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Environmental Fluid Mechanics - The paper addresses the influence of intense sediment transport (bed load and debris flow) on the efficiency of the structures aimed at the interception of wood... 相似文献
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Assessment of the effects of soil PAH accumulation by a battery of ecotoxicological tests 总被引:2,自引:0,他引:2
Surface soils were collected at remote, urban and industrial sites in the Southern of Italy in order to evaluate PAH concentrations and assess the toxic effects by a battery of ecotoxicological tests. The tests were performed on whole soils and on both organic and aqueous extracts. Further goal of this study was to integrate the results coming from each test and matrix in a synthetic toxicity index. The highest summation sigmaPAH concentrations were measured at the industrial soil, although this one did not show an high ecotoxicological risk. Among the performed tests, the phytotoxicity tests showed the highest sensitivity. For whole soil, the worst case always has been represented by test through bacteria. Our results could represent the first step toward the selection of a proper battery to characterize the soil ecotoxicological risk. 相似文献
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Sebastiano?SalvidioEmail author Giulia?Palumbi Antonio?Romano Andrea?Costa 《Die Naturwissenschaften》2017,104(3-4):20
Recent studies suggest that many organisms actively colonize the subterranean environment to avoid climatic stress, exploit new ecological opportunities and reduce competition and predation. Terrestrial salamanders are known to colonize the more stable subterranean habitats mainly to escape external climatic extremes, while the role of predation avoidance remains untested. To better understand the importance of predation, we used clay models of the cave salamander Speleomantes strinatii to compare the predation occurring in woodland and subterranean habitats. Models were positioned in three forests and in three caves in NW Italy. One-hundred eighty-four models were retrieved from the field and 59 (32%) were attacked by predators. Models were attacked on their head more often than expected by chance and, therefore, were perceived by predators as real prey items. In the woodlands, clay models showed a four-time higher probability of being attacked in comparison to caves, suggesting a different level of potential predation risk in these surface habitats. These findings are one of the first experimental evidences that, in terrestrial ecosystems, predation avoidance may contribute to the salamander underground colonization process. 相似文献
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Giulia Atzori Violetta Aru Flaminia Cesare Marincola Laura Chiarantini Daniela Medas Giorgia Sarais 《Chemistry and Ecology》2018,34(8):727-746
Coastal lagoons are subject to several sources of contaminations. To shade light on the contamination level of the Santa Gilla lagoon (Tyrrhenian Sea) we investigated the spatial distribution of Cr, Ni, Pb, Zn and Hg in sediments and their correlation with grain size and organic matter contents. Moreover, sediment contamination levels and the ecological risk associated with metal concentration were assessed using different abiotic indicators. The lagoon is characterised by low levels of contamination, with exceptions for Pb and Hg, whose distribution reflects the position of an old chlor-alkali plant and that of an airport. These results indicate that the restoration put in place 30 years ago have not reached the expected target and that the presence of the airport deserves further attention. In the outer section of the lagoon, where clam fishery occurs, we observed low levels of contamination suggesting that such artisanal fishery could somehow help mobilising metals. We conclude that the area exposed to Hg pollution, though tentatively restored, still suffers of a potential risk of ecosystem deterioration. We pinpoint that further investigations on the mobility, bioavailability and toxicity of metals are needed to finally address the actual impairment of the Santa Gilla lagoon. 相似文献
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Sergio Castellano Valentina Marconi Valeria Zanollo Giulia Berto 《Behavioral ecology and sociobiology》2009,63(8):1109-1118
As in many lekking anurans, Italian treefrog males use two mating tactics: they can attract females by calling vigorously
or be satellites, that is, they can remain silent in proximity of a calling male and try to intercept females attracted by
their neighbour. We investigated the factors that affected the expression of this mating tactic. Consistent with the conditional
mating tactic hypothesis, satellites were smaller than average and smaller than their parasitised calling males. They spent
a larger-than-average number of nights at the breeding site, where most of them were also observed calling. Moreover, satellites
showed lower call rates and lower mating success than those of males they parasitise but not lower than those of males they
did not parasitise. Overall, these results, together with those derived from the analyses of the seasonal and spatial distribution
of males, provide evidence for a non-random association between satellites and calling males and are consistent with the hypothesis
that satellites have spectral and temporal acoustic preferences that parallel those of females. By adopting the less-successful
satellite mating tactic, competitively inferior males can nevertheless maximise their potential reproductive fitness by sexually
parasitising the most attractive chorusing males. 相似文献
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The delineation of bioclimatic areas is a key tool in informing sustainable land management strategies, especially in the light of climate change. It requires an in-depth analysis of climate data but also of the physical and biological factors that affect the distribution of natural vegetation. The present study applies an exploratory data analysis aimed at defining bioclimatic conditions in an area characterized by steep slopes and prone to soil erosion (Amalfi Coast, southern Italy). To this end, we analyzed long-term (1959–1999) monthly rainfall and temperature data measured at 28 gauging stations within the study area using a geographic information system and multivariate statistical tools. Then, we analyzed how the spatial distribution of rainfall and temperature data relates to topography, vegetation cover, and soil erosion. We also derived bioclimatic indicators from the geostatistical analysis. We then identify and comment on drawbacks found in the procedure used in the present study, discussing possible solutions to overcome such problems. We finally discuss the potential contribution of this study to the development of sustainable land management policies for socio-ecological systems with complex topography. 相似文献
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M. D. Vazquez-Illanes R. Barcia I. Ibarguren J. A. Villamarín J. I. Ramos-Martínez 《Marine Biology》1992,112(2):277-281
6-phosphofructo-2-kinase (PFK-2) from the mantle of the sea musselMytilus galloprovincialis Lmk, collected from the Ría de Arosa (NW Spain) in 1990, was purified 550-fold by extraction and sequential affinity chromatography on Affi-gel Blue and ATP-agarose columns. The enzyme was a dimer with a native molecular weight of 100 kilodaltons (KDa) and a subunitM
r of 53 KDa. PFK-2 activity is dependent on the presence of Pi. At physiological Pi concentrations, the enzyme exhibits hyperbolic kinetics with both ATP and Fru-6-P, withK
m values of 0.62 and 0.37 mM respectively. In vivo, PFK-2 activity is limited by the concentration of Fru-6-P which is low in comparison with theK
m for this substrate. Citrate and PEP inhibited PFK-2 activity. 相似文献