Beach zone evolution

Coastal lagoons and dunes are of great ecological importance, not only for providing habitats for rare flora and fauna, but also for protecting coastal areas from rising sea levels and storms, etc. Even though these features are unique for sustainable development and are extremely important to the natural environment and economy, they are one of the most vulnerable and threatened ecosystems due to their small size. The western coasts of Naxos (central Aegean Sea) represent an example of such phenomena, with various wetlands bordered by low-lying sand dunes. The aim of our study is to assess the vulnerability and pressures of the western coasts of Naxos Isl. by taking into consideration both natural and anthropogenic factors. We used a variety of approaches for the environmental and geomorphological study of the coastal zone to achieve this goal, including: (a) study of aerial photography from 1960 until today, (b) systematic seasonal aerial monitoring by drone, since 2015, (c) use of DGPS for the mapping of the coastal zone and for obtaining detailed topographic sections, and (d) dune mapping. Our findings reveal the vulnerability of the western coasts of Naxos due to sea level rise, tectonic subsidence, and a variety of anthropogenic pressures, such as uncontrolled parking, vegetation uprooting, sand extractions, and heavy touristic traffic. Therefore, the protection of the sand dunes, their restoration where they have been eroded, the definition of a zone of control, and restriction of human activities must be a key priority.

This contribution presents the results of a study on the shoreline variability of a natural perched urban beach (Ammoudara, N. Crete, Greece). Shoreline variability was monitored in high spatio-temporal resolution using time series of coastal video images and a novel, fully automated 2-D shoreline detection algorithm. Ten-month video monitoring showed that cross-shore shoreline change was, in some areas, up to 8 m with adjacent sections of the shoreline showing contrasting patterns of beach loss or gain. Variability increased in spring/early summer and stabilized until the end of the summer when partial beach recovery commenced. Correlation of the patterns of beach change with wave forcing (as recorded at an offshore wave buoy) is not straightforward; the only discernible association was that particularly energetic waves from the northern sector can trigger changes in the patterns of shoreline variability and that increased variability might be sustained by increases in offshore wave steepness. It was also found that the fronting beachrock reef exerts significant geological control on beach hydrodynamics. Hydrodynamic modelling and observations during an energetic event showed that the reef can filter wave energy in a highly differential manner, depending on its local architecture. In some areas, the reef allows only low-energy waves to impinge on the shoreline, whereas elsewhere penetration of higher waves is facilitated by the low elevation and limited width of the reef or by the presence of an inlet. Wave/reef interaction can also generate complex circulation patterns, including rip currents that appeared to be also constrained by the reef architecture.

The aim of the present study is to investigate the morphodynamic regime of the coastal area of Xylokastro (north coast of Peloponnese), in order to identify and evaluate the processes controlling its formation and evolution. Within this concept, a number of factors have been considered and evaluated; near-shore morphometry and granulometry along shore-normal profiles, the direction and potential volumes of long-and cross-shore sediment transport the decadal and future trends of coastline displacement, the available information for terrestrial sediment influx and the geological processes operating in the broader coastal region of Xylokastro (i.e. subaqueous slides) as well as human interference. On the basis of these results, the formation and evolution of this coastal stretch seems to be governed primarily by the neotectonic activity and relative change of sea level rise, and secondarily by the wave-induced near-shore sediment transport; the role of the latter could be enhanced substantially by human intervention (i.e. construction of marina, seafront walls). Moreover, the expected eustatic increase in sea level by the year 2100, could cause a coastline retreat up to 9 m (SLR=0.38 m) or >19 m (SLR≥1 m).

Coastal lagoons and dunes are of great ecological importance, not only for providing habitats for rare flora and fauna, but also for protecting coastal areas from rising sea levels and storms, etc. Even though these features are unique for sustainable development and are extremely important to the natural environment and economy, they are one of the most vulnerable and threatened ecosystems due to their small size. The western coasts of Naxos (central Aegean Sea) represent an example of such phenomena, with various wetlands bordered by low-lying sand dunes. The aim of our study is to assess the vulnerability and pressures of the western coasts of Naxos Isl. by taking into consideration both natural and anthropogenic factors. We used a variety of approaches for the environmental and geomorphological study of the coastal zone to achieve this goal, including: (a) study of aerial photography from 1960 until today, (b) systematic seasonal aerial monitoring by drone, since 2015, (c) use o...

Erosion is a major threat for coasts worldwide, beaches in particular, which constitute one of the most valuable coastal landforms. Vulnerability assessments related to beach erosion may contribute to planning measures to counteract erosion by identifying, quantifying and ranking vulnerability. Herein, we present a new index, the Beach Vulnerability Index (BVI), which combines simplicity in calculations, easily obtainable data and low processing capacity. This approach provides results not only for different beaches, but also for different sectors of the same beach and enables the identification of the relative significance of the processes involved. It functions through the numerical approximation of indicators that correspond to the mechanisms related to the processes that control beach evolution, such as sediment availability, wave climate, beach morhodynamics and sea level change. The BVI is also intended to be used as a managerial tool for beach sustainability, including resilience to climate change impact on beach erosion.

The 7 kilometers long coastline of Marathon Gulf (East Attica, Greece), has been chosen for this study, in order to classify its coastal erosion, using the Coastal Vulnerability Index (CVI) through GIS technology, since several incidents of erosion have been identified during the past decades in the area. The CVI index is used for assessing the vulnerability of a coast to an anticipated future sea-level rise. It relates geological (coastal geomorphology, historical changes of coastline's position, coastal slopes) and oceanographic (wave height, run up and tidal range) variables in a semi-quantitative manner. We combined different kinds of datasets extracted from high resolution panchromatic aerial photographs of several time periods (1960-2010) and traced the contemporary shoreline by high accuracy surveying with Real Time Kinematic (RTK) GPS equipment. The interpretation of all shorelines required geo-statistical analysis in a Geographical Information System, in order to estimate the rate of shoreline change for a period of 53 years. Retreating rates were calculated for each section reaching the value of 0.6 m/yr. According to the produced CVI values (10.61-39.52), it is found that 46% of the coast has very high vulnerability, 20% high vulnerability, whilst 29% have low vulnerability. The area named "Plesti" at the southern part of the study area, a large segment at the coast of Nea Makri, the northern part of Agios Panteleimonas beach and the eastern estuary of the Inois river are those with the higher risk. These conclusions are in full agreement with the field observations.

The present study investigates recent and future evolution of the beach zone of Almiros Bay, one of the most touristic developed beaches of north Crete, in relation to its morphodynamic setting and the anticipated sea level rise. The beach zone is exposed to northerly winds, with maximum wave heights and periods of 4.3 m and 9 s, respectively. The comparison of the aerial photographs (1982)(1983)(1984)(1985)(1986)(1987)(1988)(1989)(1990)(1991)(1992)(1993)(1994)(1995)(1996) and a satellite image of 2007 have revealed an extended retreat of the beach zone, with its highest retreating rates (i.e. 0.6-0.8 m y -1 for the last 25 years) found at its central part. Moreover, an estimation of the future shoreline retreat, due to the anticipated sea level rise (i.e. 0.38 or 1 m for the year 2100), has shown that there is a potential coastal zone loss from 48% up to 100%, respectively. A gross evaluation of the economical impact due to the aforementioned beach loss accounts to approximately from $ 270,000 up to $ 720.000, annually.

The 7 kilometers long coastline of Marathon Gulf (East Attica, Greece), has been chosen for this study, in order to classify its coastal erosion, using the Coastal Vulnerability Index (CVI) through GIS technology, since several incidents of erosion have been identified during the past decades in the area. The CVI index is used for assessing the vulnerability of a coast to an anticipated future sea-level rise. It relates geological (coastal geomorphology, historical changes of coastline's position, coastal slopes) and oceanographic (wave height, run up and tidal range) variables in a semi-quantitative manner. We combined different kinds of datasets extracted from high resolution panchromatic aerial photographs of several time periods and traced the contemporary shoreline by high accuracy surveying with Real Time Kinematic (RTK) GPS equipment. The interpretation of all shorelines required geo-statistical analysis in a Geographical Information System, in order to estimate the rate of shoreline change for a period of 53 years. Retreating rates were calculated for each section reaching the value of 0.6 m/yr. According to the produced CVI values (10.61-39.52), it is found that 46% of the coast has very high vulnerability, 20% high vulnerability, whilst 29% have low vulnerability. The area named "Plesti" at the southern part of the study area, a large segment at the coast of Nea Makri, the northern part of Agios Panteleimonas beach and the eastern estuary of the Inois river are those with the higher risk. These conclusions are in full agreement with the field observations.

The coastal zone is a transitory zone between land and sea. Due to its importance to man, not only for its high food production but also for recreation, sea transportation and industrial activities, coastal zone receives high environmental pressure from him. This paper deals with degradation phenomena of the coastal zone in the west section of the River Nestos Delta, North Aegean Sea, with special stress on the geomorphological changes in the coastline. The length of the coastline in this part of river Nestos Delta (the Kavala-Chrisoupoli part), from Nea Karvali village to the west, up to the river mouth to the east, is around 35 km long. This section constitutes the biggest and more extended sector of the Nestos Delta; it is the section where the main course and the various branches of the river were located, in the past. Along the coastal zone of this section of the delta many lagoons, sand bars, spits, barrier islands, washover fans, etc. were developed in its geologic past. Some of these geoforms still exist, but the majority of them have been destroyed by physical and/or anthropogenic interventions. Two of the last interventions are the diversion and entrenchment of the river to the east, in early 50's and the construction of two high dams in the river course inland, in 2000. These human interventions deprived this land of flooding waters and sediments resulting in: (a) drying of most of the river channels and courses crossing this area of the river's delta, (b) erosion of the coastal landforms and retreat of the shoreline in the majority of the delta coasts. There are, of course, a few places along the coastline where deposition and accretion are still taking place. In more detail, along the coastline taken into consideration in the present paper, one can meet: • stretches with high erosion rates, like the Akroneri Cape (spit), the inner coastline of Keramoti bay (Kokala-Piges coast), the Monastiraki coastline, etc, • stretches with high accretion rates like the Keramoti peninsula/spit, and • stretches at equilibrium or low rate of change like the barrier (spit) west of Akroneri Cape up to Nea Karvali coast and a short stretch of the coastline southeast of Keramoti peninsula. Comparing the Delta coastline of 1945 (from available aerial photographs) and the coastline of 2002 (from high resolution satellite images), before the construction of the Thisavros and Platanovrisi high dams (period 1945-2002), it has been estimated that: 88% of the delta and the adjacent coastlines has been accreted while only 12% has been eroded. In other words, there was a surplus of accretion by 76% and the delta was procreated. Comparing the Delta coastline of 2002 (from high resolution satellite images) and the coastline of 2007 (from high resolution D-GPS field measurements), after the construction of the dams (period 2002-2007), it has been estimated that: only 39% of the delta and the adjacent coastlines has been accreted while 61% has been eroded. In other words, there was a surplus of erosion by 22% and the delta began to retreat.

In the current paper are presented the results of a multidisciplinary study (stratigraphical, sedimentological, geophysical and geochemical) combined with modern techniques (G.I.S. and remote seming). This study aims at integrating the natural and anthropogenic factors a/fecling the Korissia lagoon. It is a shallow coastal lagoon, communicating with the sea via an artificial channel. The area around the lagoon consists o.j' alluvial sediments hosting, in places, newly formed and/or "old" (pre-Holocene) sand-dunes, The broader area constitutes a post alpine sedimentOl)' hasin characterised by smooth morphological reliet' The lower stratigraphic unit of the post-alpine sequence L\ a Pleistocene marly formation, which was detected as the hasement (5-15 Ohm,m) by the geophysical survey. The resistivity-based basement rnap implies the existence ofa ''palaeo-gulf'' trending E W. These marls constitute the impermeable basemenr of a shallow aquifer hosted in the area. The sa/inily of the lagoon is very high during summer (>40psuj but it does not affect significanrly the wel!s around it. The lagoon is well oxygenated, while the wells have lower D. 0. values. Ammonia and nitroles arr? the mam inorganic Nitrogen forms, in the lagoon and the wells, respectively. Phosphorus is the limiting .factor for phytoplankton growth. Human activities affect the area that is in need oj' an environmental management plan in order to prevent ecofogical degradation.

The aim of the present study is to investigate the morphodynamic regime of the coastal area of Xylokastro (north coast of Peloponnese), in order to identify and evaluate the processes controlling its formation and evolution. Within this concept, a number of factors have been considered and evaluated; near-shore morphometry and granulometry along shore-normal profiles, the direction and potential volumes of long- and cross-shore sediment transport the decadal and future trends of coastline displacement, the available information for terrestrial sediment influx and the geological processes operating in the broader coastal region of Xylokastro (i.e. subaqueous slides) as well as human interference. On the basis of these results, the formation and evolution of this coastal stretch seems to be governed primarily by the neotectonic activity and relative change of sea level rise, and secondarily by the wave-induced near-shore sediment transport; the role of the latter could be enhanced sub...

In the current paper are presented the results of a multidisciplinary study (stratigraphical, sedimentological, geophysical and geochemical) combined with modern techniques (G.I.S. and remote seming). This study aims at integrating the natural and anthropogenic factors a/fecling the Korissia lagoon. It is a shallow coastal lagoon, communicating with the sea via an artificial channel. The area around the lagoon consists o.j' alluvial sediments hosting, in places, newly formed and/or "old" (pre-Holocene) sand-dunes, The broader area constitutes a post alpine sedimentOl)' hasin characterised by smooth morphological reliet' The lower stratigraphic unit of the post-alpine sequence L\ a Pleistocene marly formation, which was detected as the hasement (5-15 Ohm,m) by the geophysical survey. The resistivity-based basement rnap implies the existence ofa ''palaeo-gulf'' trending E W. These marls constitute the impermeable basemenr of a shallow aquifer hosted in the area. The sa/inily of the lagoon is very high during summer (>40psuj but it does not affect significanrly the wel!s around it. The lagoon is well oxygenated, while the wells have lower D. 0. values. Ammonia and nitroles arr? the mam inorganic Nitrogen forms, in the lagoon and the wells, respectively. Phosphorus is the limiting .factor for phytoplankton growth. Human activities affect the area that is in need oj' an environmental management plan in order to prevent ecofogical degradation.

The present study investigates recent and future evolution of the beach zone of Almiros Bay, one of the most touristic developed beaches of north Crete, in relation to its morphodynamic setting and the anticipated sea level rise. The beach zone is exposed to northerly winds, with maximum wave heights and periods of 4.3 m and 9 s, respectively. The comparison of the aerial photographs (1982-1996) and a satellite image of 2007 have revealed an extended retreat of the beach zone, with its highest retreating rates (i.e. 0.6-0.8 m y-1 for the last 25 years) found at its central part. Moreover, an estimation of the future shoreline retreat, due to the anticipated sea level rise (i.e. 0.38 or 1 m for the year 2100), has shown that there is a potential coastal zone loss from 48% up to 100%, respectively.

A hydrogeological study took place in the broader area of Mesologgi – Aitoliko lagoons (West Greece) aiming at the investigation of a) the hydrogeological conditions of the area as well as the surface and groundwater influences on the quality of the clay deposits found in the lagoons and b) the properties of the clay in order to be identified as "therapeutic peloids". Due to their location, the clay deposits could be influenced and possibly polluted from the surface waters. The aquifer of the unconsolidated formations presents low hydraulic conductivity, while the carbonate aquifer is bounded from the foregoing aquifer and therefore the possibility of clay pollution from the ground-water is very limited. pH of the sediments showing neutral and alkaline values, limits the mobility of some pollutants. Seawater affects some of the clay samples, which present high electrical con-ductivity. Iron and manganese show also high concentrations, while some of trace elements such as C...

This study focuses on the sedimentological and morphological features of Vravrona Beach, East Attica, in order to determine the seasonal changes in the textural group classification of the costal sediments, as well as, changes in coastline position . Additionally, Vravrona Beach has been chosen for the assessment of a potential coastal erosion, using the Coastal Vulnerability Index (CVI) through GIS technology, since several incidents of erosion have been identified during the past decades in the broader area of East Attica . For the composition of the beach profile in seasonal scale, cross sections were conducted along the beach from landward to seaward until approximately 10 m from the coastline. Beach width as well as the current coastline position for each season were measured with a differential GPS (DGPS). The land use at the landward upper limits of the study area were also measured. Along selected cross sections, sediment sampling was also conducted during January 2018 for the composition of the winter profile of the study area and during September 2018 for the composition of the summer profile of the study area. Sedimentological analyses were based on grain size distribution for the analysis of unconsolidated sediments by sieving and statistical parameters such as sorting, skewness, mean and kurtosis were calculating using GRADISTAT v. 0.4 software in order to determine the sedimentological features of the study area and the transport mechanism at the time of deposition. The textural group of the samples was also determined by classification. The grain size analysis of the samples, collected between the upper limit of the beach and the coastline during summer period, show that the majority of grains is described as slightly gravelly sand and gravelly sand, but during the winter period the grains are between gravely sand and sand. The samples collected from the coastline until approximately 10 m seaward are mainly described as slightly gravelly sand and sandy gravel for both sampling seasons . DGPS measurements of coastline position indicate changes that varies between 4.38 m to 7.41 m with a maximum value at 8.27 m. In agreement to field observations, DGPS measurements indicate an accumulation of sediments at the northern part of the beach during the winter period, while during summer period there is an accumulation of sediments at the southern part of the beach. Figure 1. Vravrona Beach, East Attica.

The study area of Vigla coastal zone is located at the W coast of Naxos, the largest island of Cycladic plateau. The study of sea-land interactions during Holocene in relation to the eustatic sea level oscillations as well as the geomorphologic observations and analyses on deposited sediments, aims to reveal the paleogeographic evolution of the landscape and its impact to the overall cultural development of the area. A geomorphological mapping of the coastal area along with the drilling of three boreholes has been accomplished. Moreover, a micro faunal analysis has been performed. Five samples of plant material, chart coal and shells were dated using AMS and Conventional radiocarbon techniques providing temporal control of the sediments. Sea level rise along with sea-land interactions to the landscape evolution and the transgression of sea in 5000 BP have been verified.

This study focuses on the phenomenon of erosion regarding the coastal dune system in Naxos island (Cyclades), Greece. In the western coastal zone of Naxos, several dune fields are observed. Despite the fact that erosion on the inland has become more intense during the last years, providing thus sufficient material for the development of new dune fields, the current dunes are retreating.

The flat terrestrial part of the coastal zone of the Paros Island (slope <2,5% for elevations 0-50 m), represents only the 19% of the total area of the island (193 km 2 ). More than 75% of the coastal zone consists of high and lower cliffs, whilst relatively flat and sandy (and/or pebble) beaches do not exceed the 17% of the coastline. The island receives a considerable amount of wave energy; this has its highest values (>1500 W/m) at the NE part of the island and its lowest at the SE "protected" and shallower area. Touristic (sandy/pebble) beaches have been developed along those parts of the coastline that characterized by vulnerable lithology associated with moderate wave activity.

The relief of the island of Samos is characterized by the Kerketeas mountain in the western part and the Karvouni mountain in the central part. The Geology of Samos consists of a metamorphic substratum, a non metamorphic unit, neogene and quaternary sediments. This island has been affected many times by natural hazards, such as forest fires, soil erosion, flash floods and gravity movements. The aim of this paper is to create an erosion risk map of Samos Island. This has been achieved by a series of separate stages, such as the creation of a database of geological, geomorphological and topographic data, extensive field observations and analyses of aerial photos and satellite images, within a GIS based platform. The final step involves the application of a functional relationship based on a probability model to input data consisting of the lithology, slope, mean altitude, and the vegetation-land use for each drainage basin to produce the final erosion risk map

The 7 kilometers long coastline of Marathon Gulf (East Attica, Greece), has been chosen for this study, in order to classify its coastal erosion, using the Coastal Vulnerability Index (CVI) through GIS technology, since several incidents of erosion have been identified during the past decades in the area. The CVI index is used for assessing the vulnerability of a coast to an anticipated future sea-level rise. It relates geological (coastal geomorphology, historical changes of coastline's position, coastal slopes) and oceanographic (wave height, run up and tidal range) variables in a semi-quantitative manner. We combined different kinds of datasets extracted from high resolution panchromatic aerial photographs of several time periods (1960-2010) and traced the contemporary shoreline by high accuracy surveying with Real Time Kinematic (RTK) GPS equipment. The interpretation of all shorelines required geo-statistical analysis in a Geographical Information System, in order to estimate the rate of shoreline change for a period of 53 years. Retreating rates were calculated for each section reaching the value of 0.6 m/yr. According to the produced CVI values (10.61-39.52), it is found that 46% of the coast has very high vulnerability, 20% high vulnerability, whilst 29% have low vulnerability. The area named "Plesti" at the southern part of the study area, a large segment at the coast of Nea Makri, the northern part of Agios Panteleimonas beach and the eastern estuary of the Inois river are those with the higher risk. These conclusions are in full agreement with the field observations.

Greek coastline that accounts more than 16.000 km hosts hundreds of beaches, which constitute a great touristic destination. However, no gathered information exists relative to its qualitative and quantitative characteristics (e.g. physicogeographical characteristics, artificial structures, nearby land use). Therefore, the development of a coastal database that would successfully concentrate all relative data, in the form of a National Inventory, could be a valuable tool for the management and the sustainable use and exploitation of beaches and the coastal zone. This work presents an example of the development of a beach inventory in the case of the beach zones of Heraklion and Lassithi counties in the Island of Crete, which is one of the most touristic areas in Greece. Data were initially abstracted from satellite images and combined with in situ observations carried out along 98 beaches with shoreline length >100 m. The collected data included geomorphological, topographic and bathymetric mapping, sediment sampling from the subaerial and underwater part and recording of artificial structures. The initial mapping showed that beaches represent only the 18%, with 74% of the total coastline to be rocky while 8% of the coastline host some kind of artificial intervention. The combination of satellite and in situ mapping led to the development of a coastal geomorphological map. Beach widths were found to be limited with the majority of beaches (59%) to have maximum widths less than 25 m, 35% to range between 25 and 50m and about 6% with maximum widths >50m. Concerning beach length, the threshold of 1000 m is overcome only by the 46% of the beaches. Beaches with very smooth slopes (<2.5) are infrequent (∼6%), whilst beaches with low slopes (2.5-5%) are the majority (42%) along with beaches with moderate slopes (5-7.5%) that account approximately the 32%. Beaches with high slopes (7.5-10%) are about 11%, whereas very high slopes and extremely high slopes are much less being equally to 6% and 3%, respectively. With respect to beach position, the majority of the south beaches are characterized by slopes of 5-7.5% " whilst most of the north beaches present lower slopes in the order of 2.5-5%. In terms of sediment texture, 41% of the beaches were found to consist mostly of medium and coarse sands (gS and (g)S) and 31% of gravels with some sand presence ((s)G and sG). The exclusively sandy beaches correspond to the 11% when the exclusively gravelly beaches accounts for 16%. North sided beaches were found to be more fine grained compared to the south beaches; this most probably is due to the more persistent wave regime. The main human interventions along the coast of the study area are associated with four main ports (Heraklion, Ag. Nikolaos, Sitia and Ierapetra) and twelve small fishing ports (twelve in the north, one in the east and eight in the south), coastal residential and touristic development, coastal protection works and river management schemes.

The present investigation introduces the development of a beach inventory, which will record, gather and depict information for beaches in an accurate way. The information, coming up from satellite images and ground-truthing with on-site field work, involves data concerning morphological and sedimentological characteristics of the beaches and all kinds of human intervention and presence on them. Information is gathered in a GIS geodata base and is, in turn, statistically elaborated. The coastline of the Heraklion and Lassithi regions (Crete) have been selected as case studies, in which detailed coastal mapping was carried out in 98 beach zones (with shoreline length >100 m). The statistical analysis of its characteristics showed that the south facing beaches are more coarse-grained, steeper and less human intervened, in relation to the north facing.

The nearshore wave and current conditions and the resulting nearshore circulation were measured with five wave recorders, on electromagnetic current meter, two ADVs and one ADCP, during a 6-day field experiment at the reef-protected Ammoudara beach. Storm waves breaking on the reef resulted in a shoreward water flow of 0.28 m 3 /s per meter of reef length, which produced a longshore current with a speed of 2.0 m/s at the shoreline and a seaward return flow through an opening of the reef. Subharmonic and infragravity oscillations were excited in the nearshore zone, affecting sediment transport and beach face morphodynamics.

The study area of Vigla coastal zone is located at the W coast of Naxos, the largest island of Cycladic plateau. The study of sea-land interactions during Holocene in relation to the eustatic sea level oscillations as well as the geomorphologic observations and analyses on deposited sediments, aims to reveal the paleogeographic evolution of the landscape and its impact to the overall cultural development of the area. A geomorphological mapping of the coastal area along with the drilling of three boreholes has been accomplished. Moreover, a micro faunal analysis has been performed. Five samples of plant material, chart coal and shells were dated using AMS and Conventional radiocarbon techniques providing temporal control of the sediments. Sea level rise along with sea-land interactions to the landscape evolution and the transgression of sea in 5000 BP have been verified.

Beaches are both sensitive and critical components of the coastal systems, as they are particularly vulnerable to environmental change (e.g., the sea level rise) and form valuable coastal ecosystems and economic resources. The objective of the present study has been to record the spatial characteristics and other attributes (e.g., topography, sediments and accessibility) of the 71 beaches of the E. Crete (Eastern Mediterranean) that are either already developed or have a reasonable development potential and assess their erosion risk under sea level rise. Beach retreats are predicted by ensembles of six cross-shore (1D) analytical and numerical morphodynamic models, set up/forced on the basis of collected/collated information and three sea level rise scenarios (0.26, 0.82 and 1.86 m); these retreats are then compared with the recorded maximum (dry) beach widths. Projections by the unified ensemble suggest that, in the case of a 0.26 m rise, 80 % of the examined beaches are to retreat by more than 20 and 16 % by more than 50 % of their maximum dry width. In the case of a 0.82 m rise, 72 % of the tested beaches are predicted to retreat by more than 50 % of their dry width and 21 % by a distance at least equal to their observed maximum dry widths. A sea level rise of 1.86 m represents a 'doom' scenario, as 75 % of the beaches are predicted to retreat by more than their maximum width. These results may be conservative, as other significant beach erosion factors (e.g., decreasing beach sediment supply) have not been considered.

This research concerns the evaluation of the depositional environment in Kifissos river, in N. faliro area (Greece). In order to retrieve the depositional history ten sampling boreholes (P1-P10) are made in the area of Piraeus-N. Faliro in 2005 from the coordination of EFA (and the director of the ARTEMIS-SHS. Only two boreholes (P2-P4) were selected for further sedimentological analysis as the most representative. After the description of its stratigraphic units, sampling had been followed. Forty samples were collected and they were sedimentologically and granulometrically studied through the laser granulometer Mastersizser 2000 of the Malvern Company. The available obtained data were statistically analysed through the program "Gradistat" to collect the appropriate results for the Passega method and the sedimentological indicators method (Folk and Ward).

Electrical resistivity tomography (ERT) technique is widely used in mapping subsurface electrical properties. In this study, ERT was used to map a beachrock outcrop, extended both inland, under beach sediments, and seawards, on and under seafloor sediments. Mapping of beachrock is considered important because it can help evaluate the lateral and vertical extend of the formation. Fast and reliable mapping of beachrocks may contribute in several applications like engineering and construction, coastal management, recreational reformation as well as scientific approaches like coastal evolution research, and palaeo-environmental studies. The outcome of the survey was the mapping of the formation with centimeter precision, especially towards the sea. Special processing was applied to the data in order to constrain the inversion procedure to include the known sea water layer.

Erosion is a major threat for coasts worldwide, beaches in particular, which constitute one of the most valuable coastal landforms. Vulnerability assessments related to beach erosion may contribute to planning measures to counteract erosion by identifying, quantifying and ranking vulnerability. Herein, we present a new index, the Beach Vulnerability Index (BVI), which combines simplicity in calculations, easily obtainable data and low processing capacity. This approach provides results not only for different beaches, but also for different sectors of the same beach and enables the identification of the relative significance of the processes involved. It functions through the numerical approximation of indicators that correspond to the mechanisms related to the processes that control beach evolution, such as sediment availability, wave climate, beach morhodynamics and sea level change. The BVI is also intended to be used as a managerial tool for beach sustainability, including resilience to climate change impact on beach erosion.

The aim of this paper is to examine the spatio-temporal, qualitative and quantitative changes in the natural environment and morphology of the coastal area of Vari, a suburb of Athens, Greece. The changes were studied using maps, aerial photographs and GIS techniques. Qualitative changes including man-made alterations that took place in the area of Vari bay during the last hundred

Being highly dynamic by nature, due to their changing hydrological regime and to the encroachment of urbanization, industrialization and changing patterns in agriculture, reliable and timely information of coastal areas is a prerequisite for their effective management. The aim of this paper is to assess the use of ERS-2 SAR satellite data to detect short period changes in the case of the R. Sperchios coastal area that is located at the eastern part of the Maliakos Gulf (near the middle of the east coast of the Greek mainland). A Landsat 7 (ETM+) image served as a reference for the interpretation of the ERS images. In order to highlight and detect the changes occurred in the study area two methods were applied. The first method is based on the creation of a Temporal Differentiate Image, consisted of the three ERS-2 images (Figure 1). The second method concerns the implementation of Principal Component Transform (PCT) on the three multitemporal scenes. The final images derived from th...

Beaches are both sensitive and critical components of the coastal systems, as they are particularly vulnerable to environmental change (e.g., the sea level rise) and form valuable coastal ecosystems and economic resources. The objective of the present study has been to record the spatial characteristics and other attributes (e.g., topography, sediments and accessibility) of the 71 beaches of the E. Crete (Eastern Mediterranean) that are either already developed or have a reasonable development potential and assess their erosion risk under sea level rise. Beach retreats are predicted by ensembles of six crosshore (1D) analytical and numerical morphodynamic models, set up/forced on the basis of collected/collated information and three sea level rise scenarios (0.26, 0.82 and 1.86 m); these retreats are then compared with the recorded maximum (dry) beach widths. Projections by the
unified ensemble suggest that, in the case of a 0.26 m rise, 80 % of the examined beaches are to retreat by more than 20 and 16 % by more than 50 % of their maximum dry width. In the case of a 0.82 m rise, 72 % of the tested beaches are predicted to retreat by more than 50 % of their dry width and 21 % by a distance at least equal to their observed maximum dry widths. A sea level rise of 1.86 m represents a ‘doom’ scenario, as 75 % of the beaches are predicted to retreat by more than their maximum width. These results may be conservative, as other significant beach erosion factors (e.g., decreasing beach sediment supply) have not been considered.

The present study investigates recent and future evolution of the beach zone of Almiros Bay, one of the most touristic developed beaches of north Crete, in relation to its morphodynamic setting and the anticipated sea level rise. The beach zone is exposed to northerly winds, with maximum wave heights and periods of 4.3 m and 9 s, respectively.
The comparison of the aerial photographs (1982-1996) and a satellite image of 2007 have revealed an extended retreat of the beach zone, with its highest retreating rates (i.e. 0.6-0.8 m y-1 for the last 25 years) found at its central part. Moreover, an estimation of the future shoreline retreat, due to the anticipated sea level rise (i.e. 0.38 or 1 m for the year 2100), has shown that there is a potential coastal zone loss from 48% up to 100%, respectively. A gross evaluation of the economical impact due to the aforementioned beach loss accounts to approximately from $ 270,000 up to $ 720.000, annually.

The geomorphological processes, which take place on the coastal zone, are influenced by a number of environmental factors, such as lithology, climate, biota, and oceanography. The present study investigated the causes of erosion taking place on the beach zones and on the coastal cliffs along the Island of Samos (eastern Aegean Sea). On the northern part of the island the coastline is characterised mainly by rocky and craggy coasts with the beach zones to be limited and in the form of a 'pocket' type of beach, while on the southern part by wide and long beach zones constituted by cobbles and pebbles. Intense coastal erosion takes place mainly on the rocky coasts on the northern and especially on the northwestern part of the island. In some coastal places intense coastal erosion causes problems not only to the infrastructure (road network), but also to near-coast people's properties. Coastal erosion is more intense on the northern coasts, than on the southern coasts, due to the differenced in the incoming wave energy, which is dominated by the more intense and frequent blowing northerly winds. Furthermore, it seems that coastline retreat is more often along parts of the coast consisting of marles, malry limestones and limestones.

The shallow bay of St. Georgios is situated in the northwestern part of the Naxos Island and it is characterized by a 2.7 km long sandy coast consisting of fine-grained (sandy) material. Sand dunes are the landward limit of the beach zone, whilst at the southwestern part of the coast an extensive lagoon plain has been formed. A partially emerged reef and the morphologically associated Manto islet protect the middle and southwestern part of the beach zone from the most frequent (>40% annually) incoming N waves and the highest NW waves (>3 m).

KOUTSOMICHOU I., POULOS S., EVELPIDOU N., ANAGNOSTOU CH., GHIONIS G. & VASSILOPOULOS A., The role of beachrock formations in the evolution of embayed coastal zones of Attica (Greece) in relation to sea level rise. The case of Kalyvia beach zone. (IT ISSN 0391-9838, 2009).

Erosion is a major threat for coasts worldwide, beaches in particular, which constitute one of the most valuable coastal landforms. Vulnerability assessments related to beach erosion may contribute to planning measures to counteract erosion by identifying, quantifying and ranking vulnerability. Herein, we present a new index, the Beach Vulnerability Index (BVI), which combines simplicity in calculations, easily obtainable data and low processing capacity. This approach provides results not only for different beaches, but also for different sectors of the same beach and enables the identification of the relative significance of the processes involved. It functions through the numerical approximation of indicators that correspond to the mechanisms related to the processes that control beach evolution, such as sediment availability, wave climate, beach morhodynamics and sea level change. The BVI is also intended to be used as a managerial tool for beach sustainability, including resilience to climate change impact on beach erosion.

Electrical resistivity tomography (ERT) technique is widely used in mapping subsurface electrical properties. In this study, ERT was used to map a beachrock outcrop, extended both inland, under beach sediments, and seawards, on and under seafloor sediments. Mapping of beachrock is considered important because it can help evaluate the lateral and vertical extend of the formation. Fast and reliable mapping of beachrocks may contribute in several applications like engineering and construction, coastal management, recreational reformation as well as scientific approaches like coastal evolution research, and palaeo-environmental studies. The outcome of the survey was the mapping of the formation with centimeter precision, especially towards the sea. Special processing was applied to the data in order to constrain the inversion procedure to include the known sea water layer.

The study area of Vigla coastal zone is located at the W coast of Naxos, the largest island of Cycladic plateau. The study of sea-land interactions during Holocene in relation to the eustatic sea level oscillations as well as the geomorphologic observations and analyses on deposited sediments, aims to reveal the paleogeographic evolution of the landscape and its impact to the overall cultural development of the area. A geomorphological mapping of the coastal area along with the drilling of three boreholes has been accomplished. Moreover, a micro faunal analysis has been performed. Five samples of plant material, chart coal and shells were dated using AMS and Conventional radiocarbon techniques providing temporal control of the sediments. Sea level rise along with sea-land interactions to the landscape evolution and the transgression of sea in 5000 BP have been verified.

ABsrRAct: Koursor'ltcl-tou I., Pot;t.os S., Everprnou N., Arrrcxosrou Cn., Gruoxts G. & VASSII-oPout-os A., The rola of beochtock fonnotions in thc euoltrtion of embal,sd coastol zones of Attica (Grcecc) in relotion to sen lcucl ise. Tlte cose of Kalyuin beach zone. (IT ISSN U91-9$8,2009). I'he coastline of Atdca incorporates a great number of pocket beaches, s,hicl.r are characterised further by the presencc of cxtensive beachrock formrtions. 'l'l.re present study concerns the cvolution (past, prescnt and futurc) of the Kalyvia beach zone, located ar the l'esrern coast of Artica 4nd at a distancc of 42 kn from the city of Athens. The subaerial part of the bcacl.r zonc consists of mixed materials (mainly sand, granules and glavcl), rvhile extensive beachrock fbrmations exisr on its shoreface. The beach is exposed primarily to southcrn s'ind-induced s'aves, the largest oi:thich (offshole rvave height up to 6ln and period >llsec) begin to bretrk at about 8 m of s'arcr depth and have ar run up crrpability o[ approximatell, 1.5 m. Most of rhe subaqueous part of the Kalyvia beach zonc is lithified, as the beachrocks cxtend fron rhe shoreline dos,n to >8 n of s'ater depth. This part of the bcach zone may be subdivided turther into three units: the deeper one (t'ater depths >7m), thc middle (deptlrs 5'6.5 m) and the upper unit (fi'om 4 rn depth up to the shoreline). This alnost continuous presence is relared to the gladual sea level rise during rhe upper I-Iolocene (past 6.000 years), indicating also a relrrrive climaric stability and/or homogeneitl' iulir* rhis period, ahhough some rnorphological and structural differences in rhe beachrock indicate changes either in thc rare of sea level rise or in the prevailing climatic conditions. Over the last decades, human activities and constructions have deprived the beach of hinrerland sedimenr supply, changing, therelbre, its scdimentological character. f)uring this period, beachrocks have played a 'protcctive role' stabilizing and reducing substantially rhe retreat of the beach zone, l'hich on the basis of the landrvard boundary displace-(") Uniuarsitl' of Athcns, Faculry 6f Gs6l6g), & Geoenuironnet!. ("") I-Iellenic Ccntrc for Motitte Research, Institute of Oceanographl,. (':'t't') l2ttrBc/giuttt-Fnnce-Ita\,-RonaniaGcotnorphologicolMeeting-IAG "Climatic Change and Related Landscapcsr, Sauono 26-29 Septembu 2007. 'l-hc orrthors uould likc to thdnk Issoris 1., Salontidi M, Gerakaris V., Milouanouic M., Andris P., Papanikoloou G, Bouziotopoulou N., for their dssistdnce during ficldtuotk cantpoigns, I.-D. Manto and L Giotitsas for thei contributic.tn in prccessing thc oeriol and satellite inages.

The beach vulnerability Index (BVI) that is presented in this study is dedicated to the assessment of vulnerability to erosion in the case of beach zones developed in microtidal environment, experiencing significant nearshore hydrodynamics. This approach combines the coastal system's susceptibility to change, with its natural ability to adapt to changing environmental conditions, including relative sea level change. The index incorporates a quantitative, although relative, measure of the coast's natural vulnerability to the effects of erosion processes. Subsequently, the developed BVI has been applied to two beach zones (i.e. Ammoudara and Almiros) located on the northern coast of Crete. It is revealed that the most important variables that control the beach zone evolution; in general and in particular the areas under investigation are the grain size, beach morphology and incoming wave energy. In the case of the Ammoudara beach zone, the western part is the most vulnerable as it is unprotected by a submerged reef, whose presence reduces, drastically, the incoming wave energy over its central and eastern parts. Along the shore of the Almiros beach zone, it is the western part less vulnerable to erosion processes, as it is 'sheltered" to the dominant NW incoming waves. It has also to be mentioned that the index values could not be used for comparison between different beach zones, as the maximum possible variability (100%) for individual parameters was not common between them.

The morphological characteristics of a coastal reef that is observed along the Ammoudara beach (6 km to the west of the city of Heraklion, Crete) are investigated in relation to the sedimentology and modern evolution of the adjacent beach zone. The reef has a length close to 4 km, a mean width close to 35m and is located at a distance of 60 m from the shoreline at an average water depth of 2.6m, while the seaward water depth exceeds 3m. Its height above the seafloor, exceeds 80 cm, reaching in places less than 0.5 m from the sea surface. It has two layers; the lower one which consists of fine grained (sandy) material and is approximately 40 cm thick and the upper layer, around 30 cm thick, consisting of relatively coarse-grained material (gravel and sand). Moreover, on the surface of the upper layer, runnels are observed, whilst distinguished cross bedding, similar to that observed in aeolian deposits, exists within the bottom layer. The reef is not present in front of the active mouths of the rivers Gazanos and Xiropotamos which debouch in the coastal area of Ammoudara. The western end of this submerged reef is attached to the beach face, exhibiting the characteristics of a typical beach-rock formation. On the basis of the above, it is concluded that the reef under investigation it is a submerged beach rock which indicates the position of a former coastline that is now submerged due to a relative sea level rise of approximately 0,5m.

The beach vulnerability Index (BVI) that is presented in this study is dedicated to the assessment of vulnerability to erosion in the case of beach zones developed in microtidal environment, experiencing significant nearshore hydrodynamics. This approach combines the coastal system’s susceptibility to change, with its natural ability to adapt to changing environmental conditions, including relative sea level change. The index incorporates a quantitative, although relative, measure of the coast’s natural vulnerability to the effects of erosion processes. Subsequently, the developed BVI has been applied to two beach zones (i.e. Ammoudara and Almiros) located on the northern coast of Crete. It is revealed that the most important variables that control the beach zone evolution; in general and in particular the areas under investigation are the grain size, beach morphology and incoming wave energy. In the case of the Ammoudara beach zone, the western part is the most vulnerable as it is unprotected by a submerged reef, whose presence reduces, drastically, the incoming wave energy over its central and eastern parts. Along the shore of the Almiros beach zone, it is the western part less vulnerable to erosion processes, as it is ‘sheltered” to the dominant NW incoming waves. It has also to be mentioned that the index values could not be used for comparison between different beach zones, as the maximum possible variability (100%) for individual parameters was not common between them.