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A new method to study microtopographical changes in the intertidal zone: one year of TMEM measuremets on a limestone removable rock slab (RRS).
No full textA new approach to the problem of measuring microtopographical changes on vertical limestones in the intertidal zone, simple and cost-effective, is discussed. It is based on the positioning of a rock removable slab (RRS) in the intertidal zone. The RRS method allows to use the traversing micro erosion meter (TMEM) on vertical rock surfaces, temporarily removing the slab from the operating position, so that measurements can be collected horizontally. Sources of errors and preliminary results, besides the limits and applicability of the method, are discussed.
We have tested the RRS method in the Gulf of Trieste, on a micro-tidal rock coast, collecting data from 7 stations between -0.75 m and +0.75 m m.s.l. The rock surface of the slab was surveyed between November 2007 and November 2008. During this period, the surface varied between -0.127 mm/yr (rising) and 0.034 mm/yr (lowering), according to the elevation of the stations. In the same period, standard deviation increased downward and varied between 0.003 and 0.045.
Beside the TMEM surveying, we have acquired near-monthly photographic images, in order to observe the biological colonisation of the slab. Monthly photographic comparison of the vertical slab indicates that biological colonisation affected mainly the mid-lower portion of the slab, sometimes preventing the collection of measurements.
Preliminary data suggests that the limestone surface lowered mostly in the upper part, while the lower part is strongly affected by algal growth. Consequently, data indicating surface rising is statistically less significant than data indicating surface lowering. Even the RRS used in the intertidal zone provides new interesting data to study weathering and erosion processes on limestone coasts, the first year of surveying suggests that this technique requires longer periods to address the TMEM data to explain geomorphological questions
Registrazione della temperatura del mare in tre stazioni del Golfo di Trieste (1997-1998)
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Approccio sistemico allo studio di comunità vegetali marine: herbaria e collezioni vive
No full textProtection effects on fish, and comparison of two visual-census techniques in shallow artificial rocky habitats in the northern Adriatic Sea
No full textFish assemblages associated with shallow (4-7 in deep) artificial rocky habitats (i.e. breakwaters) have been assessed between July 2002 and September 2003, at the marine protected a rea of Miramare and adjacent areas outside the reserve (northern Adriatic sea). Our purpose was to: (1) detect possible differences between 'protected vs fished' breakwaters; and (2) compare two visual-census techniques for fish assessment (i.e. strip transects vs stationary points). The fish assemblages observed between protected and fished breakwaters during all four sampling periods were statistically different. More fish taxa were found at the protected than fished breakwaters, while there was no difference in total fish density. Most fish species targeted by fisheries had a greater density (e.g. Sciaena umbra, Dicentrarchus labrax, Sparus aurata, Diplodus vulgaris, Diplodus sargus and Diplodus puntazzo) and/or size (e.g. S. aurata and D. aunularis) at the protected than fished breakwaters. There was a significant difference in fish assemblages due to assessment method. In general, the number of taxa was greater when assessed by strip transects than stationary points. fish density was almost unaffected by the method used, while total density of demersal fish (i.e. excluding schooling species) tended to be greater when evaluated by strip transects, although the difference was statistically significant only in one sampling period out of four. These results indicate that protection from fishing may have the potential to influence fish assemblages associated with breakwaters. Additionally, caution should be used when comparing fish assemblage data collected by different visual assessment techniques
The non-tropical coral Cladocora caespitosa as the new climate archive for the Mediterranean: high-resolution (~weekly) trace element systematics
No full textHigh-resolution (similar to weekly) laser ablation ICP-MS trace element analyses (B, Sr, U, Mg, Ba) are reported for the scleractinian coral Cladocora caespitosa, collected from the Northern Adriatic Sea. Geochemical ratios (Sr/Ca, B/Ca, Mg/Ca, U/Ca, Ba/Ca) were measured in a 38-mm long (similar to 10 years' growth) external coralline portion (wall region) and generally exhibit a close relationship with the in situ measured (weekly-fortnightly) data on sea surface temperature (SST), available for the last 6 years. In particular, B/Ca ratios tuned to fine-scale variations in SST show a high degree of correlation (r = -0.856, n = 136) with SST, and indicate that coral calcification only occurs above a minimum temperature threshold of 14-16 degrees C. In addition, the ranges of trace element variability are larger than those typically recorded in tropical corals, consistent with the large seasonal variations in SST of the Adriatic. This study thus demonstrates the feasibility of extracting and exploiting high-resolution geochemical records from non-tropical corals such as C. caespitosa as a proxy for SST
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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