Search results for " Ecologia"

Using natural analogues to investigate the effects of climate change and ocean acidification on Northern ecosystems

2018

AbstractNorthern oceans are in a state of rapid transition. Still, our knowledge of the likely effects of climate change and ocean acidification on key species in the food web, functionally important habitats and the structure of Arctic and sub-Arctic ecosystems is limited and based mainly on short-term laboratory studies on single species. This review discusses how tropical and temperate natural analogues of carbonate chemistry drivers, such as CO2 vents, have been used to further our knowledge of the sensitivity of biological systems to predicted climate change, and thus assess the capacity of different species to show long-term acclimation and adaptation to elevated levels of pCO2. Natur…

Elogio delle vagabonde. Erbe, arbusti e fiori alla conquista del mondo.

2010

All Colors of the World. L’antropologia della Terra nelle Bandiere Satellitari di Serradifalco

2017

L’articolo propone una riflessione sulla visione apolitica e quasi utopica permessa oggi dai satelliti e dalle piattaforme Google Maps e Google Earth. Grazie a questo tipo di prospettiva nascono le Bandiere Satellitari di Max Serradifalco "All Colors of the World". Queste opere educano chi le osserva a un’ecologia della cultura, a una vera e propria Antropologia della Terra. La serie di immagini permette una prospettiva antropologica attuale e uno storytelling potente e innovativo sulla rappresentazione stessa della Terra, e sui concetti di spazio, confine, condivisione, diritto, identità, uguaglianza, differenza. Con le sue bandiere-puzzle che esprimono identità politica fatta al contempo …

Trophic Transfer of Trace Elements in an Isotopically Constructed Food Chain From a Semi-enclosed Marine Coastal Area (Stagnone di Marsala, Sicily, M…

2012

Trace element accumulation is particularly important in coastal and transitional environments, which act as contaminant buffers between the continental and marine systems. We compared trace element transfer to the biota in two locations with different open-sea exposures in a semi-enclosed marine coastal area (Stagnone di Marsala, Sicily, Italy) using isotopically reconstructed food chains. Samples of sediment, macroalgae, seagrasses, invertebrates, fish, and bird feathers were sampled in July 2006 and analysed for stable carbon and nitrogen isotopes (δ(13)C, δ(15)N) and trace elements (arsenic [As], cadmium [Cd], total mercury [THg], and lead [Pb]). Trophic magnification factors were calcul…

Fine-grain beta diversity in Palaearctic open vegetation: variability within and between biomes and vegetation types

2021

Aims: To quantify how fine-grain (within-plot) beta diversity differs among biomes and vegetation types. Study area: Palaearctic biogeographic realm. Methods: We extracted 4,654 nested-plot series with at least four different grain sizes between 0.0001 m² and 1,024 m² from the GrassPlot database spanning broad geographic and ecological gradients. Next, we calculated the slope parameter (z-value) of the power-law species–area relationship (SAR) to use as a measure of multiplicative beta diversity. We did this separately for vascular plants, bryophytes and lichens and for the three groups combined (complete vegetation). We then tested whether z-values differed between biomes, ecological-physi…

The importance of dead seagrass (Posidonia oceanica)matte as a biogeochemical sink

2022

We assessed the potential of dead seagrass Posidonia oceanica matte to act as a biogeochemical sink and provide a coherent archive of environmental change in a degraded area of the Mediterranean Sea (Augusta Bay, Italy). Change in sediment properties (dry bulk density, grain size), concentration of elements (Corg, Cinorg, N, Hg) and stable isotope ratios (δ13C, δ 15N) with sediment depth were measured in dead P. oceanica matte and unvegetated (bare) sediments in the polluted area, and an adjacent P. oceanica meadow. Principal Component Analysis (PCA) revealed a clear clustering by habitat, which explained 72% of variability in our samples and was driven mainly by the accumulation of N and H…

Biogeochemical evaluation of historical sediment contamination in the Gulf of Palermo (NW Sicily): Analysis of pseudotrace elements and stable isotop…

2012

Abstract Sedimentary biogeochemical data from the Gulf of Palermo, which borders one of the major urban and industrial areas of the central Mediterranean, provide a decennial–centennial-scale record of the effects of human activity on this coastal environment. In this study we report trace elements (TE), C org /N tot ratios, δ 13 C org , and δ 15 N tot from dated ( 210 Pb) sediments collected in two coastal stations variably influenced by urban/fluvial loadings and illegal dumping and we compare them with published data for offshore sediments, in order to investigate at a large spatial scale the influence of on-land activities on sedimentary marine system. TE were generally low except for H…

The fouling community as an indicator of fish farming impact in Mediterranean

2007

Fouling species richness, abundance and composition and biomass were chosen as the descriptors of effect of fish farm organic enrichment. The study was carried out in September 2004 in the Gulf of Castellammare (South Tyrrhenian, Mediterranean). The fouling species were sampled from plastic buoys spaced throughout the study area both up- [UP] and down-stream [DOWN]. The results showed that fouling community responded to the chronic input of allochthonous organic matter experiencing local changes more or less significantly with regard to abundance, species composition and general community diversity. Upper fouling would work as a first filter naturally opposed by environment resistance assim…

Use of stable isotopes to investigate dispersal of waste from fish farm as a function of hydrodynamics.

2006

Stable isotopes were used to examine differential effects of fish farm waste on the water column and sediments. To achieve this objective, we chose 3 marine fish farms located along the coast of Sicily (Mediterranean Sea) as point-source disturbances, and a control area. The hypothesis that carbon and nitrogen isotope composition of particulate (POM) and sedimentary (SOM) organic matter varied with increasing distance (from cages to 1000 m) was tested at 3 levels of hydrodynam- ics: low (mean velocity of current (MVC) ~12 cm s -1 ), intermediate (MVC ~22 cm s -1 ), and high (MVC ~40 cm s -1 ). Different isotopic signals from allochthonous (fish waste) over natural (phytoplankton, terrigenou…

Role of peat organic matter on isotopic composition of most abundant benthic organisms in intertidal habitats of SW Iceland

2008

The transfer of peat organic matter (OM) from tidal pools of upper littoral to downstream rocky shores and its potential incorporation into marine biota were investigated using the stable isotope approach. Samplings were carried out in September 2004 in two SW Icelandic sites (Osar and Hvassahraun), where we selected (1) areas with shores where grass gently declined towards rocks and, on reaching the sea line, formed small tidal peat pools and (2) areas where grass and rocky shores were not contiguous, rather the grass lower limits were several hundreds of meters back from the shore. In both grass and no grass areas, in the intertidal zone, all benthic organisms and all potential OM sources…