Search results for "weed"
showing 10 items of 321 documents
A survey of the weedy communities of Sicily
2007
As Sicily has been a central crossroads of human activity for thousands of years, it offers a major perspective on the Mediterranean weedy plant communities. This syntaxonomical survey of the Sicilian weedy vegetation groups together for the first time 30 plant associations, that have been described from the main and neighboring island in the last three decades. The surveyed vegetation is ascribed to the classes Papaveretea rhoeadis and Stellarietea mediae, whose floristic autonomy is here discussed, and to the orders Aperetalia spicae-venti and Papaveretalia rhoeadis for the former, Polygono-Chenopodietalia polispermi, Solano-Polygonetalia convolvuli, Thero-Brometalia and Urtico-Scrophular…
Macroalgae transplant to detect the occurrence of anthropogenic nutrients in seawater of highly tourist beaches in Mediterranean islands
2020
In the Mediterranean region, islands are among the most important tourist destinations, being sites of considerable naturalistic, historical and cultural importance. This is highly beneficial for local economies, but may also represent a threat for the environment, especially during the peak season (i.e. summer). Indeed, the sharp demographic increase concentrated in a relatively short period may negatively affect the quality of coastal marine systems and the provision of ecosystem services, producing in turn negative feedbacks on tourism industry. Nevertheless, the assessment of the environmental impact of tourism on coastal seawater has been seldom addressed. Here, we show the results of …
Food selection of a generalist herbivore exposed to native and alien seaweeds
2018
Understanding which factors influence the invasion of alien seaweed has become a central concern in ecology. Increasing evidence suggests that the feeding preferences of native herbivores influence the success of alien seaweeds in the new community. We investigated food selection of a generalist native grazer Paracentrotus lividus, in the presence of two alien seaweeds (Caulerpa cylindracea and Caulerpa taxifolia var. distichophylla) and two native seaweeds (Dictyopteris membranacea and Cystoseira compressa). Sea urchins were fed with six experimental food items: C. cylindracea, C. taxifolia var. distichophylla, a mixture of C. cylindracea and C. taxifolia var. distichophylla, D. membranace…
The Stagnone of Marsala lagoon
2009
The Stagnone of Marsala is an oligotrophic lagoon situated on the western coast of Sicily. The area has been under study since the mid-nineteenth century. Research has focused on its physiographic, chemical-physical, biological, ecological features and, particularly, on submerged vegetation. Its main biotic component, a meadow of Posidonia oceanica, is distributed among peculiar reef formations inside and outside the lagoon, which are extremely interesting from an ecological and environmental point of view. The seagrass grows near to its thermal and salinity tolerance level in the inner lagoon, where it is partially replaced by Cymodocea nodosa and Caulerpa prolifera meadows. Algal assembla…
Ocean acidification bends the mermaid's wineglass
2015
Ocean acidification lowers the saturation state of calcium carbonate, decreasing net calcification and compromising the skeletons of organisms such as corals, molluscs and algae. These calcified structures can protect organisms from predation and improve access to light, nutrients and dispersive currents. While some species (such as urchins, corals and mussels) survive with decreased calcification, they can suffer from inferior mechanical performance. Here, we used cantilever beam theory to test the hypothesis that decreased calcification would impair the mechanical performance of the green alga Acetabularia acetabulum along a CO 2 gradient created by volcanic seeps off Vulcano, Italy. Cal…
Inorganic carbon physiology underpins macroalgal responses to elevated CO2
2017
Beneficial effects of CO2 on photosynthetic organisms will be a key driver of ecosystem change under ocean acidification. Predicting the responses of macroalgal species to ocean acidification is complex, but we demonstrate that the response of assemblages to elevated CO2 are correlated with inorganic carbon physiology. We assessed abundance patterns and a proxy for CO2:HCO3− use (δ13C values) of macroalgae along a gradient of CO2 at a volcanic seep, and examined how shifts in species abundance at other Mediterranean seeps are related to macroalgal inorganic carbon physiology. Five macroalgal species capable of using both HCO3− and CO2 had greater CO2 use as concentrations increased. These s…
Uptake and photoinduced degradation of phthalic acid esters (PAEs) in Ulva lactuca highlight its potential application in environmental bioremediation
2022
Abstract The bioaccumulation of phthalates was studied in fragments of Ulva lactuca exposed for a maximum of 31 days at different concentrations of a solution of six phthalic acid esters (PAEs). The algal matrix showed rapid uptake since the first sampling, which increased over the time of the experimental period, at the end of which seaweed’s bioaccumulation potential was also evaluated. After the uptake, the algal matrix was subjected to UV irradiation in order to verify the removal of the phthalates. PAEs with higher octanol–water partition coefficients (logKow) and molecular weights were preferentially uptaken by U. lactuca in all the exposure experiments. It was observed that both accu…
Food Sources for Benthic Grazers in Trophic Networks of Macrophyte Habitats in a Transitional Baltic Ecosystem
2022
In this study, we provide insights into that characteristics of two sites representing different conditions of productivity and salinity impact on trophic network structures of macrophyte habitats and diet of benthic grazers at the active vegetation period in the Curonian Lagoon (southeastern Baltic Sea). Regarding the epiphytic growth, macrophytes were more overgrown in the relatively less productive (northern) site with a muddy bottom and more frequent marine water inflow than in the (southern) site with higher productivity and freshwater sandy habitat. Stable isotope analysis revealed that organisms’ samples from the northern site were more enriched with the heavier carbon isotopes, but …
Influence of Ecklonia maxima Extracts on Growth, Yield, and Postharvest Quality of Hydroponic Leaf Lettuce
2021
Ecklonia maxima is a brown algae seaweed largely harvested over the last years and used to produce alginate, animal feed, fertilizers, and plant biostimulants. Their extracts are commercially available in various forms and have been applied to many crops for their growth-promoting effects which may vary according to the treated species and doses applied. The aim of the study was to characterize the effect of adding an Ecklonia maxima commercial extract (Basfoliar Kelp
Bioaccessibility of inorganic arsenic species in raw and cookedHizikia fusiformeseaweed
2004
Samples of Hizikia fusiforme edible seaweed, a commercially available dried food with high concentrations of total arsenic (t-As) and inorganic arsenic (i-As), both raw and cooked (boiling at 100 °C, 20 min), were selected for the bioaccessibility study. Cooking caused a significant reduction in the concentrations of t-As (30–43%) and i-As (46–50%), despite which the i-As contents in the cooked product were high (42.7–44.6 µg g−1 seaweed). An in vitro gastrointestinal digestion (pepsin, pH 2, and pancreatin–bile extract, pH 7) was applied to the seaweed to estimate arsenic bioaccessibility (maximum soluble concentration in gastrointestinal medium) of t-As, i-As, arsenic(III) and arsenic(V).…