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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Structure-forming benthic invertebrates : habitat distributions on the continental margin of Oregon and Washington /

Strom, Natalie A. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2006. / Printout. Includes bibliographical references (leaves 45-48). Also available on the World Wide Web.
12

Infaunal communities in South Australian temperate mangrove systems

Indarjani, January 2003 (has links)
South Australian mangroves consist of only one single species Avicennia marina (Fosk.) Vierh.var australasica (Walp) Moldenke, 1960. They are distributed discontinuously within St. Vincent Gulf and Spencer Gulf and provide significant valuable habitat both in economical and ecological terms. The Fisheries Act 1971-1982 protected the existence of mangroves and the Harbour Act 1936-1981 controlled removal of mangrove areas in coastal development. To date very few ecological studies have been conducted in the South Australian mangroves, particularly on the infaunal organisms that have an important role in maintaining the ecological dynamic within the estuaries systems. As this is the first study on infaunal mangrove communities in the inverse estuaries of South Australia, there was no prior data for ecological comparison. The study was conducted at three mangroves location (Garden Island, Middle Beach and Saint Kilda) close to Adelaide in May 2000 and 2001. Overall the study has reported that the infaunal mangrove assemblages of South Australian mangroves were comparable to other temperate mangroves. The infaunal communities were characterised by lower diversity and abundance compared to the tropical or subtropical mangroves. The infaunal zonation related to the tidal gradient and habitat variation was detected. Most infauna organisms occupied the surface layers and substantially decreased towards the deeper layers. The study also suggested that sediment structure of mangrove systems were complex and infaunal communities responded differently to the change of environmental conditions both in small scale and larger scale. Thus, assessing the infaunal communities structure in mangrove systems should be based on ecological characteristics rather than geographical positions. The examination of dominant polychaetes families showed that different species have different responses to the environmental cues within mangrove systems. The study did not find that any polychaete species was restricted to mangroves only as they all were also found in the habitat adjacent mangrove forest. / Thesis (Ph.D.)--School of Earth and Environmental Sciences, 2003.
13

The influence of coarse woody debris, disturbance, and restortion on biological communities in sandy coastal plain streams

Mitchell, Richard Morgan. Feminella, Jack W. January 2009 (has links)
Dissertation (Ph.D.)--Auburn University, / Abstract. Includes bibliographic references.
14

Aquatic invertebrate, vegetation, and hydrology assessment of Long Meadow Lake prior to effects of hydrological manipulations /

Becker, Lindsey M. January 2007 (has links) (PDF)
Thesis (M.S.)--University of Wisconsin--Stevens Point, 2007 / Includes bibliographical references (leaves 37-49).
15

Benthic macroinvertebrate diversity in a shallow estuary : controls on nutrient and algal dynamics /

McLenaghan, Natalie Ann. January 2009 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 2009. / Typescript. Includes bibliographical references (leaves 113-123).
16

The ecological role of a common seastar (Patiriella spp.) within intertidal cobble fields : a thesis submitted to the Victoria University of Wellington in partial fulfilment of the requirements for the degree of Master of Science in Marine Biology /

Palmer, Shiree. January 2010 (has links)
Thesis (M.Sc.)--Victoria University of Wellington, 2010. / Includes bibliographical references.
17

Using aquatic arthropods to compare cattle grazing regimes and buffer strips along southwestern Wisconsin streams

Weigel, Brian M. January 1998 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1998. / Typescript. Includes bibliographical references (leaves 24-29).
18

Relationships between eelgrass (Zostera marina) habitat characteristics and juvenile dungeness crab (Cancer magister) and other invertebrates in southern Humboldt Bay, California, USA /

Williamson, Kathleen Janice. January 1900 (has links)
Thesis (M.A.)--Humboldt State University, 2006. / Includes bibliographical references (leaves 42-46). Also available via Humboldt Digital Scholar.
19

The influence of water velocity on aquatic macroinvertebrate functional structure and production in the Cache River in Southern Illinois.

Scholl, Eric 01 May 2013 (has links)
The Cache River, located in southern Illinois, faces a unique set of restoration challenges due to multiple anthropogenic modifications to the watershed. In 1915 the Cache River was disconnected and divided into two sub-watersheds, the upper Cache River (UCR) and the lower Cache River (LCR). This alteration has led to impairments in both sections of the Cache River. The UCR currently suffers from channel incision and wetland loss due to an increase in channel slope, while the LCR experiences decreased flows and related habitat degradation. Currently, watershed managers are proposing to restore a more natural flow regime to the LCR through some degree of hydrologic reconnection. I quantified the effects of small-scale differences in flow velocities on snag-dwelling aquatic macroinvertebrates in the UCR and LCR. My study was designed to provide critical information on potential ecological responses to proposed reconnection of the Cache River by examining the effects of flow on elements of ecosystem structure (macroinvertebrate community structure, diversity, richness, evenness, biomass, and abundance) and function (secondary production). Total snag-dwelling macroinvertebrate abundance was higher in the LCR (p < 0.001), and both total biomass and total production did not differ between the UCR and LCR. Passive filter-feeders (families Hydropsychidae and Simuliidae), EPT taxa (orders Ephmeroptera Plecoptera and Trichoptera), and Elmidae were more abundant and had higher biomass on snags in the UCR compared to the LCR. Due to high variability in estimates, only Elmidae production was higher in the UCR (p < 0.05), with non-significant trends of higher production of passive filter-feeders and EPT taxa in the UCR. Non metric multidimensional scaling (NMDS) ordinations showed different communities on snags in the UCR and LCR, and analysis of similarity indicated these differences were significant (ANOSIM Global R = 0.98, p < 0.05). This UCR community was more diverse (p < 0.05) and composed of larger-sized individuals than the LCR (p < 0.001). In contrast, the LCR community was composed mainly of taxa that are associated with very low flows (e.g., zooplankton), tolerant of degraded conditions (e.g., Isopoda and Chironomidae), and generally smaller in body size. Although not statistically significant, there was a trend for higher total production in the LCR (28.90 ± 54.51) (mean ± 95% CI) than the UCR (10.22 ± 6.43). This trend was driven primarily by a patchily distributed Chironomidae, which were highly productive on some LCR snags. However, given the degraded water quality in the LCR, the ultimate fate of this production is not clear. The more natural flow regime in the UCR is likely driving many of the differences between the UCR and LCR that I observed, but relationships may be complex, as flow influences biota in numerous direct and indirect ways. This study is the first I know of to examine the structure and function of macroinvertebrate communities prior to hydrologic restoration of a river. Results will assist resource managers in the justification, planning, and execution of hydrologic restoration in the Cache watershed. Given that many river restoration projects are not based on sound ecological information and principles, this project can also serve as a model for future river restoration efforts.
20

Aquatic invertebrate-habitat relationships and stream channel cross section area change in response to streamside management zones in North Central Mississippi /

Luecker, Terry A. January 2004 (has links)
Thesis (M.S.)--Oregon State University, 2005. / Printout. Includes bibliographical references (leaves 51-55). Also available on the World Wide Web.

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