Alternate state theory and tidal freshwater mudflat experimental ecology on Anacostia River, Washington, D.C.
The concept that multiple community states may alternately exist for some ecosystems has been the subject of controversy for decades. This theory is tested and applied to the mudflats of the low/middle marsh intertidal zone of two restored freshwater tidal marshes on the Anacostia River. It is belie...
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ftunivmaryland:oai:drum.lib.umd.edu:1903/7589 2023-05-15T15:46:21+02:00 Alternate state theory and tidal freshwater mudflat experimental ecology on Anacostia River, Washington, D.C. may, peter Kangas, Patrick Digital Repository at the University of Maryland University of Maryland (College Park, Md.) Marine-Estuarine-Environmental Sciences 2007-11-13 38804830 bytes application/pdf http://hdl.handle.net/1903/7589 en_US eng http://hdl.handle.net/1903/7589 Environmental Sciences tidal freshwater intertidal mudflat emergy exclosure alternate state theory Dissertation 2007 ftunivmaryland 2022-11-11T11:13:19Z The concept that multiple community states may alternately exist for some ecosystems has been the subject of controversy for decades. This theory is tested and applied to the mudflats of the low/middle marsh intertidal zone of two restored freshwater tidal marshes on the Anacostia River. It is believed that experimental exclosures exposed strong species interactions and provided a window with which to view the potential alternate existence of two structurally different systems, intertidal mudflat and emergent marsh. The occurrence, persistence and community composition of the two ecosystem states are examined through experimental exclosures at the two marsh restoration study areas. The power of large grazers to deflect the goals of wetland restoration practitioners is studied in the context of alternate state theory. Initially unvegetated mudflat, native marsh vegetation emerged within exclosure study areas at two restoration sites. Resident Canada geese (Branta canadensis maxima) decimated planted areas of restored marsh left open to grazing, returning marsh to unvegetated mudflats. Data from exclosures are presented on macrophyte community composition, sediment elevation, bird, fish, invertebrate and algae associations from two separate sets of Anacostia River experimental exclosure sites, one covering 588 m2, the other covering 2,700 m2. Results support the hypothesized alternate existence of the two system states in the same space and relative time, each dependant upon the access of a critical mass of large grazers. A description of the mudflat biotic community and its interconnectivity is discussed as an important feature of the Anacostia River system. An emergy analysis of each state and an accounting of fisheries energy flow is conducted. Information collected relating to the pre-restoration (tidal mudflat) and post-restoration (emergent marsh) physical and biological conditions are detailed and analyzed. A determination of the emergy inputs for a large-scale marsh restoration project are calculated and ... Doctoral or Postdoctoral Thesis Branta canadensis University of Maryland: Digital Repository (DRUM) Canada |
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Open Polar |
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University of Maryland: Digital Repository (DRUM) |
op_collection_id |
ftunivmaryland |
language |
English |
topic |
Environmental Sciences tidal freshwater intertidal mudflat emergy exclosure alternate state theory |
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Environmental Sciences tidal freshwater intertidal mudflat emergy exclosure alternate state theory may, peter Alternate state theory and tidal freshwater mudflat experimental ecology on Anacostia River, Washington, D.C. |
topic_facet |
Environmental Sciences tidal freshwater intertidal mudflat emergy exclosure alternate state theory |
description |
The concept that multiple community states may alternately exist for some ecosystems has been the subject of controversy for decades. This theory is tested and applied to the mudflats of the low/middle marsh intertidal zone of two restored freshwater tidal marshes on the Anacostia River. It is believed that experimental exclosures exposed strong species interactions and provided a window with which to view the potential alternate existence of two structurally different systems, intertidal mudflat and emergent marsh. The occurrence, persistence and community composition of the two ecosystem states are examined through experimental exclosures at the two marsh restoration study areas. The power of large grazers to deflect the goals of wetland restoration practitioners is studied in the context of alternate state theory. Initially unvegetated mudflat, native marsh vegetation emerged within exclosure study areas at two restoration sites. Resident Canada geese (Branta canadensis maxima) decimated planted areas of restored marsh left open to grazing, returning marsh to unvegetated mudflats. Data from exclosures are presented on macrophyte community composition, sediment elevation, bird, fish, invertebrate and algae associations from two separate sets of Anacostia River experimental exclosure sites, one covering 588 m2, the other covering 2,700 m2. Results support the hypothesized alternate existence of the two system states in the same space and relative time, each dependant upon the access of a critical mass of large grazers. A description of the mudflat biotic community and its interconnectivity is discussed as an important feature of the Anacostia River system. An emergy analysis of each state and an accounting of fisheries energy flow is conducted. Information collected relating to the pre-restoration (tidal mudflat) and post-restoration (emergent marsh) physical and biological conditions are detailed and analyzed. A determination of the emergy inputs for a large-scale marsh restoration project are calculated and ... |
author2 |
Kangas, Patrick Digital Repository at the University of Maryland University of Maryland (College Park, Md.) Marine-Estuarine-Environmental Sciences |
format |
Doctoral or Postdoctoral Thesis |
author |
may, peter |
author_facet |
may, peter |
author_sort |
may, peter |
title |
Alternate state theory and tidal freshwater mudflat experimental ecology on Anacostia River, Washington, D.C. |
title_short |
Alternate state theory and tidal freshwater mudflat experimental ecology on Anacostia River, Washington, D.C. |
title_full |
Alternate state theory and tidal freshwater mudflat experimental ecology on Anacostia River, Washington, D.C. |
title_fullStr |
Alternate state theory and tidal freshwater mudflat experimental ecology on Anacostia River, Washington, D.C. |
title_full_unstemmed |
Alternate state theory and tidal freshwater mudflat experimental ecology on Anacostia River, Washington, D.C. |
title_sort |
alternate state theory and tidal freshwater mudflat experimental ecology on anacostia river, washington, d.c. |
publishDate |
2007 |
url |
http://hdl.handle.net/1903/7589 |
geographic |
Canada |
geographic_facet |
Canada |
genre |
Branta canadensis |
genre_facet |
Branta canadensis |
op_relation |
http://hdl.handle.net/1903/7589 |
_version_ |
1766381054045716480 |