Effects of Natural and Anthropogenic Stressors on Fucalean Brown Seaweeds Across Different Spatial Scales in the Mediterranean Sea

Algal habitat-forming forests composed of fucalean brown seaweeds (Cystoseira, Ericaria, and Gongolaria) have severely declined along the Mediterranean coasts, endangering the maintenance of essential ecosystem services. Numerous factors determine the loss of these assemblages and operate at different spatial scales, which must be identified to plan conservation and restoration actions. To explore the critical stressors (natural and anthropogenic) that may cause habitat degradation, we investigated (a) the patterns of variability of fucalean forests in percentage cover (abundance) at three spatial scales (location, forest, transect) by visual estimates and or photographic sampling to identify relevant spatial scales of variation, (b) the correlation between semi-quantitative anthropogenic stressors, individually or cumulatively (MA-LUSI index), including natural stressors (confinement, sea urchin grazing), and percentage cover of functional groups (perennial, semi-perennial) at forest spatial scale. The results showed that impacts from mariculture and urbanization seem to be the main stressors affecting habitat-forming species. In particular, while mariculture, urbanization, and cumulative anthropogenic stress negatively correlated with the percentage cover of perennial fucalean species, the same stressors were positively correlated with the percentage cover of the semi-perennial Cystoseira compressa and C. compressa subsp. pustulata. Our results indicate that human impacts can determine spatial patterns in these fragmented and heterogeneous marine habitats, thus stressing the need of carefully considering scale-dependent ecological processes to support conservation and restoration

Bioecological study of the benthic communities on the soft bottom of the Vlora Gulf (Albania)

Data on the soft bottom benthic communities of the Vlora Gulf along the Albanian coast were collected in the context of the international Centro Internazionale di Scienze del Mare (CISM) project funded by the Apulian region. The present study investigated and mapped the different communities inside the Gulf of Vlora, Albania, which are continuously affected by various natural and anthropogenic sources. Two research cruises were carried out in the Vlora Gulf during May 2007 and January 2008. During the first exploratory survey, the depth and morphology of the soft bottom was identified with a multibeam echo sounder and the Side-Scan–Sonar system; a preliminary map of the biocoenosis was created and a sampling plan was defined. In the second survey, 58 sampling stations were established in the study area using Van Veen grabs and scuba dives. A total of 151 taxa were identified (1 Foraminifera, 6 Cnidaria, 3 Nemertea, 2 Sipuncula, 36 Mollusca, 53 Annelida, 25 Crustacea Decapoda, 7 Bryozoa, 15 Echinodermata, 1 Hemichordata, and 2 Tunicata); 54 species were reported for the first time in Albania. The analyses showed there were three main habitats in the investigated area: the biocoenosis of terrigenous mud; a wide, muddy matte of Posidonia oceanica; and the narrow residual areas of P. oceanica meadows. The present study represents the first experience in mapping the benthic biocoenosis of the Vlora Gulf of Albania and shows a progressive decay of the benthic communities in the area, especially if compared with the previous few studies

Charophytes (Charales) of lake Skadar/Shkodra: Ecology and distribution

Charophytes or stoneworts (Charales, Characeae) are submerged green macroscopic algae of great importance for the environmental and economic sustainability of the aquatic ecosystem of Lake Skadar/Shkodra. In the course of many years of research of these algae in the Montenegrin and the Albanian part of Lake Skadar/Shkodra, 30 taxa of charophytes have been registered in the rank of species, forms and varieties. These taxa belong to the four genera of the Characeae family existing in the lake – namely, Chara, Nitella, Tolypella and Nitellopsis. The largest number of taxa belongs to the genus Chara, namely, 12 species, 3 forms and 2 varieties, 10 species belong to the genus Nitella, 2 species belong to the genus Tolypella and, finally, only 1 species belongs to the genus Nitellopsis. The ecological and phytocenological characteristics of each taxon, as well as the hydrological and geomorphological characteristics of their finding sites, are presented in order to emphasize the fact that Lake Skadar/Shkodra is one of the most significant charophyte diversity centres in the Balkan Peninsula. All the data presented in this study are based on our own field investigations, as well as herbarium and literature surveys

Effects of natural and anthropogenic stressors on fucalean brown seaweeds across different spatial scales in the Mediterranean Sea

Algal habitat-forming forests composed of fucalean brown seaweeds (Cystoseira, Ericaria, and Gongolaria) have severely declined along the Mediterranean coasts, endangering the maintenance of essential ecosystem services. Numerous factors determine the loss of these assemblages and operate at different spatial scales, which must be identified to plan conservation and restoration actions. To explore the critical stressors (natural and anthropogenic) that may cause habitat degradation, we investigated (a) the patterns of variability of fucalean forests in percentage cover (abundance) at three spatial scales (location, forest, transect) by visual estimates and or photographic sampling to identify relevant spatial scales of variation, (b) the correlation between semi-quantitative anthropogenic stressors, individually or cumulatively (MA-LUSI index), including natural stressors (confinement, sea urchin grazing), and percentage cover of functional groups (perennial, semi-perennial) at forest spatial scale. The results showed that impacts from mariculture and urbanization seem to be the main stressors affecting habitat-forming species. In particular, while mariculture, urbanization, and cumulative anthropogenic stress negatively correlated with the percentage cover of perennial fucalean species, the same stressors were positively correlated with the percentage cover of the semi- erennial Cystoseira compressa and C. compressa subsp. pustulata. Our results indicate that human impacts can determine spatial patterns in these fragmented and heterogeneous marine habitats, thus stressing the need of carefully considering scale-dependent ecological processes to support conservation and restoration