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The mediterranean coast of Andalusia (sw spain): the impacts of human coastal structures
No full textSpanish coasts, especially the Andalusia Mediterranean one, were affected over time by progressive urbanization
and associated construction of defense structures. Such structures protected small coastal sectors but at places
triggered processes of coastal erosion and associated degradation of habitats and ecosystems. A correct management
of coastal areas must be based on the monitoring of coastal evolution and human pressure. A useful tool to
evaluate the level of human anthropization is the estimation of the "Coastal Armouring", e.g. the quantification of
coastal defense structures, infrastructures, ports, etc.
In this study, available aerial photographs and satellite images from 1956 to 2011 were scanned and geo-referenced
and used for the quantitative assessment of coastal human constructions impact on the studied coastal area. The so
called coefficient of technogenous impact (K) was used. It results from the relationship between the total length
of all maritime structures (groins, moles, seawalls, dikes, channels, etc.) and the entire length of the study coastal
section. For this purpose, the Andalusia coast, about 500 km in length, was divided into sections of 1 km. For each
one of such sections the technogenous impact was calculated in the 1956 and 2011 documents.
The analysis showed that the degree of anthropization in some areas (for example the Port of Montril) has
increased considerably, triggering degradation processes in the nearby coastal areas. Results also evidenced as, in
many cases, greatest human impacts are linked to the progressive construction of coastal defense.
The lack of a general strategy to combat the erosion problem and the urgency in the short term to protect specific
parts of the coast led to a reactive approach based initially in the construction of hard structures. Such interventions
locally solved erosion problems but gave rise to drowndrift erosion according to the “domino” effect. A more
general management plan is needed, essentially based on the by-pass of ports and harbors and beach nourishment
works
Medium-term shoreline evolution of the mediterranean coast of Andalusia (SW Spain)
No full textCoastal environment is a dynamic system in which numerous natural processes are continuously actuating
and interacting among them. As a result, geomorphologic, physical and biological characteristics of coastal
environments are constantly changing. Such dynamic balance is nowadays seriously threatened by the strong and
increasing anthropic pressure that favors erosion processes, and the associated loss of environmental, ecologic and
economic aspects. Sandy beaches are the most vulnerable environments in coastal areas.
The aim of this work was to reconstruct the historical evolution of the Mediterranean coastline of Andalusia,
Spain. The investigated area is about 500 km in length and includes the provinces of Cadiz, Malaga, Granada
and Almeria. It is essentially composed by cliffed sectors with sand and gravel pocket beaches constituting
independent morphological cells of different dimensions.
This study was based on the analysis of aerial photos and satellite images covering a period of 55 years, between
1956 and 2011. Aerial photos were scanned and geo-referenced in order to solve scale and distortion problems.
The shoreline was considered and mapped through the identification of the wet / dry sand limit which coincides
with the line of maximum run-up; this indicator - representing the shoreline at the moment of the photo - is
the most easily identifiable and representative one in microtidal coastal environments. Since shoreline position
is linked to beach profile characteristics and to waves, tide and wind conditions at the moment of the photo,
such parameters were taken into account in the calculation of shoreline position and changes. Specifically,
retreat/accretion changes were reconstructed applying the DSAS method (Digital Shoreline Analysis System)
proposed by the US Geological Survey.
Significant beach accretion was observed at Playa La Mamola (Granada), with +1 m/y, because the construction
of five breakwaters, and at Playa El Cantal (Almeria) and close to Garrucha harbor, with values of +2 m/y.
Erosion rates ranged from -0.4 m/y (at Playa Casarones, Rubite) and -0.7 m/y (at Playa Castillos de Baños,
Granada) to c. -2 m/y (at Punta de los Hornicos, Almeria).
The analysis of coastline evolution revealed as the distribution of erosion areas is strictly related to the incorrect
design of coastal structures and their negative effects on downdrift areas. Obtained results clearly evidenced as, in
order to evaluate the efficiency of emplaced coastal defense structures, a continuous coastal evolution monitoring
plan should be implemented
Decadal evolution of coastline armouring along the Mediterranean Andalusia littoral (South of Spain)
No full textEmplacement of hard coastal defence structures, such as seawalls, revetments, groins and breakwaters,
or even ports, harbours and marinas, is commonly known as coastline armouring. This paper deals with
coastal armouring evolution along the 546 km Mediterranean coast of Andalusia (Spain). It is based on
photo interpretation and GIS tools, which have been employed to map coastal structure emplacement
and evolution by analysis of 1956, 1977, 2001 and 2010 aerial photos. Additionally the coefficient of
infrastructural impact K, which represented the relation between the total length of maritime structures
and the length of the study coastal section, was obtained - i.e. minimal at 0.001 K < 0.1; average when
0.1 K < 0.5; maximal at 0.5 K < 1.0 and extreme, when K 1.0.
In the mid 50s, coastal zones presented a very low level of armouring and the most important settlements
were coastal towns and associated fishing communities. The total length of anthropogenic
structures, 11 ports and a few protection structures, gave rise to K values ranging from “minimum” (with
average K 1⁄4 0.07) to K “extreme” (K 1⁄4 2.5 in 8 sectors).
During the 60s and 70s, the armoured coastline length increased from 42.1 (1956) to 98.2 km (in 1977).
The “minimum” K value maintained the same average value (0.07) but affected 10 sectors. The “extreme”
K value increased the average value to 3.6 and affected 25 sectors. The above was essentially linked to
coastal tourism development under an extreme laissez-faire politico-economic regime: several ports
were enlarged and new marinas constructed specially along the Costa del Sol. Induced coastal retreat
processes were counteracted by progressive groin emplacement to enlarge tourist beaches and/or halt
coastal erosion: 42 groins and 1 breakwater in 1977, some 8 fold increase with respect to 1956. Revetments
and seawalls occupied a total amount of 7.6 km.
Coastal occupation modalities from the mid 70s to 2001 were similar to the previous period. The
armoured coastline length increased from 98.2 to 182.3 km, with “minimum” K values (average: 0.09)
recorded in 15 sectors and “extreme” values (average K 1⁄4 4.7) recorded in 33 sectors. Coastal occupation
and tourism development did not record significant improvements during 2001e2010 and K values
recorded a small increase.
Approaches used to halt beach erosion were coastal structures as coastal tourism was the main beach
management target, carried out essentially by increasing beach carrying capacity without consideration
of ecological and environmental aspects. In the last few decades, coastal defence policies experienced
important changes based on reshaping/removal of hard structures and the realization of nourishment
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
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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