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INTEGRATED ASSESSMENT OF GEOMORPHOLOGICAL AND VEGETATION DYNAMICS IN A COMPLEX DUNEFIELD. CAPO COMINO CASE STUDY (NE SARDINIA, ITALY).
Full text linkThe coastal environment is increasingly subject to utilization and anthropogenic disturbance. Currently a large proportion of the worldwide human population lives close to the coastline and this has led to the modification – and often the deterioration – of many previously intact coasts and ecosystems. In particular, the marketing of coastal recreation has increased drastically during the last century obliterating many natural systems. As a result, many coastal systems of the world are in advanced stages of degradation (e.g. with the elimination of native and endemic species and the introduction of the exotics, or the erosive processes induced by human modification of the natural environment, in addition to the natural erosion to which coasts are exposed (Pranzini and Rossi, 2000). In the worst cases, coastal ecosystems have been completely removed in the process of providing living space for the encroaching human population.
Dunes, beaches, coastal wetlands and salt marshes are generally considered as ecosystems at risk of loss as they are of high potential economic value or sources of biodiversity for coastal management schemes (e.g. biodiversity protection, ICZM protocols following the Barcelona protocol, 1978). The scientific investigation and understanding of natural processes in coastal ecosystems forms the basis of appropriate conservation and protection activities.
The present study investigates the development of an integrated methodology for the characterization of costal dune systems. It aims to produce a general overview of the Capo Comino landscape and its evolution to aid strategic planning decisions for enhancing the environmental sustainability of this natural system.
Focus has been given to the most relevant elements of the dunefield, such as its morphological aspect, the influence of the climate on its evolution and the distribution of vegetation.
A preliminary study of the general setting of the dunefield area allowed the development of a novel procedure for monitoring the dunes, integrating remote sensing strategies, in-situ measurements and data organization using geographical information systems (GIS).
The phases of this project may be summarized thus:
- Review of the existing literature
Coastal dunes have a worldwide distribution and they are characterized by a variety of forms exhibiting successional changes in geomorphology and ecological associations. The central topic for this phase of the research was the analysis of the studies focused on spatial and temporal variation in morphology, the sequences of biological succession in dune types and their adaptation to environmental stresses.
From the morphological point of view, coastal dunes are highly variable in form and dimensions and their current aspect is the consequence of stabilization and destabilization processes (Nordstrom et al., 1991; Psuty, 1997, 1999; Hesp, 2004, 2006; Martinez and Psuty, 2004). The main morphological constraints for their development are related to sediment supply, wind conditions, stabilizing vegetation and human interaction. Furthermore, in coastal environments the dichotomy between the dunes and the beach is a very significant factor.
With regard to vegetation, succession on coastal dunes has been the focus of many researches starting around a century ago (initial studies were carried out by Steinheil in 1832 and Cowles in 1899). In the present study vegetation associations and their distribution form the main topic, using the phytosociological method.
- Identification of the available information for the study area
The state of knowledge for the local study area was determined from published sources. Further data such as aerial and satellite images were evaluated and the vegetation analysis was carried out based on the existing literature that describes the main associations of Mediterranean coastal dune environments (Géhu, 1986; Géhu et al., 1984; Géhu and Biondi, 1994a, 1994b, 1995; Biondi 1999, 2007) and, in particular, of Sardinian coasts (Arrigoni, 1996; Bartolo et al., 1992; Biondi et al., 2001; Biondi and Bagella 2005; Filigheddu and Valsecchi, 2001).
- General setting of the study area
Investigation of the geology and geomorphology of the area, the wind-wave climate and bioclimatic indices were undertaken. Remote sensing analyses provided an essential overview of the general evolution and morphological complexity of this sector. Morphological and vegetation analyses were carried out on the two principal physionomic units of the coast: the dunefield and the beach. Results of vegetation data allowed a more precise delimitation and spatial distribution of plant associations and the characterization of two new sub-associations.
A bathymetric survey including the collection of seafloor sediment samples were also carried out for the characterization of the nearshore system.
All collected data and spatial analyses were ultimately implemented into a GIS, thereby allowing cross analysis of the information stored in the geodatabase to obtain both a qualitative and quantitative description of the landscape and the main morphological and vegetation characteristics of the environment.
- Monitoring program
The procedure integrates morphological and vegetational data - with several sedimentological considerations – in order to test a novel and readily applicable procedure for coastal dune monitoring. Three field measurement campaigns were carried out during the PhD program. This included measurements of the main geomorphological features with the integration of vegetation distribution along specific transects. Samples of the sediments of the beach and dunefield were collected in order to give further information concerning the grain sizes and the aeolic transport of sand. This research demonstrates that the dynamic processes and disturbances are well recognizable along transects. Therefore it is possible to monitor the general status of a study area using a small number of geomorphological and vegetation profiles. This integrated methodology promises a precise, effective and rapid procedure for the monitoring of coastal dunefields
An integrated monitoring procedure of coastal dune fields : The example of Capo-Comino area (NE-Sardinia, Italy)
No full textMonitoring plans are very important in order to improve ICZM protocols because of their contribution to the analysis, the conservation and the preservation of coastal sandy ecosystems.
Multidisciplinary studies are required for a well understanding of natural systems’evolution in consideration of their delicate equilibrium and dynamics. In fact, as an example, coastal dune fields fell the effects of natural and anthropic constrains and they react relatively fast to these stress.
We present the results of the experimentation of a new procedure of monitoring, that relates the morphological and sedimentological characteristics of the dune system and those of the vegetal associations that identify it. We suggest obtaining the best possible description of the landscape in quali-quantitative values by different disciplines.
This method plans a first essential analysis by remote sensing and a following field work collecting sedimentological, morphological and vegetational data (by phytosociological method) along several transects, systematically repeated in the years in order to highlight the medium-long term changes.
The use of survey systems, based on vegetal associations’ distribution, allows planning a strategy for the geomorphological and topographical survey that is/were simpler and faster if you have to work on huge study areas. In fact, as an example, considering the distribution and the ecological valence of the associations, it’s possible to give indications about dune field sides, using some enough reliable interpolations.
After a first application in an anthropic study area, Platamona (North Sardinia) (1, 2), we improved our studies in Capo Comino area. This area, characterized by natural and very complex conditions and only partially included in SIC-ITB020012, has been monitoring from 2003 (3) until now. In order to better understand the actual dynamics in the dune field, it has also been very important to study the submarine beach in a morpho-sedimentological point of view – by bathymetric lines and sample’s collection – and by the observation and the mapping of Posidonia oceanica meadows because their considerable importance on the sediment dynamics.
In general results show a slow erosive trend, highlighted by morphological and vegetational changes. We found the degradation - and sometimes the disappearance - of few phytocenosis in the dune field.
1) Balduzzi I., Bozzano A., Corradi N., Mariotti L.M., Vagge I. (2004). The evolution of the dune fields of Platamona-Marritza (Northern Sardinia) using remote sensing and aerial imagery. Chemistry&Ecology, Vol. 22 N° 4 (1): 371-381.
2) Vagge I., Corradi N., Ferrari M., Balduzzi I., Mariotti L.M. (2007). Aspetti vegetazionali e morfo-sedimentologici dei campi dunari di Platamona-Marritiza con particolare riguardo all'area di Marina di Sorso (Sardegna settentrionale). Fitosociologia 44 (1): 33-48.
3) Balduzzi I., Corradi N., Ferrari M., Vagge I. (2009). First observations about morpho-sedimentological and vegetational aspects of the dune field of S.Ena’ – Sa Chitta and Iscra Ruja coast (NE- Sardinia). 45th International Conference SISV & FIP "Biodiversity Hotspots in the Mediterranean Area", Cagliari (IT), 22-24 and 25-29 June 2009, p. 185 (abs.)
Le contrôle de l’érosion dans les systèmes barrière-lagune: le champ dunaire de Capo Comino (Sardaigne nord-orientale, Italie) = The erosion of the barrier system of Capo Comino (North-East Sardinia, Italy)
Full text linkThe study of the delicate balances of the coasts has a crescent interest in the scientific and administrative communities because of the role of the coastal systems in the economic development. Indeed, during the 70s the littoral zone underwent to the strong urban development and tourist industry. Now the main need is to find an equilibrium between the necessities of the protection of the coastal environment and the human needs (ICZM Protocols), following the target of the preservation of the beaches and the coastal systems.
The coast of Capo Comino, located in the north-eastern coast of Sardinia and partially included into a Zone of Community Interest ( SIC-ITB020012), is not influenced by human impact.
The analysis of aerial photos allowed the study of the evolution of the coastline, the dune field and its vegetation between 1954 and the 2006. The field monitoring of the dunes (2003-2011) was also made by transects, in order to evaluate the morpho-sedimentological and vegetation dynamic of this sector.
The data presented in this paper allow to understand that the erosion of the area is not strong and the regradation of the coastline is about 10-15 meters in the northern sector and 40 meters in the central one.
The migration of the dunes, instead, is very important, with the mouvement of huge volumes of sand. The number and areas of the blowouts has increased too.L’étude des équilibres délicats des systèmes littoraux connait un intérêt croissant dans les communautés sciéntifiques et administratives pour l’importance que les systèmes côtiers ont dans le développement économique des régions littorales. En effet, la bande côtière a été très intéressée par le développement urbanistique et l'industrie touristique qui doivent maintenant trouver un point d'équilibre (ICZM Protocols) avec les nécessités de protection de ce milieu fragile, tant pour le patrimoine naturel que pour la conservation des plages face à l’érosion.
Le littoral de Capo Comino, situé sur la côte nord-orientale de la Sardaigne et partiellement inséré dans une Zone d'Intérêt Communautaire (SIC-ITB020012), est encore peu soumis aux pressions anthropiques.
L’analyse des photos aériennes a permis l'étude de l'évolution de la ligne de rivage, des champs dunaires et de la végétation entre 1954 et 2006. Le suivi du champ dunaire (2003-2011) a été effectué par des transects, de façon à pouvoir analyser l'évolution morpho-sédimentaire et végétale du secteur.
Les données présentées dans ce travail ont permis de relever que l’érosion du littoral est très réduite : le recul de la ligne de rivage a atteint 10-15 mètres dans le secteur septentrional et environ 40 mètres dans une petite portion du secteur central. On a surtout relevé une augmentation des zones de déflation et des blowouts, avec une migration importante des volumes de sable le long de la direction principale de transport et la formation de nombreuses zones d’érosion éolienne
Monitoring and Management of coastal Habitats : Capo Comino Case Study (NE Sardinia, Italy)
No full textIt’s well-known that coastal systems are characterized by a delicate equilibrium and strong dynamics. After the census
of the priority habitats and the institution of SICs (Site of Community Importance), the monitoring and management are
a necessary step in order to protect their biodiversity.
From this point of view we present the results of the test of a new monitoring procedure on coastal dune fields, that
integrates few different sciences (geomorphology, sedimentology and botany). This method plans a first essential analysis
by remote sensing and a following field work in order to collect sedimentological, morphological and vegetational data
(by phytosociological method) along several transects, systematically repeated.
Sardinia (Italy) was chosen like our experimental laboratory. After a first application in an anthropic study area, Platamona
(N Sardinia) (Balduzzi et al., 2004, Vagge et al., 2007), we directed our studies to Capo Comino area, characterized by
natural and very complex conditions.
Capo Comino area, only partially included in SIC-ITB020012, has been monitoring from 2003 until now. Results show a
slow erosive trend, highlighted by morphological and vegetational changes. We found the degradation - and sometimes
the disappearance - of few priority habitats, in particular 1120 (Posidonia beds - Posidonion oceanicae), 2120 (shifting
dunes along the shoreline with Ammophila arenaria – white dunes), 2210 (Crucianellion maritimae fixed beach dunes)
and 2250 (coastal dunes with Juniperus spp.).
Balduzzi I., Bozzano A., Corradi N., Mariotti L.M., Vagge I. (2004). The evolution of the dune fields of Platamona-Marritza
(Northern Sardinia) using remote sensing and aerial imagery. Chemistry&Ecology, Vol. 22 N° 4 (1): 371-381.
Vagge I., Corradi N., Ferrari M., Balduzzi I., Mariotti L.M. (2007). Aspetti vegetazionali e morfo-sedimentologici dei
campi dunari di Platamona-Marritiza con particolare riguardo all’area di Marina di Sorso (Sardegna settentrionale).
Fitosociologia 44 (1): 33-48
Applicazioni GIS per lo studio degli aspetti morfologico-vegetazionali del campo dunare di Capo Comino (Sardegna NE)
No full textHay meadows and grasslands of Valcuvia Valley (Varese, Italy) : First observations
No full textChanging dynamics in land use are one of the most interesting processes in environmental monitoring referring to urbanisation processes and intensive agriculture diffusion. These factors usually cause alterations, environmental degradation and neglect. In order to fight these dynamics, it is necessary to devise environmental and agriculture politics based on an up-to-date knowledge of environmental sectors. In hill, piedmont and mountain areas, these processes are generally due to neglect phenomena, an uncalibrated management, some belated and uneffective interventions and the agriculture land attrition. In agriculture sector, the most suffering sectors seem to be the hay meadows and the grasslands. They are always been representing the cornerstone of the mountain agriculture economy but today it seems they are addressed to a strong quali-quantitative contraction.
In this work, we aim at dealing this problem and, in particular, to analyse by different methods the hay meadows and the grasslands of Valcuvia valley. We deepened the general characteristics of the study area, recovering the historical and actual cartography and organising it in a GIS system in order to integrate the territorial, the geomorphological, the lithological, the pedological and bioclimatic themes.
We analysed the flora and the vegetation (by phytosociological method) of the area and in particular the Festuco-Brometea and the Molinio-Arrhenatheretea meadows.
We studied the ecology and the productivity of these phytocenosis by Ellenberg's (1) and Landolt's (2) ecological indicators and by the pastoral value (3). These data are very interesting in order to have a better environmental overview.
The results highlight a higher nutrient content and a better ecological condition in hay meadows than in grasslands, with a pastoral value indicating a good quality of the present species.
Referring to the pastures, we highlight the critical aspects of the management typology itself. In fact, we observed a less nutrient content and a less quality of the pastoral species.
We also used few cartographic techniques (diachronic analysis of land use) in order to understand the dynamics referred to land use coverage classes. In general, results show a gradual increase of woods to the detriment of arable lands and permanent fodder meadows.
In the past centuries, urban areas quickly grew. This evolution, in general very common in Alpine and Apennine regions, highlights a worrying situation with a general regression of traditional agricultural systems. Pastures and grasslands halfway up the slope decreased, as the cultivated fields at the valley bottom.
If on the one hand woods’ areas are increasing with an extension of the natural lands, on the other hand the loss of meadows and cultivated fields inevitably leads to a decrease of floristic and phytocenotic biodiversity.
The study will continue with further analysis concerning the grassland associations and all vegetation of the valley. The aim is to draw up a map of the vegetation series in order to better understand the evolutive dynamics and to give good indications for a correct land management.
1) Pignatti S., Ellenberg H., Pietrosanti S. (1996). Ecograms fro phytosociological tables based on Ellenberg's Zeigerwarte. Ann. Bot. 54: 5-14.
2) Landolt E. (1977). Okologische Zeigerwerte zur Schweizer Flora. Ber. Geobot. Inst. ETH. 64: 64- 207, Zurich.
3) Cavallero A., Aceto P., Gorlier A., Lombardi G., Lonati M., Martinasso B., Tagliatori C. (2007). I tipi pastorali delle Alpi piemontesi. Alberto Perdisa Editore, Divisione Università
First observations about morpho-sedimentological and vegetational aspects of the dune field of S.Ena – Sa Chitta and Iscra Ruja coast (NE- Sardinia)
No full textThe aim of this project is the study of the evolution of the dune field of Capo Comino, between S.Ena-Sa Chitta and Iscra Ruja, by the integration of sedimentological, morphological and vegetational data. This approach has been already used in northern Sardinia (Platamona –SS) where we obtained very good results to understanding the evolution of the dune field and also to establish also the quality and naturality of this area (Balduzzi et al., 2004; Vagge et al., 2007). The target is to fix the elements for a future monitoring.
Our idea is to test the model in a non-anthropized coastline, that presents different local conditions.
In the first phase of this work we will analyze the general characteristics of the area like the bioclimate, the wind-wave climate, the mapping of the dune field by aerial photography analysis and their final cartographic representation. The second phase will imply several field measurements to study vegetational aspects (by phytosociological methods) in order to establish the present phytocenosis, their ecology and dynamic. It will be also possible to obtain several morphological and sedimentological data in order to highlight the characteristics of the sedimentary environment and the aeolian transport.
The integration of vegetational, sedimentological and morphological data will be obtain by the analysis of several transects carried out along the lines of dominant winds, that will outline the dune field. Vegetational data and sedimentological samples will be collect along these transects to allow a correct interpretation about coastline evolution.
The previous vegetational and sedimentological data, the satellite and cartographic reliefs and field measurements have already allowed to establish that, even if the anthropic impact is not so considerable, the dune field had some modifications and a considerable erosive process due to several factors (not in the least the natural sea ingression due to storm events). Erosion processes seem to hit the beach, in particular in the central sector that is subjected to the storms coming from the Tyrrhenian Sea. The most wide and high dunes are located in the southern sector of the beach where the dune field have its maximum extension and the phytocenosis have good quality and naturality. The back dune is occupied by some agricultural land uses that sometimes were be taken from the levelling of the dune field and were cultivated in the last few years. Balduzzi I., Bozzano A., Corradi N., Mariotti L.M., Vagge I., 2004 - The evolution of the dune fields of Platamona-Marritza (Northern Sardinia) using remote sensing and aerial imagery. Chemistry&Ecology Vol. 22 N° 4 (1): 371-381. Vagge I., Corradi N., Ferrari M., Balduzzi I. & Mariotti L.M., 2007 - Aspetti vegetazionali e morfo-sedimentologici dei campi dunari di Platamona-Marritiza con particolare riguardo all'area di Marina di Sorso (Sardegna settentrionale). Fitosociologia 44 (1): 33-48
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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