or absent. Populations of Dictyota dichotoma and Halopteris scoparia (Stypocaulon
Undisturbed site
Catenella caespitata
Fucus virsoides
Ulothrix spp.
Ceramium diaphanum
Polysiphonia spp.
HWL
LWL
Cystoseira compressa
Cystoseira barbata
Cystoseira crinita
C. corniculata
C. ercegovichii
crustose corallines ~ ~ ~ ~ : : .
Peyssonnelia spp. :::::. ,
Zonardinia prototyp'~.~.: ~:
379
Fig. 16.3. Scheme of zonation pattern at an undisturbed site; HWL high water level; L WL
low water level
association, 'decreased biomass, changed zonation patterns, uplift of the
lower limit of the vegetation and decreased floristic diversity. Sensitive
species, first of all several red algae, disappeared and some declined in
quantity. Species with a wide ecological valence are able to prosper in
eutrophicated biotopes and replace the previous Fucacean stands and red
algal belts.
Even in relatively undisturbed sites, distant from the outfalls of sewage
(Fig.16.4) several changes became obvious, first of all the admixture of
nitrophilous species into the Fucacean populations. The Fucus virsoides
stands were less dense and considerable amounts of Ulva rigida and
Enteromorpha species were obvious in both, the eulittoral and upper
sublittoral. The intermediate red algal belt was reduced or absent. Populations of Dictyota dichotoma and Halopteris scoparia (Stypocaulon