We provided new data on topography, morphology and physical/chemical parameters (pH, T, NO2-, Ca2+, PO43-, NaCl) collected in several shore grykes along the Northwestern Istrian coast, between ...Savudrija and Zambratija. Six transects, eachcontaining four to five pools, have been surveyed. Three morphological zones have been identified along the selected profiles. Morphological features of the shore grykes along the western Istrian coast are, in fact, closely related to the local tide. High-level pools are affected by karstic processes, and the surface is usually smooth. At their bottom, terrigenous deposits, mainly terra rossa, occur. Seaward, bioerosion prevails and at the bottom of the grykes, sand and rounded pebbles have been found. Chemical/physical parameters suggest that grykes located at lower altitudes are affected by seawater factors, while pools located at increasing altitudes are affected mainly by rainfall and consequentially freshwater or saltwater remaining from rainfalls or storm events. Shore gryke genesis is strongly controlled by geological weakness, along whichthey develop. Their origin is in fact due to local tectonics, while their development is related to the active vertical tectonic subsidence of the study area. Pools located at higher altitudes are mainly affected by solution karst processes, but due to the tectonic downdrop of the area, when the grykes come in contact withsea, they are gradually shaped by marine processes.
Basso D., Rodondi G. and Bressan G. 2011. A re-description of Lithothamnion crispatum and the status of Lithothamnion superpositum (Rhodophyta, Corallinales). Phycologia 50: 144-155. DOI: ...10.2216/10-20.1
After re-examination of the original Hauck's collection, a buried, empty multiporate tetrasporangial conceptacle was detected in the lectotype material of Lithothamnion crispatum. The morphology and anatomy of the type material were compared to freshly collected representative plants from the Mediterranean. In L. crispatum, the five to seven rosette cells surrounding each pore of the tetra/bisporangial conceptacle roof are larger than the normal epithallial cells and undergo degeneration. As a consequence of the disintegration of the outermost cells in filaments surrounding the pore canals, the tetra/bisporangial conceptacle roofs appear pitted with depressions, each one hosting a pore and the surrounding rosette cells. A previous revision of the type material of Lithothamnion superpositum from South Africa showed this same tetra/bisporangial conceptacle roof structure and development, and corresponding vegetative and reproductive characters. These taxa are thus conspecific; therefore, L. superpositum is a younger heterotypic synonym of L. crispatum, the latter having nomenclatural priority. While the type specimen lacked gametangial plants, these are described for representative freshly collected material and found to be dioecious.
Issue Title: Theme Marine Biodiversity: Patterns and Processes, Assessment,Threats, Management and Conservation The practical assessment of the biogenic structural complexity poses some problems in ...non-symmetrical or three-dimensional macroalgae. This study represents the first attempt to measure quantitatively the phenology and the plasticity of Cystoseira barbata (Stackhouse) C. Agardh in the Mediterranean Sea. This canopy-forming brown alga is characterised by a ramified monopodial cauloid and a dendroid frond. To analyse the morphological-spatial changes in time and the plasticity of C. barbata an experiment was conducted in a protected sea area of the Northern Adriatic Sea on thalli taken from a natural population and a transplanted one, re-located in deeper water. The three-dimensional complexity of thalli and the frond architecture were analysed by means of quantitative structural (total area, perimeter) and spatial (intercepting area, volume and interstitial area) attributes. A preliminary assessment of the primary production of the basiphyite-epiphyte system was investigated by a volumetric analysis. The thalli showed a seasonal pattern characterised by a marked phenological variation of the fronds, both in size and in shape. The seasonal trend was comparable in the both populations studied, with fronds largest in spring-summer, whereas the fall of phylloids and branchelets occurs in autumn-winter. Also the abundance of algal epibionts on the host varied seasonably and depended mainly on the life-form of Cystoseira fronds, where complex fronds encouraged more abundant associated epibionts. The morphological variability of different individuals was also investigated using some bio-structural indices. These indices were proposed as useful for a more detailed description of the phenology of C. barbata and for a better evaluation of the potential micro-spatial and structural habitat available inside the fronds. The proposed protocol and the quantitative descriptors analysed may be employed in physiological or ecological studies, being useful for a standardisable classification of a habitat's complexity. The analysed spatial and structural attributes, as well as the definition of the complexity of C. barbata, enable the evaluation of the area available for the attachment and shelter of epibionts together with the number and type of potential habitats.PUBLICATION ABSTRACT
In this study, transplantation techniques for the macroalgae Cystoseira barbata (Stackhouse) C. Agardh and Cystoseira compressa (Esper) Gerloff & Nizamuddin were investigated to improve habitat ...enhancement procedures and to test their feasibility as a restoration tool.
Adult thalli were transplanted onto artificial modules in two locations in the Northern Adriatic Sea (Mediterranean Sea). Different techniques were employed for the two species. Growth and survival rates of the transplanted sporophytes were monitored monthly for 1 yr and compared with naturally
settled sporophytes. Based on the results of this study, the transplantation process for C. barbata seems to be successful, while that for C. compressa needs to be refined. Sporeling cultures for C. barbata were tested in the laboratory to provide nurseries for rearing
of young plants for transplantation.
UDC 551.4(497.5-16) Stefano Furlani, Davide Chersicla, Guido Bressan, Sara Biolchi & Franco Cucchi: Shore grykes along the western Istrian coast We provided new data on topography, morphology and ...physical/chemical parameters (pH, T, NO super( 2-), Ca super( 2+), PO super( 3-) sub( 4), NaCl super( 3-) sub( 4)) collected in several shore grykes along the Northwestern Istrian coast, between Savudrija and Zambratija. Six transects, each containing four to five pools, have been surveyed. Three morphological zones have been identified along the selected profiles. Morphological features of the shore grykes along the western Istrian coast are, in fact, closely related to the local tide. High-level pools are affected by karstic processes, and the surface is usually smooth. At their bottom, terrigenous deposits, mainly terra rossa, occur. Seaward, bioerosion prevails and at the bottom of the grykes, sand and rounded pebbles have been found. Chemical/physical parameters suggest that grykes located at lower altitudes are affected by seawater factors, while pools located at increasing altitudes are affected mainly by rainfall and consequentially freshwater or saltwater remaining from rainfalls or storm events. Shore gryke genesis is strongly controlled by geological weakness, along which they develop. Their origin is in fact due to local tectonics, while their development is related to the active vertical tectonic subsidence of the study area. Pools located at higher altitudes are mainly affected by solution karst processes, but due to the tectonic downdrop of the area, when the grykes come in contact with sea, they are gradually shaped by marine processes.
The Corallinales of the Aegean coasts of Turkey have been relatively little studied, from both the floristic and the ecological point of view. The Turkish coasts offer a wide variety of environmental ...conditions, and the present study identifies and characterizes not only the presence or absence of these species, but also assesses their value as bioindicators. Qualitative collection of Corallinales was performed at 14 sites in a bathymetric range from 2 to 5 m depth, where, at the same stations, the main environmental variables were recorded. The subsequent data analysis proceeds in the following three-phase procedure: i) identification of well-characterized sample groups with regards to the ecological factors mostly influencing their floristic composition; ii) identification of ecological species groups on the basis of their frequency in the sample groups; iii) ecological gradient analysis based on a reciprocal ordering method. From an ecological viewpoint, the bioindicator value of Corallinales was shown by the fuzzy c-means clustering data analyses. These species of Corallinales seems to be linked to two main environmental factors: salinity and temperature.
The practical assessment of the biogenic structural complexity poses some problems in non-symmetrical or three-dimensional macroalgae. This study represents the first attempt to measure ...quantitatively the phenology and the plasticity of Cystoseira barbata (Stackhouse) C. Agardh in the Mediterranean Sea. This canopy-forming brown alga is characterised by a ramified monopodial cauloid and a dendroid frond. To analyse the morphological-spatial changes in time and the plasticity of C. barbata an experiment was conducted in a protected sea area of the Northern Adriatic Sea on thalli taken from a natural population and a transplanted one, re-located in deeper water. The three-dimensional complexity of thalli and the frond architecture were analysed by means of quantitative structural (total area, perimeter) and spatial (intercepting area, volume and interstitial area) attributes. A preliminary assessment of the primary production of the basiphyite-epiphyte system was investigated by a volumetric analysis. The thalli showed a seasonal pattern characterised by a marked phenological variation of the fronds, both in size and in shape. The seasonal trend was comparable in the both populations studied, with fronds largest in spring—summer, whereas the fall of phylloids and branchelets occurs in autumn—winter. Also the abundance of algal epibionts on the host varied seasonably and depended mainly on the life-form of Cystoseira fronds, where complex fronds encouraged more abundant associated epibionts. The morphological variability of different individuals was also investigated using some bio-structural indices. These indices were proposed as useful for a more detailed description of the phenology of C. barbata and for a better evaluation of the potential micro-spatial and structural habitat available inside the fronds. The proposed protocol and the quantitative descriptors analysed may be employed in physiological or ecological studies, being useful for a standardisable classification of a habitat’s complexity. The analysed spatial and structural attributes, as well as the definition of the complexity of C. barbata, enable the evaluation of the area available for the attachment and shelter of epibionts together with the number and type of potential habitats.
This work aims to examine the influence of various ecological parameters on periphyton colonization of artificial substrata by using multivariate analysis methods. The artificial substrata studied ...were the horizontal sides of a model of an artificial reef. This had been immersed at
a depth of 11 m on a muddy sandy bottom, near the Marine Biology Laboratory (Trieste), since May 1988. To record periphyton colonization by phytosociological monthly sampling, the surfaces examined were subdivided into 44 squares of 20 × 20 cm. Temperature and salinity data were recorded
twice a month by means of a computerized core-drill; sea water transparency by means of a Secchi disc. The ecological relationships, highlighted by multivariate analysis, among processes of colonization and physical parameter showed that the difference between surface-bottom temperature (thermocline)
together with reduction in transparency acted synergically and interfered with the development processes of the periphyton.
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