Houston, J.R. and Dean, R.G., 2014. Shoreline change on the east coast of Florida.

A shoreline change data base for Florida dating back to the mid-1800s is unique in the United States, and perhaps the world, with thousands of shoreline change measurements at a nominal spacing of 300 m. Moreover, data are available on factors contributing to shoreline change, including beach nourishment, disposal of dredged sand outside the littoral zone, cutting of new inlets and subsequent growth of ebb shoals, and longshore sediment transport into and along the east coast of Florida. Effects of relative sea level rise can be estimated using the Bruun Rule. These factors should have caused significant shoreline recession since the mid-1800s, but instead, the east coast of Florida has experienced significant average shoreline advance. The formation of carbonate sand is shown not to account for this difference. Onshore transport of sand from beyond closure depth, probably during episodic storm events, is the only possible source of the large quantity of sand that has advanced on average the shoreline of Florida's east coast. For shorelines with significant offshore deposits of sand, it is possible that sea level rise in conjunction with wave action contributes to onshore transport and shoreline accretion.

Wang, L.; Coles, N.; Wu, C., and Wu, J., 2014. Effect of long-term reclamation on soil properties on a coastal plain, southeast China.

The coastal plain of Cixi City, in southeast China, has experienced more than a thousand years of land reclamation history. Since 1047, 11 dikes have been built, dividing our study region into 11 zones. The main aim of this study was to evaluate the effects of long-term reclamation on the variability of soil properties. Using an integrated transect and nested sampling approach, a total of 329 surface soil samples were collected. Soil pH, organic matter, electrical conductivity, and particle size distribution were measured. Data were evaluated using classical statistics and geostatistics methods. Results indicate that reclamation exerted quantifiable effects on various soil attributes. There were significant differences in soil properties among the zones. The ranges in semivariograms were approximately equal to or twice the average zone span, suggesting that there was usually a break in continuity of soil properties at the boundary of reclamation zones. As illustrated by the lower nugget effect or larger range distance in semivariograms, soil pH, electrical conductivity, and organic matter similarly showed more continuous patterns in space compared with particle size distribution. With the increase of time since reclamation, salt content, alkalinity, and particle size tended to decrease, while organic matter content tended to increase. Most properties varied greatly in the initial reclamation stages. A relatively steady state was reached within 10 years following the reclamation for pH, about 30 years for organic matter, and 60 years for electrical conductivity, respectively. Further, similar land uses and parent materials produced similar inherent soil properties. These findings can be applied to broader spatial scales in other coastal regions to assist in transitioning from a coastal tidal plain to productive agricultural land, through reclamation, and targeted land management practices.

De Jong, B.; Keijsers, J.G.S.; Riksen, M.J.P.M.; Krol, J., and Slim, P.A., 2014. Soft engineering vs. a dynamic approach in coastal dune management: a case study on the North Sea barrier island of Ameland, The Netherlands.

Dunes act as flood defenses in coastal zones, protecting low-lying interior lands from flooding. To ensure coastal safety, insight is needed on how dunes develop under different types of management. The current study focuses on two types of coastal dune management: (1) a “soft engineering” approach, in which sand fences are placed on the seaward side of foredunes, and (2) “dynamic coastal management,” with minimal or no dune maintenance. The effects of these management styles on dune formation are examined for two adjacent coastal sections of the North Sea barrier island of Ameland, The Netherlands, where dynamic coastal management was introduced in 1995 and 1999, respectively. For each section, we analyzed cross-shore profile data from 1980 until 2010, deriving dune foot position, crest position, crest height, and foredune volume for each year and analyzing the situation before and after the change in management. We further assessed the effect of the management regime on dune vegetation. Other factors that could influence dune development were also taken into account, such as beach width and shape, water levels, wave heights, and nourishments. Results show that implementation of dynamic coastal management did not directly affect the volume of the foredune. Growth was occasionally interrupted, coinciding with high-water events. In periods between erosive storms, dune growth rates did not show a significant difference between management types (p = 0.09 and 0.32 for sections 1 and 2, respectively). The main effect of the change was on vegetation development. Dynamic coastal management, therefore, did not reduce coastal safety.

Klemas, V.; Finkl, C.W., and Kabbara, N., 2014. Remote sensing of soil moisture: an overview in relation to coastal soils.

Soil moisture plays an important role in the exchange of water and heat energy between the land and atmosphere and is used in studies of global climate change. Soil moisture data are also required for reservoir management, early warning of droughts, irrigation scheduling, and crop yield forecasting. Coastal soils in general span the gamut of soil properties necessary for agriculture and maintaining natural environments, including transitional wetlands. Beach characteristics, such as soil moisture, grain size and type, are needed for determining substrate-bearing strength, modeling beach erosion, and planning beach nourishment. Because microwave radiation from soil is strongly dependent on moisture content, soil moisture has traditionally been mapped with airborne microwave radiometers. Innovative antenna technology has enabled microwave radiometers on satellites, such as Soil Moisture and Ocean Salinity and Aqua, to measure soil moisture on a global scale. Better corrections for surface roughness, vegetation cover, soil temperature, and topography must still be devised, and techniques for sensing soil moisture beyond the top few centimeters developed.

Mendoza-González, G.; Luisa Martínez, M., and Lithgow, D., 2014. Biological flora of coastal dunes and wetlands: Canavalia rosea (Sw.) DC.

The genus Canavalia includes 60 species, of which 37 are found in the Neotropics. One of the most common members of this genus is Canavalia rosea. In this paper, we present a compilation of the ecological, physiological, and geomorphological biology of this pantropical beach and coastal dune species that will serve as a basis for scientists and managers interested in the species. This legume (Fabaceae) is a perennial trailing vine that grows on five continents and is also found on many islands. The leaves are compound, and the leaflets are roughly circular in shape, with an entire margin and a short petiole. The flowers are small, pink-purple, in racemes and range from 1 to 3 cm in diameter. Blooming takes place with greatest intensity between May and September, although sporadic racemes can be found throughout the year. Fruits are large, 7–12 cm long, with marbled brown dormant seeds. The root is monopodic and presents a mycorrhizal association. It is a successful colonizer of tropical shorelines due to the dispersal of its seeds by ocean currents and a high tolerance to salt spray, burial, low-nutrient substrates, and high temperature. The species is an important sand colonizer and plays a significant role in the geomorphology of beaches and frontal dunes. The species often covers large areas and forms a relatively continuous mat that stabilizes the sandy substrate in which it grows. The leaves, stems, and seeds have many nutritional and medicinal uses due to their high protein content and active bactericidal ingredients.

El género Canavalia incluye 60 especies de las cuales 37 se encuentran en la región Neotropical. Uno de los miembros más extendidos del género es Canavalia rosea. En este trabajo presentamos una recopilación de la literatura, que no ha sido reunida previamente sobre la biología de esta especie, la cual es importante debido a su amplia distribución en el mundo. Esta leguminosa (Fabaceae) posee una distribución pantropical en las playas arenosas y dunas frontales de los cinco continentes y tiene la habilidad de dispersarse por corrientes marinas. C. rosea posee ramas que pueden medir más de ocho metros de largo, con hojas compuestas y foliolos orbiculares con margen entero y tallo corto. Las inflorescencias son de color rosado o púrpura. La floración ocurre entre mayo y septiembre con mayor intensidad, aunque puede ser esporádica durante el resto del año. Los frutos son vainas de 7–12 cm de largo con semillas latentes, redondas y de color café. La raíz es profunda, monopódica y posee asociaciones micorrícicas. Es una colonizadora exitosa de las costas tropicales gracias a su capacidad de dispersión a larga distancia por medio de las corrientes marinas y a su alta tolerancia al spray salino, al enterramiento y a sustratos con altas temperaturas y bajas cantidades de nutrientes. Esta colonizadora desempeña un papel muy importante en la geomorfología de las playas y dunas frontales ya que es capaz de cubrir grandes áreas y formar tapetes casi continuos que ayudan a fijar la arena y mantienen el sustrato aglutinado. Además, las hojas, tallos y semillas tienen múltiples usos alimenticios y medicinales por su alto contenido en proteínas y principios bactericidas activos.

Kabuth, A.K.; Kroon, A., and Pedersen, J.B.T., 2014. Multidecadal shoreline changes in Denmark.

Multidecadal shoreline changes along ca. 7000 km coastline around Denmark were computed for the time interval between 1862 AD and 2005 AD and were connected with a geomorphological coastal classification. The shoreline data set was based on shoreline positions from historical and modern topographic maps. Coastal landforms were identified on a digital terrain model in combination with aerial photographs. Two shoreline-change computation methods were evaluated at a test site, aiming for optimized time efficiency and accuracy of the countrywide application: a Nearest Neighbor search and a cross-shore transect method based on the ArcGIS-based Digital Shoreline Analysis System (DSAS). The cross-shore transect method was more robust and performed better in the detection of local extremes in shoreline changes, which was crucial for the scope of the mapping. Countrywide shoreline-change distances and rates were, therefore, computed with the DSAS method. Patterns in coastline dynamics were identified through the connection of shoreline-change rates with the occurrence of coastal landforms. Short-term changes and alterations of shoreline evolution through coastal structures were not resolved in this study. Because of the long time span covered, the relative errors originating from data and method are acceptable. The scope of the mapping was to provide a coastal management tool that allows screening for critical sites with respect to coastal erosion. As the first countrywide quantification of historical shoreline changes around Denmark, the mapping can contribute to enhanced adaptation and mitigation strategies in response to increased risks of erosion and flooding under a changing climate.

Anderson, T.R. and Frazer, L.N., 2014. Toward parsimony in shoreline change prediction (III): B-splines and noise handling.

The traditional single-transect method for predicting long-term shoreline change uses far more parameters than necessary because it assumes that erosion/accretion (change) rates at adjacent alongshore positions (transects) are independent. Such overfitting can cause poor predictions of future shoreline location, so recent work has modeled change rates as linear sums of polynomials, or linear sums of principal components. Here we introduce an alternative method that uses linear sums of B-splines. As in earlier work, an information criterion is used to identify the optimal number of basis functions. The local nature of B-spline models makes them less susceptible to the Gibbs effect than polynomial models, and their smoothness makes them more robust to noise than principal components regression. We also compare three noise-handling techniques by examining their effects on the posterior probability density functions of rates. We find that noise handling affects both predicted rate and its uncertainty, and that correlated noise is best addressed by iteratively constructing a full covariance matrix from data residuals. We illustrate our procedure using synthetic data and shoreline data from Assateague Island and Ocean City, Maryland.

Mattheus, C.R., 2014. Climate-induced changes in rates of headland-beach progradation along the southern coast of Lake Erie.

Isolated portions of the sediment-starved U.S. Lake Erie coast have prograded over the last 100 years in response to littoral drift disruption by hard-structure installation. Published nautical charts offer insight into decadal-scale sediment dynamics operating around this erosional coastline's prograding headland beaches. Nearshore-surface models constructed from historical bathymetry data sets show that headland-beach progradation occurs with little change in shoreface-profile shape; beach-area gain therefore provides a metric for sediment-volume change. A time-series analysis of beach growth, lake level, drought occurrence, and winter-ice cover suggests that headland geomorphology is partly climate driven. Decreased rates of beach progradation experienced along studied headlands between the late 1930s and early 1950s followed extreme drought conditions, exceptionally low lake levels, and low winter-ice covers. Reduced sediment supply to headland beaches is inferred by hampered bluff erosion during periods of low lake level, affiliated with less direct wave impact on bluffs, and drought conditions, associated with reduced groundwater-related mass wasting of bluffs. Similar drought and low-lake-level conditions existed throughout the 1960s; however, this period experienced high winter-ice covers and was unaffiliated with a change in headland-beach progradation rate, likely due to diminished sediment losses from adjacent nearshore regions during winter seasons. Reduced bluff erosion of the 1930s was induced by a combination of low lake levels and drought conditions and, along with nearshore-sediment losses in absence of winter-ice cover, stunted headland-beach growth during the subsequent period of lake-level rise. A decadal delay of headland-shoreline response to these climate extremes attests to the nearshore system's poor buffering capacity to environmental changes altering sediment availability.

Bolca, M.; Özen, F., and Güneş, A., 2014. Land use changes in Gediz Delta (Turkey) and their negative impacts on wetland habitats.

In this research, we investigate Izmir Bird Paradise, which is located on the coast of Gediz Delta (Turkey) and is protected via the Convention on Wetlands of International Importance, Especially as Waterfowl Habitat (International Ramsar Agreement). We determined land use changes in salty–alkali areas and changes in biological habitats by using remote sensing techniques and geographic information systems (GIS). We determined temporal changes in different types of land by using 1/20,000 scaled aerial photos of the research area from 1963 and 1996 and Quickbird satellite images with 61-cm resolution from 2005 and 2010. We noted existing biological changes in the same period by associating them with different land use types. At the end of the research, we studied changes to biological habitats in wetlands in coastal Gediz Delta due to the pressures of urban and industrial settlements and agricultural areas. According to the data, between 1963 and 2010 there was a ∼84.40% increase in urban–industrial settlements, a ∼13.74% increase in agricultural areas, and a ∼65.59% increase in saltpan areas. On the other hand, there was a ∼37.65% decrease in habitat and nutrition areas of biological variations (bird habitat, wetland flora, and fauna), a ∼41.54% decrease in coastal–sand dune–salty alkali areas, and a ∼30.63% decrease in swamp and wetland areas. As a result of these changes, numerous species in the wetlands have died or decreased.

Liu, B.; Jeng, D.S., and Zhang, J.S., 2014. Dynamic response in a porous seabed of finite depth to combined wave and current loadings.

In this study a u-p approximation for the dynamic response of a porous seabed to nature dynamic loadings is proposed. Unlike most previous research, the effects of currents are considered in the new analytical solution. Based on the numerical examples, the significant influence of combined wave and current loadings on seabed response in shallow water is concluded. This influence affects not only the amplitudes of the seabed response but also the distributions of the space region. The relative difference of the maximum pore pressure between different direction currents can reach 8% of the static water pressure. In addition, the relative difference of maximum liquefaction depth between the previous model (without currents) and the present model can reach 19% of the maximum liquefaction depth of the case without currents.

Kocum, E. and Sutcu, A., 2014. Analysis of variations in phytoplankton community size-structure along a coastal trophic gradient.

The phytoplankton community size structure is a significant factor in the ecological and biogeochemical functioning of marine ecosystems. Various environmental factors, including nutrients, can cause variations in the size structure of phytoplankton community, ultimately determining the potential for downward carbon transport and productivity in marine ecosystems. In the present study, microscale spatial variation in phytoplankton size structure was investigated at two coastal stations having different nutrient environments. The variation in phytoplankton size structure was characterized by a significantly (p < 0.05) higher contribution of larger cells and diminishing abundance of picoplankton under increasing nutrient concentrations observed at both sites, although at different threshold unfractionated phytoplankton chlorophyll a biomass levels. The average percent contributions of picoplankton to total biomass were 30.02 and 19.07% at less enriched site I and at enriched site II, respectively. Thus, we concluded that the variation in phytoplankton size structure was led by the factors that regulated the contribution of large phytoplankton cells; that is, the dominance of picoplankton was only possible when nutrient concentrations precluded accumulation of the larger size classes in the phytoplankton community.

Bu çalışmada Çanakkale Boğazı kıyılarında trofik bakımdan farklılık gösteren iki bölgede fitoplankton komünitesi büyüklük yapısındaki değişim incelenmiştir. Nutrient bakımından zengin bölgede ve toplam fitoplankton biyokütlesi arttığında ise her iki bölgede fitoplankton komünitesindeki büyük hücreli üyelerin bolluğunda artma ve pikoplankton bolluğunda da düşüş gözlemlenmiştir. Çalışma sonucunda fitoplankton komünitesi büyüklük yapısındaki varyasyonun büyük hücreli üyelerin artışını engelleyen koşullarca düzenlendiği yani, pikoplankton bolluğundaki artışın ancak büyük hücreli fitoplankton artışını sınırlayan nutrient yoğunluklarında meydana geldiği ileri sürülmüştür.

Venekey, V.; Santos, P.J.P., and Fonsêca-Genevois, V.G., 2014. Effect of environmental factors on intertidal Nematoda in a tropical sandy beach (Tamandaré Bay, Pernambuco, Brazil).

The present study describes spatial and temporal variation patterns of nematode assemblages in a tropical sandy beach (Tamandaré, in the state of Pernambuco, Brazil) and associates them with environmental factors (granulometry, chlorophyll-a, phaeopigments, organic matter, temperature, salinity, monthly rainfall, and wind velocity), testing the main hypothesis that these assemblages are influenced by seasonal variations even in areas where seasons of the year are not distinct. The Nematoda assemblage varied significantly across seasons (spring, summer, autumn, and winter) and between sampling stations (upper intertidal and lower intertidal) and sediment layers (0–10 and 10–20 cm). These differences were associated mainly with the variations of Calomicrolaimus formosus, dominant species of the nematode assemblage composed mainly of epistrate feeders. Diversity and evenness did not vary significantly in any situation, and richness was significantly higher in the lower intertidal area. None of the environmental factors were identified as the main structuring agent of the nematode assemblage, suggesting seasonality (or a group of factors that have seasonal variations, mainly rainfall) as the major influence. A sampling scheme considering four seasons for future temporal studies is recommended, including studies in tropical regions.

O presente estudo descreve os padrões de variação das assembleias de nematódeos numa praia arenosa tropical (Tamandaré, no estado de Pernambuco, Brasil) e associa-os aos fatores ambientais (granulometria, clorofila-a, feopigmentos, matéria orgânica, temperatura, salinidade, pluviosidade mensal, e velocidade do vento), testando a hipótese principal de que essas assembleias são influenciadas pelas variações sazonais mesmo em áreas onde as estações do ano não são distintas. A assembleia de Nematoda variou significativamente entre estações (primavera, verão, outono, e inverno) e entre locais de coleta (médiolitoral superior e médiolitoral inferior) e estratos sedimentares (0–10 e 10–20 cm). Essas diferenças estiveram associadas principalmente às variações de Calomicrolaimus formosus, espécie dominante da assembleia de Nematoda composta principalmente de comedores de epistrato. Diversidade e equitatividade não variaram significativamente em nenhuma das situações, e riqueza foi significativamente maior no médiolitoral inferior. Nenhum dos fatores ambientais foi determinado como o estruturador principal da assembleia de Nematoda, sugerindo a sazonalidade (ou o grupo de fatores que tem variação sazonal, principalmente pluviosidade mensal) como a maior influência. Um esquema de coleta considerando quatro estações é recomendado para futuros estudos temporais, mesmo em regiões tropicais.

Miller, E.F., 2014. Description of conditions preceding the 2011 Redondo Beach, California, fish kill.

On 8 March 2011, hypoxic conditions resulted in the loss of ca. 1.5 million Sardinops sagax in King Harbor, Redondo Beach, California. Uncertainty remains regarding the school's entrance into the harbor and the hydrographic conditions leading up to the event. Unusually depressed dissolved oxygen concentrations and acidic pH at 4–7 m depth in the main channel of the harbor were recorded on February 22 during permit-required power plant discharge monitoring. Similarly minimal tidal amplitude occurred on 22 February and 8 March, resulting in minimal seawater exchange within the harbor. Power plant impingement surveys at the nearby generating station began observing S. sagax in January, with an order of magnitude more individuals impinged on 3 February than any prior 24-hour survey and continued impingement occurring at above average levels through February. The data suggested the school entered in late January and might have remained through February at depth. When the 8 March neap tide occurred, hypoxic conditions developed in Basin 1, the most secluded basin, leading to the fish kill.

Chaichitehrani, N.; D'Sa, E.J.; Ko, D.S.; Walker, N.D.; Osburn, C.L., and Chen, R.F., 2014. Colored dissolved organic matter dynamics in the Northern Gulf of Mexico from ocean color and numerical model results.

Colored dissolved organic matter (CDOM) absorption and salinity relationships were assessed and used in conjunction with the salinity and current outputs of a numerical model (Navy Coastal Ocean Model [NCOM]) to study CDOM dynamics in the northern Gulf of Mexico. In situ CDOM absorption and salinity obtained from multiple field campaigns were inversely correlated seasonally (winter–spring and summer) and latitudinally (inner- and outer-shelf zones), suggesting conservative behavior of CDOM distribution. A weaker correlation, during summer in the outer-shelf zone, however, indicated stronger effects of photooxidation and lower masking effects from riverine CDOM. Applying these relationships to simulated salinity resulted in hourly maps of CDOM that revealed similarities to CDOM patterns derived from SeaWiFS satellite imagery. Further, matchup comparisons between model-derived and in situ CDOM absorption were statistically sound for the summer (bias = −0.016, root mean square error = 0.059, r² = 0.51 SI = 0.28) and the winter–spring periods (bias = 0.033, root mean square error = 0.099, r² = 0.52, SI = 0.21). Overlaying the model-derived CDOM maps on the simulated currents revealed the strong influence of currents on CDOM advection. Downcoast currents during the nonsummer months led to persistent advection of CDOM westward interrupted by frequent cold front events that flush CDOM-laden waters out of the coastal bays onto the inner and outer continental shelves. In contrast, the upcoast current regime, though less well organized, produces a more significant seaward advection of CDOM, likely due to the Ekman transport and subsequent entrainment by mesoscale eddies over the continental slope.

Murren, C.J.; Purvis, K.G.; Glasgow, D.; Messervy, J.; Penrod, M., and Strand, A.E., 2014. Investigating lag phase and invasion potential of Vitex rotundifolia: a coastal dune exotic.

After initial establishment in nonnative environments, exotic species are often found in low numbers for long periods of time. After a lag phase, a transition to an exponential growth phase is characteristic. A broad question remains: Can we identify factors that contribute to the lag phase or assess the potential for additional invasion? Our approach employed a case study of V. rotundifolia (beach vitex), a nonnative dune plant introduced in the late 1980s to North and South Carolina. We performed manipulative and observational experiments on the sexual and asexual reproductive ecology, mating system, seed ecology, and pollination ecology to assess the possibility of additional invasion potential and to gain an understanding of potential among population variation and among site ecological variation that could contribute to a transition from lag to exponential spread phases. We found that vegetative reproduction, sexual reproduction, and viable seed set rates are high, and there is future potential for spread through vegetative reproduction as not all the ovules set seed. Pollinator activity varied by year and was consistent with increased fruit and seed set, indicating a likely mechanism contributing to current sexual reproductive success. Germination rate was low, but given the high numbers of seeds produced per square meter, we estimate an average of 13 new germinants m⁻² y⁻¹. On the basis of our observations, we found the potential for increased reproductive success and increased invasion potential. Management practices that minimize vegetative expansion from nearby sites and through seed dispersal are the highest priority.

Pechsiri, J.S.; Risén, E.; Malmström, M.E.; Brandt, N., and Gröndahl, F., 2014. Harvesting of Nodularia spumigena in the Baltic Sea: assessment of potentials and added benefits.

Interest to harvest wild cyanobacteria exists due to the environmental and socioeconomic risks during cyanobacteria blooms coupled with demands for nonterrestrial-based alternatives for biofuel sources. This research, therefore, sought to estimate the wild cyanobacteria harvesting potential using Nodularia spumigena, and using the Baltic Sea as the case study. Data from literature provided during years 2003–2009 were used to perform estimations. Additional benefits of harvesting were also assessed by estimating the nutrient removal and biogas production potentials from the harvested biomass. Results indicate that one boom unit has the potential to harvest approximately 3 to 700 kg dry weight of N. spumigena per hour depending on the algae concentration of the bloom. Results also suggest that nutrient removal and biogas production potentials provide substantial additional incentives to the harvesting operation during years of extensive and highly concentrated blooms. However, during nonextensive or nonconcentrated blooms such potentials are low.

Intresset för skörd av cyanobakterieblomningar beror på de miljö- och socio-ekonomiska risker som blomningarna medför. Ytterligare en bidragande orsak till detta intresse är efterfrågan efter icke markbaserade biobränslealternativ. Denna studie ämnar därför att undersöka potentialen med skörd av vilt förekommande cyanobakterieblomningar med arten Nodularia spumigena och Östersjön som fallstudie. Litteraturdata från åren 2003–2009 användes för att kvantifiera blomningarna. Ytterligare fördelar med skörden utvärderades också genom en uppskattning av näringsreduktionens och biogasproduktions potentialen av den skördade biomassan. Resultat indikerar att en skördeenhet har potentialen att skörda uppskattningsvis 3 till 700 kg ts Nodularia spumigena per timme beroende på algblomningens koncentration. Resultaten indikerar dessutom att näringsreduktionsförmågan och biogasproduktionspotentialen tillhandahåller ytterligare substantiella incitament för skörd under år med omfattande och koncentrerade blomningar. Dessa ytterligare incitament är dock inte betydande under de år då blomningarna inte är omfattande och koncentrerade.

Pintó, J.; Martí, C., and Fraguell, R.M., 2014. Assessing current conditions of coastal dune systems of Mediterranean developed shores.

A method of assessment was developed to evaluate the current condition and function of dunes in developed coastal tourist areas of the Mediterranean. The aim was to identify a procedure for differentiating between more and less valuable dune systems. The method was tested on the Costa Brava (Catalonia, NE Spain) and may prove useful for designing conservation and management strategies for coastal dunes in developed areas. The evaluation method was based on a set of 12 indicators relating to three aspects that we consider fundamental for the management of dune landscapes: dune morphology (dune landforms) associated with the evolution of the dune system, dune vegetation, and human impacts. The assessment was tested on each of the 34 existing dune systems of the Costa Brava. Cluster analysis provided a classification into five groups differentiated by characteristics of morphological development, total number of dune-restricted plant species, and degree of human impact suffered. The best evaluation was achieved by the indicators of morphological development, with 76% of the dune systems rating above average. On the other hand, only 42% of the systems rated above average in the indicator of dune-restricted plant species. The worst results came from the indicators of human impact, with only three beaches rating above average in this respect. The evaluation has shown the Costa Brava dune systems to be in a precarious state of conservation because most systems are located on urban or suburban beaches. The best-conserved areas were the larger dune systems located on seminatural or semiurban beaches, where human pressure is weaker. The procedure described in this article provides a useful tool for coastal managers to assess changes in the state of their dune systems over time and to focus their management policies on the protection of systems under the greatest threat.

En este trabajo se presenta un método de evaluación del estado actual de los sistemas dunares que se localizan en las costas mediterráneas de uso turístico. El método está basado en la utilización de 12 indicadores relacionados con los elementos más significativos del medio ambiente dunar: el desarrollo morfológico de las dunas, la vegetación que albergan y los impactos humanos que afectan al sistema. La bondad del índice ha sido testada en los 34 sistemas dunares identificados en la Costa Brava (NE Spain), una de las principales costas turísticas del Mediterráneo occidental. Un análisis de grupos ha permitido la clasificación de de los sistemas dunares estudiados en cinco grupos, que se diferencian en el desarrollo morfológico, la diversidad de especies y la intensidad del impacto humano. Los mejores resultados fueron obtenidos por los indicadores sobre la morfología de las dunas, con un 76% de los sistemas por encima del valor medio. Por otro lado, solo el 42% de los sistemas dunares superó el valor medio del indicador de diversidad de especies. Los peores resultados fueron para los indicadores relacionados con el impacto humano, con solo tres playas por encima de la media. La evaluación ha mostrado que los sistemas dunares de la Costa Brava se encuentran en un estado precario, ya que la mayoría se localizan en playas urbanas y suburbanas. Los sistemas mejor conservados son los situados en playas naturales y seminaturales donde la presión humana es menor. El procedimiento utilizado proporciona una herramienta útil para los gestores de la costa en la evaluación de los cambios en el estado de los sistemas dunares en el tiempo y en dirigir la gestión en la protección de los sistemas más amenazados.

Bissett, S.N.; Zinnert, J.C., and Young, D.R., 2014. Linking habitat with associations of woody vegetation and vines on two mid-Atlantic barrier islands.

Coastal habitats are inherently vulnerable to global change, as they are the first areas impacted by sea level rise and to experience more frequent and intense storms. Shrubs and vines dominate the climax communities in these environments, and with comparatively long regeneration periods, they are highly vulnerable to shifting topography and climate. We investigated abiotic and biotic components of two barrier island landscapes with similar plant communities but different site histories to clarify relationships among physical factors, woody plants, and vines. On Hog Island, Virginia and at Duck, North Carolina, intrasite comparisons with reference to distance from shoreline and elevation were made to evaluate relationships between woody and vine communities, as well as edaphic characteristics. Elevation was significantly related to woody species presence, and vine presence was significantly related to presence of woody structure, indicating an indirect association of the climbing species to elevation. Differing histories of management and development at the two sites have resulted in varying degrees of both topographic complexity and stability. Greater topographic complexity has resulted in similar species richness values for the two sites, despite the considerable difference in total area. Presumably, stabilization and prior management efforts at the Duck site have enabled a community assemblage comparable to that of the much larger Hog Island; however, the Duck site may be more vulnerable because of a decreased potential to migrate in response to continued sea level rise and storm impacts.

Liang, S.; Sun, Z.; Sun, J., and Zhang, Z., 2014. Study on the erosion mechanism of the Bijia Mountain gravel tombolo, China.

We investigated the mechanism of erosion on Bijia Mountain tombolo, a famous gravel tombolo in China. Both numerical simulation and experiment were carried out. First, the mechanism was deduced by reviewing changes in cross section, crest elevation, gravel composition, and overall shape in the tombolo between 1985 and 2005 and changes in wave condition near the tombolo. Then, an overall physical model test was carried out to verify this mechanism. Based on the experimental data, we conclude that the breaking of original balanced wave conditions is the main reason for the erosion. When the bidirectional alternating wave action changed into a unidirectional wave field, the original equilibrium was broken. Strong easterly waves (over 25 and 50 year return periods) eroded the tombolo, while wave effects from the ESE and SE directions at mean water level were the main causes of the tombolo's destruction, followed by wave effects from the E direction. The main effects of the waves decreased the height and skewed the cross section. The strong erosion happened at mean water level, where the waves broke near the top and induced stronger current. The positions of the troughs had a good relationship to the wave-energy distribution. Further study was performed by cross-sectional model test to check out the effects of current on the deep trough along the tombolo. The tombolo was severely eroded due to the joint effects of eastward waves and tidal currents. This investigation on the mechanism of the erosion of Bijia Mountain tombolo can be used in further studies of the restoration of the tombolo.

Timm, B.C.; Smith, S.M., and Greenspan, S.E., 2014. Remotely sensed mapping of Ammophila spp. distribution and density at Cape Cod National Seashore.

Ammophila breviligulata and Ammophila arenaria are pioneer grass species that have been planted within and outside their natural ranges in efforts to stabilize mobile dune fields. While the presence of Ammophila spp. may be considered beneficial in some situations (e.g., for dune stabilization and storm surge protection), there are other cases where Ammophila spp. introductions have had negative ecological consequences (e.g., reduction in native plant and animal diversity, altered dune dynamics). Thus, it is important to be able to effectively map and monitor the distribution and density of these species. In this study, we constructed and assessed the accuracy of a fine-resolution (i.e. 1.0-m-pixel resolution) remote-sensing-based distribution and density map of Ammophila spp. throughout an extensive coastal dune ecosystem at Cape Cod National Seashore, United States. We achieved high classification accuracies for both the presence/absence and percent cover throughout our study area, indicating that this approach is an effective method to map and monitor Ammophila spp. in dune ecosystems.