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  • Erosion rather than plant dieback as the mechanism of marsh loss in an estuarine marsh
  • Biomass ; Coastal marsh ; Ecosystem ; Erosion ; Humid environment ; Louisiana ; United States ; Vegetation
  • Coastal marsh loss in Louisiana is attributed to plane dieback caused by processes that stress vegetation, and a common landscape pattern is broken marsh that expands at the expense of suurrounding unbroken marsh. This paper describes an intensive
  • study to test the hypothesis that broken marsh vegetation is more stressed than unbroken marsh vegetation at Marsh Island, and to identify factors limiting vegetation.
  • The response of coastal marshes to sea-level rise: survival or submergence?
  • Coastal environment ; Coastal marsh ; Geochemistry ; Organic materials ; Salinity ; Sea level ; Sedimentology ; Vegetation
  • processes alone is inadequate to predict the response of coastal marshes to sea-level rise.
  • The aim of this paper is to review the responses of various components of the marsh ecosystem to sea-level rise, emphasizing interactions between physical and biotic processes, and to demonstrate that consideration of either geomorphic or vegetative
  • Salinity of marshes along the James Bay coast, Ontario, Canada
  • The salinities of tide water and sediments from the northern and the southern sectors of the coastal marshes are compared. In the north, Bay water of relatively high salinity is introduced to the marsh by tides, as is generally found in coastal
  • marshes elsewhere. The tidewater in southern James Bay has low salinity and the salt in the marsh is released by molecular diffusion from relict salt deposited with the post-glacial Tyrrell sea sediments. This study demonstrates that the salt in coastal
  • marshes may be introduced by different processes and from different sources.
  • The impact of sea-level rise on coastal salt marshes
  • The response of coastal marshes to relative sea-level rise depends upon their ability to maintain their relative elevation through sedimentation. The marshes themselves represent a balance between contemporary depositional and erosional forces
  • . Despite increased international efforts to clarify the response of sea level to future climatic change, predictions of the effect on coastal marshes still requires further understanding of local subsidence, sediment supply and vegetation factors.
  • Hydrodynamics of salt marsh creek systems : implications for marsh morphological development and material exchange
  • Coastal environment ; Earth surface processes ; Geomorphogenesis ; Hydrodynamics ; Norfolk ; Salt marsh ; Sediment transport ; Sedimentary ; Tide ; United Kingdom
  • In this study, the processes of marsh morphological development are analysed. In north Norfolk, highly unsteady creek flows exhibit well-developed velocity and stress transients which result from the nature of tidal priom and the interaction
  • Damming James Bay : II. Impacts on coastal marshes
  • Canada ; Coastal environment ; Dam;Barrage ; Hydraulic works ; Hydrology ; Impact ; Ontario ; Salinity ; Tidal marsh
  • Sulphate reduction as a geomorphological agent in tidal marshes (Great Marshes at Barnstable, Cape Cod, USA)
  • Brackish environment ; Coastal environment ; Environmental degradation ; Hydrochemistry ; Intertidal zone ; Massachusetts ; Model ; Salinity ; Tidal marsh ; United States of America ; Vegetation ; Water temperature
  • Many tidal marsh surfaces feature water-filled depressions, known as salt pans (shallow) or ponds (deeper). In the Great Marshes at Barnstable, Cape Cod, pond formation is an active process. The AA. hypothesize that degradation of organic matter
  • by sulphate-reducing bacteria in these peat-rich marsh deposits is the primary cause of pan and pond formation. Computer simulation suggests that ponds with similar characteristics to those in the Barnstable marshes may develop by sulphate reduction.
  • Numerical simulation of vertical marsh growth and adjustment to accelerated sea-level rise, North Norfolk, UK
  • Coastal environment ; Coastal marsh ; England ; Eustatism ; Fauna ; Flood ; Flora ; Global change ; Model ; Numerical model ; Sea level ; Sedimentation ; United Kingdom
  • This paper outlines the implementation and application of a refined one-dimensional model designed to simulate the vertical adjustment of marsh surfaces to various combinations of sediment supply, tidal levels and regional subsidence
  • , with particular reference to the marshes of north Norfolk, on the East coast of England.
  • Processes governing marsh formation in a rapidly subsiding coastal environment
  • An accretionary budget is developed for Barataria Basin fresh, brackish-intermediate and salt marshes located along a salinity gradient extending inland from the coast. The mineral sediment and organic carbon requirement of individual marsh units
  • in response to water level increase is presented. The life span of salt marshes of the Mississippi River deltaic plain are estimated to be approximately 100 years.
  • The nitrogen budget of a salt marsh ecosystem
  • Salt marshes reduces oxidised nitrogenous compounds to ammonium and particulate nitrogen and export these reduced forms to coastal waters. The internal demands exceed the net imputs of nitrogen by rain, groundwater flow and fixation, suggesting very
  • active uptake conversion, release and recycling of nitrogen within a marsh ecosystem. Nitrogen losses are mainly through tidal exchanges and denitrification, and these two outputs balance the gains. The chemical exchanges among uplands, marshes
  • and coastal water are important in structuring these ecosystems.
  • Rapid climatic change in coastal Southern California inferred from pollen analysis of San Joaquin marsh
  • Pollen analysis and five radiocarbon dates of a 687-cm core provide a detailed chronology of environmental change in a marsh at the head of Newport Bay, Orange County, California. Results and discussion.
  • Freshwater diversions as an ecosystem management tool for maintaining soil organic matter accretion in coastal marshes
  • Coastal environment ; Coastal plain ; Delta ; Ecosystem ; Erosion control ; Hydraulic works ; Louisiana ; Mississippi ; Organic materials ; Sea level ; Subsidence ; Tidal marsh ; United States of America
  • to impact by salt water intrusion and hurricane storm surge forces. The Davis Pond diversion is a conduit between the Mississippi River and the coastal marshes of Barataria basin currently reintroducing river water into the basin leading to lower basin
  • Marsh soil accretion processes were examined at 12 locations in fresh and brackish marshes in Louisiana's northern Barataria Basin estuary. Sedimentation rates were determined by 137 Cs. Soil structure and accretion were controlled primarily
  • by organic matter accumulation rather than mineral sediment deposition with water and entrapped gases occupying the majority of the soil volume. Such organic-based fresh and brackish marsh soil are more fragile than mineral based marsh soils and are subject
  • salinities. This hydrologic management measure should benefit and extend the stability of the studied marsh sites encouraging continued vegetation growth and soil organic matter accumulation.
  • [b1] Dep. of Oceanography and Coastal Sciences, School of the Coast and Environment, Louisiana State Univ., Baton Rouge, Etats-Unis
  • on the development of coastal vegetated wetlands in China
  • China ; Clay mineral ; Coastal environment ; Ecosystem ; Grain size distribution ; Human impact ; Humid environment ; Mangrove ; Salt marsh ; Sedimentary structure ; Sedimentation
  • This paper discusses in detail the distributions, plant characteristics and environmental conditions of the coastal vegetated wetlands in China. Given a great amount of fine sediment by rivers, China's coastal wetlands are accumulated rapidly
  • . This factor combined with the human's ruthless reclaimation makes the marshes inmature. The vegetated wetlands are classified into 4 types, each having differential features in geomorphological background, deposits and vegetation.
  • [b1] Inst. Estuarine and Coastal Research, East China Normal Univ., Shanghai, Chine
  • A system analysis of salt marsh development along the mainland coast of the Dutch Wadden Sea
  • Coastal environment ; Geosystem ; Intertidal zone ; Netherlands (The) ; Salt marsh ; Wadden
  • The main objective of this thesis is to enhance the understanding of salt marsh development along the mainland coast of the Dutch Wadden Sea at different spatial and temporal scales by the use of field data. The study area is located in the eastern
  • Environmental controls on multiscale spatial patterns of salt marsh vegetation
  • Coastal environment ; Denmark ; Jylland ; Salinity ; Salt marsh ; Spatial distribution ; Tidal creek ; Topography ; Vegetation
  • The AA. investigate the topography-vegetation relationship in a Danish salt marsh, focusing upon 2 scales : a macro-scale (ca. 500 m) across the marsh platform, encompasing seaward and landward areas, and a meso-scale (ca. 25 m) across tidal creeks
  • . While long-term sea-level variation and grazing influenced the macro-scale pattern, short-term fluvial-geomorphic processes drove the meso-scale pattern. The results suggest that, in salt marshes, elevation plays a still more important ecological role
  • Spatial heterogeneity and domain of scale on the Skallingen salt marsh, Denmark
  • Biodiversity ; Biogeography ; Coastal environment ; Denmark ; Ecosystem ; Jylland ; Plant species ; Salt marsh ; Scale ; Spatial variation
  • The study area is the Skallingen salt marsh in Jutland. The AA. specifically aim to identify the domain of scale over which vegetation pattern and process are detected on a salt marsh. Such identification will be achieved by 1) examining the species
  • of emerging novel theory that emphasizes scale-dependent complexity in salt marsh ecosystems.
  • Soils of a dune coastal salt marsh system in relation to groundwater level, micro-topography and vegetation under a semiarid Mediterranean climate in SE Spain
  • Coastal environment ; Dune ; Ecosystem ; Humid environment ; Mediterranean area ; Murcia ; Salt marsh ; Sea level ; Soil ; Soil properties ; Spain ; Vegetation
  • Twenty-one soil profiles were described, analysed and classified in a salt marsh dune system in SE Spain. The aims of this work were to establish the edaphic characteristics of a coastal dune system in SE Spain in relation to its groundwater level
  • Sedimentation rates in the Wanggang salt marshes, Jiangsu
  • China ; Coastal environment ; Grain size distribution ; Humid environment ; Isotope dating ; Jiangsu ; Salt marsh ; Sediment budget ; Vegetation
  • and Spartina alterniflora, were introduced successively into the Jiangsu coastal areas, in order to protect the coastline from erosion and to increase the accumulation rate. Pb-210 and Cs-137 analyses were carried out for sediment samples from the salt-marshes
  • The total area of coastal wetlands exceeds 5000 km2 in Jiangsu Province, but it is decreasing rapidly in response to the intense reclamation activities and coastal erosion along a part of the coastline. Hence, 2 types of plants, Spartina angelica
  • Chemical environment of coastal marshes and swamps, Louisiana
  • Chronosequential alterations in soil organic matter during initial development of coastal salt marsh soils at the southern North Sea
  • Chronosequence ; Coastal environment ; Coastal marsh ; Germany ; Niedersachsen ; North Sea ; Organic materials ; Pedogenesis ; Soil properties ; Spatial analysis
  • This study was conducted in the coastal zone located in Cäciliengroden, Jadebusen Bay (North Germany). The aim was to examine the changes in organic matter properties along a salt marsh soil chronosequence. Three soil profiles were located in low
  • , middlehigh and high marsh zones, between the mud flat tidal area and the dike. The AA. propose a pattern of spatial changes in properties of salt marsh soils along the studied chronosequence. The results lead to the conclusion that some organic matter