Coastal marshes Research Papers - Academia.edu (original) (raw)

• Mediterranean marshes are highly diverse in macroalgae despite high nitrogen levels • Macroalgal assemblages can be used to evaluate ecological quality of Mediterranean marshes • These systems are severely threatened by human activities... more

• Mediterranean marshes are highly diverse in macroalgae despite high nitrogen levels • Macroalgal assemblages can be used to evaluate ecological quality of Mediterranean marshes • These systems are severely threatened by human activities and climate change • Mediterranean marshes deserve to be protected and better studied as sentinels of climate change a b s t r a c t Although Mediterranean marshes have historically suffered high anthropogenic pressure, they have maintained their remarkable biodiversity. They are severely threatened but remain comparatively unexplored systems from the algological point of view. For example, most of the indexes proposed for monitoring ecological quality are based on diatoms and very few have explored the use of macroalgae. The Pego-Oliva marsh is located in the east of the Iberian Peninsula close to the Mediterranean coast with warm annual temperature and fairly high precipitation. The aims of this study were to ascertain the ecological variables that explained macroalgal distribution in the Pego-Oliva marsh and to assess their indicator value. Macroalgal biodiversity was seen to be high (50 taxa) despite the high nitrogen concentration of the marsh. All the environmental variables studied had a broad range of variation throughout the marsh, especially conductivity (500–12290 μS/cm), temperature (14.3–31.7°C), nitrate (9.493–64.113 mg/L) and ammonium (0.004–0.814 mg/L). A clear gradient of conductivity and dissolved oxygen was observed from fresh to saltwater. Batrachospermum arcuatum, Calothrix parietina, Chaetophora tuberculosa, Draparnaldia mutabilis, Hildenbrandia angolensis and Leptolyngbya angustissima were seen to act as indicators of low conductivity and dissolved inorganic nitrogen, and high dissolved oxygen, while Calothrix pulvinata, Ulva intestinalis, Homoeothrix violacea, Phormidium tergestinum and Thorea violacea were indicators of high conductivity and low dissolved nitrogen habitats. Cladophora glomerata, Compsopogon coeruleus, Polysiphonia subtilissima and Ulva flexuosa are the most widespread species and have a broad ecological range. Irrigation ditches have high ammonium and low dissolved oxygen concentrations and host infrequently reported species like Kumanoa mahlacensis. The data presented confirm the usefulness of macroalgae for the ecological monitoring of marshes, while increasing our knowledge of the distribution and ecological range of some species. However, more experimental work is needed to know the tolerance range of species living in dynamic systems like Mediterranean marshes.

Les jeunes filles nues assises font partie de la «mise en scène» du mobilier funéraire qui accompagne notamment les enfants et les jeunes filles. Nous prendrons comme exemple les cas où le contexte est donné, comme à Abdère, à... more

Les jeunes filles nues assises font partie de la «mise en scène» du mobilier funéraire qui accompagne notamment les enfants et les jeunes filles. Nous prendrons comme exemple les cas où le contexte est donné, comme à Abdère, à Amphipolis, à Thasos, à Samothrace, à Béroia, à Pella, et des cas où il reste problématique, comme à Myrina, à Délos ou ailleurs. Peut-on interpréter ces figurines comme des «hierodouloi», comme soutenu dans la bibliographie récente ? Ou s’agit-il de jeunes femmes désirables à la fleur de l’âge pratiquant des rituels suggérés par les sources écrites et figurées, ainsi que par le reste du mobilier et en comparaison avec le matériel votif ?
Les figurines en terre cuite appartiennent à la fois au monde votif et au monde funéraire. Si le monde votif rend l’interprétation relativement plus aisée à cause du contexte donné, le monde funéraire offre d’autres dimensions à leur compréhension, grâce au contexte individualisé de la sépulture. Nous avons pu démontrer que le mobilier de cette dernière constitue un langage qui se construit selon le mode de l’image et se réfère la plupart du temps au mort précis, puisque les objets choisis et déposés près de son corps présentent des régularités. Celles-ci ne s’expliquent que par des choix correspondant à des actes intentionnels pratiqués pendant les rituels funéraires. Aussi, le simple inventaire et les statistiques concernant les occurrences des différentes catégories de ktérismata, et des figurines en particulier, que nous rencontrons dans la plupart des études, ne sauraient pas nous conduire à saisir les liens entre rites funéraires et religieux et encore moins à comprendre la fonction des terres cuites à l’intérieur de la sépulture.

Siden krigen mod Irak blev indledt i marts 2003, har aviserne vaere fulde af historier om Saddam Husseins uhyrligheder. Et eksempel herpa er odelaeggelsen af Iraks marskomrader, der har haft katastrofale konsekvenser for savel menneskeliv... more

Siden krigen mod Irak blev indledt i marts 2003, har aviserne vaere fulde af historier om Saddam Husseins uhyrligheder. Et eksempel herpa er odelaeggelsen af Iraks marskomrader, der har haft katastrofale konsekvenser for savel menneskeliv som omradets rige dyreliv. Mens ansvaret for overgreb pa befolkningen er Saddam Husseins, skyldes udtorringen af marsksystemet en raekke hydro-politiske beslutninger, som er blevet taget i hele Eufrat og Tigris’ opland. Artiklen viser, hvordan diskurserne om odelaeggelsen af marsken har aendret sig efter krigen, og at de er blevet brugt til at legitimere krigen. Dette har givet et forsimplet billede af savel marskomraderne som marskarabernes levevis. Det konkluderes, at det er nodvendigt med en mere nuanceret forstaelse af de problemer, der forte til denne humane og okologiske katastrofe, hvis naturgenopretningen og repatrieringen af marskaraberne skal have en chance.

The increasing rate of sea level rise (SLR) poses a major threat to coastal lands and natural resources, especially affecting natural preserves and protected areas along the coast. These impacts are likely to exacerbate when combined with... more

The increasing rate of sea level rise (SLR) poses a major threat to coastal lands and natural resources, especially affecting natural preserves and protected areas along the coast. These impacts are likely to exacerbate when combined with storm surges. It is also expected that SLR will cause spatial reduction and migration of coastal wetland and marsh ecosystems, which are common in the natural preserves. This study evaluates the potential impacts of SLR and marsh migration on the hydrodynamics and waves conditions inside natural protected areas during storm surge. The study focused on four protected areas located in different areas of the Chesapeake Bay representing different hydrodynamic regimes. Historical and synthetic storms are simulated using a coupled storm surge (ADCIRC) and wave (SWAN) model for the Bay region for current condition and future scenarios. The future scenarios include different rates of local SLR projections (0.48 m, 0.97 m, 1.68 m, and 2.31 m) and potential land use changes due to SLR driven marsh migration, which is discretized in the selected preserve areas in a coarse scale. The results showed a linear increase of maximum water depth with respect to SLR inside the protected areas. However, the inundation extent, the maximum wave heights, and the current velocities inside the coastal protected areas showed a non-linear relationship with SLR, indicating that the combined impacts of storm surge, SLR, and marsh migration depend on multiple factors such as storm track, intensity, local topography, and locations of coastal protected areas. Furthermore, the impacts of SLR were significantly greater after a 1 m threshold of rise, suggesting the presence of a critical limit for conservation strategies.

Many factors, such as rising sea levels and human alterations, threaten coastal wetlands in the United States and around the world. To reverse some wetland loss, dredge material, tidal flow, or river flow can be used to create new... more

Many factors, such as rising sea levels and human alterations, threaten coastal wetlands in the United States and around the world. To reverse some wetland loss, dredge material, tidal flow, or river flow can be used to create new wetlands or existing wetlands can be managed to increase plant productivity. Identifying the causes of limited production can improve management plans by suggesting possible remedies. Managing and restoring marshes depends on understanding which stress factors limit growth of key marsh-building plants. Spartina patens is a common marsh-building species of grass in brackish marshes along the Gulf of Mexico and Atlantic coasts of North America and it is often the target of management and restoration plans. S. patens was grown under six flooding levels in a field experiment. S. patens plants grown at lower elevations had consistently lower biomass, in contrast to S. alterniflora, which has been shown to exhibit peak biomass at intermediate levels of flooding. Critical values of elemental concentrations in plant tissue are widely used to diagnose mineral deficiencies in agricultural crops and are just beginning to be developed aid wetland management and restoration. For leaf tissue harvested in summer, [Mn] < 256 ppm and [Ca] < 0.3% indicated that plants grew at lower elevations and had limited biomass. The results suggest that concentrations of Mn and Ca in the leaf tissue of S. patens could form part of an indicator to monitor below-ground productivity of marshes. Although low concentrations of these elements were associated with the smaller root and shoot biomass of plants grown at low elevations, variability in the relationship suggests that additional factors may need to be considered. Marsh managers should monitor soil elevation loss carefully if they choose to drain marshes to increase plant production to prevent excessive loss of soil elevation.

In the aftermath of the 2003 war against Iraq, the newspapers are full of stories about the monstrosities of Saddam Hussein’s regime. One example is the destruction of the Iraqi marshlands leading to severe consequences for the human... more

In the aftermath of the 2003 war against Iraq, the newspapers are full of stories about the
monstrosities of Saddam Hussein’s regime. One example is the destruction of the Iraqi
marshlands leading to severe consequences for the human and wildlife population. While the
responsibility for the atrocity against the Marsh Arabs is Saddam Hussein’s, the desiccation of the
marsh environment can be ascribed to a number of the hydro-political decisions made in the
catchment area of the Euphrates and Tigris Rivers. Based on an analysis of the discourses of the
destruction, it is demonstrated how these have changed after the war and are used in the battle to
legitimise the war. This has led to a simplified image of the marshes and the Marsh Arab way of
life. As the paper shows, a more complex approach towards the processes leading to this human
and environmental disaster is required, if repatriation and rehabilitation of the area are to stand a
chance.

• Anthropogenic disturbances have resulted in massive seagrass die-off. • Loss of seagrasses has resulted in organic carbon flux. • The magnitude of organic carbon loss depends on the type of seagrass disturbance. • Seagrass restoration... more

• Anthropogenic disturbances have resulted in massive seagrass die-off. • Loss of seagrasses has resulted in organic carbon flux. • The magnitude of organic carbon loss depends on the type of seagrass disturbance. • Seagrass restoration has the potential to reverse seagrass sedimentary C losses. Seagrasses comprise a substantive North American and Caribbean Sea blue carbon sink. Yet fine-scale estimates of seagrass carbon stocks, fluxes from anthropogenic disturbances, and potential gains in sedimentary carbon from seagrass restoration are lacking for most of the Western Hemisphere. To begin to fill this knowledge gap in the subtropics and tropics, we quantified organic carbon (C org) stocks, losses, and gains from restorations at 8 previously-disturbed seagrass sites around the Gulf of Mexico (GoM) (n = 128 cores). Mean natural seagrass C org stocks were 25.7 ± 6.7 Mg C org ha −1 around the GoM, while mean C org stocks at adjacent barren sites that had previously hosted seagrass were 17.8 Mg C org ha −1. Restored seagrass beds contained a mean of 38.7 ± 13.1 Mg C org ha −1. Mean C org losses differed by anthropogenic impact type, but averaged 20.98 ± 7.14 Mg C org ha −1. C org gains from seagrass restoration averaged 20.96 ± 8.59 Mg ha −1. These results, when combined with the similarity between natural and restored C org content, highlight the potential of seagrass restoration for mitigating seagrass C org losses from prior impact events. Our GoM basin-wide estimates of natural C org totaled ~36.4 Tg for the 947,327 ha for the USA-GoM. Including Mexico, the total basin contained an estimated 37.2-37.5 Tg C org. Regional US-GoM losses totaled 21.69 Tg C org. C org losses differed significantly among anthro-pogenic impacts. Yet, seagrass restoration appears to be an important climate change mitigation strategy that could be implemented elsewhere throughout the tropics and subtropics.

Seagrasses comprise a substantive North American and Caribbean Sea blue carbon sink. Yet fine-scale estimates of seagrass carbon stocks, fluxes from anthropogenic disturbances, and potential gains in sedimentary carbon from seagrass... more

Seagrasses comprise a substantive North American and Caribbean Sea blue carbon sink. Yet fine-scale estimates of seagrass carbon stocks, fluxes from anthropogenic disturbances, and potential gains in sedimentary carbon from seagrass restoration are lacking for most of the Western Hemisphere. To begin to fill this knowledge gap in the subtropics and tropics, we quantified organic carbon (Corg) stocks, losses, and gains from restorations at 8 previously-disturbed seagrass sites around the Gulf of Mexico (GoM) (n=128 cores). Mean natural seagrass Corg stocks were 25.7±6.7MgCorgha(-1) around the GoM, while mean Corg stocks at adjacent barren sites that had previously hosted seagrass were 17.8MgCorgha(-1). Restored seagrass beds contained a mean of 38.7±13.1MgCorgha(-1). Mean Corg losses differed by anthropogenic impact type, but averaged 20.98±7.14MgCorgha(-1). Corg gains from seagrass restoration averaged 20.96±8.59Mgha(-1). These results, when combined with the similarity between natu...

Le but de cet article est de faire la caractérisation et l’analyse du contexte au sein duquel se déroulent, depuis la fin des années 80, la restauration et la mise en valeur patrimoniale des Marais de Santoña, Victoria et Joyel, situés... more

Le but de cet article est de faire la caractérisation et l’analyse du contexte au sein duquel se déroulent, depuis la fin des années 80, la restauration et la mise en valeur patrimoniale des Marais de Santoña, Victoria et Joyel, situés sur le littoral oriental de la communauté autonome de Cantabrie et qui constituent la plus vaste zone humide et l’un des écosystèmes le plus importants du nord de l’Espagne. Cet Espace naturel occupe actuellement plus de 6.600 ha répartis sur onze municipalités. Son processus de patrimonialisation apparait très lié à celui de sa protection et de sa restauration écologique, entamées à la fin des années 80. Pourtant cette évolution a eu lieu dans un contexte assez polémique, entrainant des conflits récurrents entre les différents agents impliqués.

Fundulus grandis (Baird and Girard), the Gulf Killifish, is an abundant species throughout the marshes of the northern Gulf of Mexico. Its wide distribution and high site fidelity makes it an ideal indicator species for brackish and salt... more

Fundulus grandis (Baird and Girard), the Gulf Killifish, is an abundant species throughout the marshes of the northern Gulf of Mexico. Its wide distribution and high site fidelity makes it an ideal indicator species for brackish and salt marshes, which experience a variety of anthropogenic disturbances. Despite the ecological, commercial, and scientific importance of F. grandis, age determination methods have not been validated and little is known of its growth pattern. By combining a tag-recapture study with a chemical marker to stain otoliths, we validated an ageing method for F. grandis adults (49–128 mm TL) using whole sagittal otoliths and determined growth rates of recaptured individuals in winter (n = 58) and summer (n = 36) in Louisiana. Mean somatic growth in length was significantly greater during the winter (0.085 mm d−1) than summer (0.054 mm d−1). In contrast, mean otolith growth was significantly greater in summer (1.37 μm d−1) than winter (0.826 μm d−1). The uncoupling of somatic and otolith growth may be primarily attributed to warm summer temperatures, which led to enhanced otolith growth while simultaneously reducing somatic growth. Fundulus grandis was aged to a maximum of 2.25 years. The parameters of the von Bertalanffy growth model were estimated as: L∞ = 87.27 mm, k = 2.43 year−1, and t0 = −0.022. These findings reveal essential age and growth information for F. grandis and provide a benchmark to evaluate responses to environmental disturbances.

The Lucanian Ionian coast represents an interesting case of transformation of the agrarian landscape affected by Greek colonisation, followed by the Roman conquest, then the monastic communities of the Middle Ages, and finally threatened... more

The Lucanian Ionian coast represents an interesting case of transformation of the agrarian landscape affected by Greek colonisation, followed by the Roman conquest, then the monastic communities of the Middle Ages, and finally threatened by the Saracen invasions. In the eighteenth century the area was divided into an internal hilly area in which the characteristic landscape was dominated by grassland and cereal crops, and near the cities vineyards, olive groves, orchards and woods prevailed. On the plains towards the coast, in the many water basins, cereals with vineyards and olive groves grew abundantly along with the century-old lush forest of Policoro; there were no cities but only a few settlements. The classic Mediterranean landscape of the area also saw the presence of the intensive cultivation of 'cotton wool' as well as the cultivation of liquorice plants along the fertile half moon until 1870. The rivers reshaped the landscape, especially on the plains, and formed marshes, whereas men modified the area with the usurpation of the state-owned allotments and by logging near the cities. The human presence in the area, in contrast to the region as a whole, shows a steady increase in numbers from the eighteenth century with the formation of the two new centres in the twentieth century. The process of modernisation by the middle of the nineteenth century saw a transformation phase in the agrarian landscape through the allotments and the end of feudalism, while in the landscape in the whole area, new elements and components appeared such as roads, railways, telegraph poles and cables.

Baccharis halimifolia L. (Asteraceae) is a shrub native to North America which is invading estuarine communities in Europe. We report the invasion history and the distribution limits of B. halimifolia in Europe, with particular emphasis... more

Baccharis halimifolia L. (Asteraceae) is a
shrub native to North America which is invading
estuarine communities in Europe. We report the invasion
history and the distribution limits of B. halimifolia
in Europe, with particular emphasis on the frequency of
its presence in estuarine communities in Spain. B. halimifolia
has been cultivated in Europe since the 17th
century to present. It was first recorded as naturalized in
the Bay of Biscay in 1906, where it forms currently
stable and locally abundant populations in almost all the
estuaries of Northern Spain and Western France. The
ongoing invasion to the west could reach well conserved
estuarine communities inGalicia (Spain). B. halimifolia
also forms scattered populations in Northern and
Southern France, Belgium, Netherlands, United Kingdom
and Italy. In these countries it has experienced a
rapid expansion during the last years. InNorthern Spain,
subhalophilous communities dominated by rush (Juncus
maritimus) and/or sea couch (Elytrigia atherica),
common reed stands (Phragmites australis) and ungrazed
wet meadows are the most vulnerable to
invasion. The subhalophilous communities are part of
natural habitats of community interest according to the
habitats directive 92/43/EEC. In some areas of Northern
Spain these communities have been totally replaced by
monospecific stands of B. halimifolia. In contrast,
halophilous communities of the low marsh are resistant
to invasion, suggesting that the survival ofB. halimifolia
may be limited by threshold values of salinity and
waterlogging. With this study we want to raise awareness
about the risk of replacement of estuarine subhalophilous
communities by the ongoing invasion of B.
halimifolia in Europe.

Selected summaries of clinical cases from the Royal Infirmary of Edinburgh obtained from 10 contemporary medical student notebooks

Collapse of the marsh ecosystems of southern Iraq after 1991 forced hundreds of thousands of people into urban slums, and led to contamination of the remaining water supply. We will establish three test beds to see whether brackish water... more

Collapse of the marsh ecosystems of southern Iraq after 1991 forced hundreds of thousands of people into urban slums, and led to contamination of the remaining water supply. We will establish three test beds to see whether brackish water returned from oil drilling and refining can be used to construct new salt marshes. These will filter water, provide forage for livestock, create habitat for fish nurseries, and provide new economic opportunities.

Collapse of the marsh ecosystems of southern Iraq after 1991 forced hundreds of thousands of people into urban slums, and led to contamination of the remaining water supply. We will establish three test beds to see whether brackish water... more

Collapse of the marsh ecosystems of southern Iraq after 1991 forced hundreds of thousands of people into urban slums, and led to contamination of the remaining water supply. We will establish three test beds to see whether brackish water returned from oil drilling and refining can be used to construct new salt marshes. These will filter water, provide forage for livestock, create habitat for fish nurseries, and provide new economic opportunities.

Abstract Coastal marshes are known as organic matter producers. The goal of this work is to study tiller demography, standing biomass, and net aerial primary productivity (NAPP) in a Spartina densiflora coastal wetland, using a method... more

Abstract Coastal marshes are known as organic matter producers. The goal of this work is to study tiller demography, standing biomass, and net aerial primary productivity (NAPP) in a Spartina densiflora coastal wetland, using a method applied to permanent sample plots ...