Processes Influencing Marsh Elevation Change in Low- and High-Elevation Zones of a Temperate Salt Marsh

Abstract The overall trend of rapid retreat of Alpine glaciers contains considerable variability of responses at the scale of individual glaciers. As a step towards a regional assessment of glacier state that allows a detailed differentiation of single glaciers, we explore the potential of a self-organizing maps (SOM) algorithm to identify and cluster recurring patterns of thickness change at glaciers in western Austria. Using digital elevation models and glacier inventories for three time periods, we compute the frequency distribution of surface elevation change over the area of each glacier in the data set, for each period. The results of the SOM clustering show a distinct pattern shift over time: From 1969 to 1997, surface elevation change occurred at relatively uniform rates across a given glacier. Since 1997, the distribution of surface elevation change at individual glaciers has been far less uniform, indicating accelerated processes of disintegration. Tracking the evolution of individual glaciers throughout the time periods via the clusters highlights both the broader regional trend as well as glaciers that deviate from this trend, e.g. some very small, high elevation glaciers that have reverted to reduced and more uniform volume loss patterns.

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Restoring marsh elevation in a rapidly subsiding salt marsh by thin-layer deposition of dredged material

Ecological Engineering ◽

10.1016/s0925-8574(98)00061-5 ◽

1999 ◽

Vol 12 (3-4) ◽

pp. 189-205 ◽

Cited By ~ 79

Author(s):

Mark A Ford ◽

Donald R Cahoon ◽

James C Lynch

Keyword(s):

Salt Marsh ◽

Thin Layer ◽

Dredged Material ◽

Marsh Elevation ◽

Layer Deposition

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Annual nitrogen budget of a temperate coastal barrier salt-marsh system along a productivity gradient at low and high marsh elevation

Perspectives in Plant Ecology Evolution and Systematics ◽

10.1078/1433-8319-00008 ◽

2000 ◽

Vol 3 (2) ◽

pp. 128-141 ◽

Cited By ~ 18

Author(s):

Harm J. van Wijnen ◽

Jan P. Bakker

Keyword(s):

Salt Marsh ◽

Nitrogen Budget ◽

High Marsh ◽

Coastal Barrier ◽

Marsh Elevation ◽

Productivity Gradient

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Responses of Salt Marsh Plant Rhizosphere Diazotroph Assemblages to Changes in Marsh Elevation, Edaphic Conditions and Plant Host Species

Microbial Ecology ◽

10.1007/s00248-010-9757-8 ◽

2010 ◽

Vol 61 (2) ◽

pp. 386-398 ◽

Cited By ~ 17

Author(s):

Debra A. Davis ◽

Megan D. Gamble ◽

Christopher E. Bagwell ◽

Peter W. Bergholz ◽

Charles R. Lovell

Keyword(s):

Salt Marsh ◽

Host Species ◽

Marsh Plant ◽

Plant Host ◽

Salt Marsh Plant ◽

Edaphic Conditions ◽

Marsh Elevation

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Temporal and Spatial Accretion Patterns and the Impact of Livestock Grazing in a Restored Coastal Salt Marsh

Estuaries and Coasts ◽

10.1007/s12237-021-00963-w ◽

2021 ◽

Author(s):

E. C. Koppenaal ◽

P. Esselink ◽

W. E. van Duin ◽

J. P. Bakker

Keyword(s):

Salt Marsh ◽

Seasonal Pattern ◽

Livestock Grazing ◽

Sediment Supply ◽

Surface Elevation ◽

Elevation Change ◽

Coastal Salt Marsh ◽

Linear Relationships ◽

Surface Elevation Change ◽

The Impact

AbstractA summer polder had developed a deficit in surface elevation of about 20 cm in respect to rising sea level during its almost one-hundred-year period of embankment. We addressed the questions whether the distance of the restored site to the intertidal flats and continuation of livestock grazing in the restored site could hamper surface-elevation change during the first 10 years after de-embankment of the summer polder. The surface-elevation change showed similar positive linear relationships with annual tidal flooding in both the reference salt marsh and the restored site, indicating that the surface-elevation change in the restored site was not moderated by the distance from the sea. The surface-elevation change had a clear seasonal pattern with positive values in winter and negative values during summer. The surface-elevation change was 11 mm/year in the grazed reference salt marsh and 7 mm/year in the grazed restored site, but amounted to 17 mm/year in ungrazed exclosures in the restored site, showing that grazing retarded the catching up of the elevation deficit in the restored site. The surface-elevation change within the restored site was higher close to the constructed creeks indicating the inception of levee formation. The surface-elevation change was also positively affected by the proximity of breaches in the embankment, but this effect was less clear than the effect of creeks. We conclude that the surface-elevation deficit may be compensated in the Wadden Sea summer polders by their de-embankment when sediment supply is high, whereas livestock grazing retards this process. Dug creeks increase spatial variation in the restored site.

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