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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

An evaluation of vegetation and wildlife communities in mitigation and natural wetlands of West Virginia

Balcombe, Collins K. January 2003 (has links)
Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains xx, 417 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references.
12

Effects of water-level management on the abundance and habitat use of waterfowl and marsh birds in the Saskatchewan River Delta, Manitoba, Canada

Baschuk, Mark 12 October 2010 (has links)
Waterbird habitat in the Saskatchewan River Delta (SRD) has been altered by numerous upstream and downstream anthropogenic developments. Wetland water-level management has been used in an attempt to mitigate these changes, but the effects on the local waterbird community are unknown. Using an experimental approach, I examined the effects of wetland water-level management on waterfowl and marsh birds in the SRD. In 2007, three wetland basins in the Summerberry Marsh Complex, Manitoba were partially drawn down and paired with three additional wetlands managed with high water levels. In 2008-09, I surveyed waterfowl within the study wetlands during different life stages using point counts and aerial surveys. Abundances of breeding marsh birds, including American Bitterns, Least Bitterns, Soras, Virginia Rails, Yellow Rails, American Coots, and Pied-billed Grebes were estimated using call-response surveys. Generalized linear and generalized linear mixed models were used to determine relationships between relative bird abundances and the physical characteristics, vegetation characteristics, and forage fish and invertebrate abundances within the wetlands. Dabbler species of waterfowl preferred the partial drawdown wetlands during nearly all life stages, except brooding. Diver species preferred the non-drawdown wetlands, but only during the spring-breeding and fall-staging periods. Invertebrate abundance affected wetland use by dabbler and diver species, particularly during the spring-breeding and brooding periods. Subsequently, wetlands with high forage fish abundances were avoided. In the fall, dabbler densities on the partial drawdown wetlands increased from an average of 0.4 birds per hectare to 1.5 birds per hectare. This influx was likely due to the accessibility and availability of submerged aquatic vegetation. The partial water-level drawdowns did not benefit any species of marsh birds examined. American Bitterns, American Coots, and Pied-billed Grebes chose the deeper, non-drawdown wetlands, due to high abundances of forage fish. Vegetation interspersion, particularly that offered by Schoenoplectus, was preferred by these species. Soras and Virginia Rails were not affected by water depth or vegetation characteristics, but were positively correlated to invertebrate abundances. Subsequently, the Sora avoided wetlands with high forage fish abundance. The conditions created by the partial water-level drawdowns did not meet the requirements of all species present in the SRD. Therefore, future wetland management should focus on providing a wide range of water depths within wetland complexes to accommodate the requirements of different avian species.
13

Effects of water-level management on the abundance and habitat use of waterfowl and marsh birds in the Saskatchewan River Delta, Manitoba, Canada

Baschuk, Mark 12 October 2010 (has links)
Waterbird habitat in the Saskatchewan River Delta (SRD) has been altered by numerous upstream and downstream anthropogenic developments. Wetland water-level management has been used in an attempt to mitigate these changes, but the effects on the local waterbird community are unknown. Using an experimental approach, I examined the effects of wetland water-level management on waterfowl and marsh birds in the SRD. In 2007, three wetland basins in the Summerberry Marsh Complex, Manitoba were partially drawn down and paired with three additional wetlands managed with high water levels. In 2008-09, I surveyed waterfowl within the study wetlands during different life stages using point counts and aerial surveys. Abundances of breeding marsh birds, including American Bitterns, Least Bitterns, Soras, Virginia Rails, Yellow Rails, American Coots, and Pied-billed Grebes were estimated using call-response surveys. Generalized linear and generalized linear mixed models were used to determine relationships between relative bird abundances and the physical characteristics, vegetation characteristics, and forage fish and invertebrate abundances within the wetlands. Dabbler species of waterfowl preferred the partial drawdown wetlands during nearly all life stages, except brooding. Diver species preferred the non-drawdown wetlands, but only during the spring-breeding and fall-staging periods. Invertebrate abundance affected wetland use by dabbler and diver species, particularly during the spring-breeding and brooding periods. Subsequently, wetlands with high forage fish abundances were avoided. In the fall, dabbler densities on the partial drawdown wetlands increased from an average of 0.4 birds per hectare to 1.5 birds per hectare. This influx was likely due to the accessibility and availability of submerged aquatic vegetation. The partial water-level drawdowns did not benefit any species of marsh birds examined. American Bitterns, American Coots, and Pied-billed Grebes chose the deeper, non-drawdown wetlands, due to high abundances of forage fish. Vegetation interspersion, particularly that offered by Schoenoplectus, was preferred by these species. Soras and Virginia Rails were not affected by water depth or vegetation characteristics, but were positively correlated to invertebrate abundances. Subsequently, the Sora avoided wetlands with high forage fish abundance. The conditions created by the partial water-level drawdowns did not meet the requirements of all species present in the SRD. Therefore, future wetland management should focus on providing a wide range of water depths within wetland complexes to accommodate the requirements of different avian species.
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

A geospatial methodology for assessing wetland vulnerability under anthropogenic pressures at a watershed scale

Ma, Jia, Ji, Wei. January 2006 (has links)
Thesis (Ph. D.)--Dept. of Geosciences and School of Computing and Engineering. University of Missouri--Kansas City, 2006. / "A dissertation in geoscience and software architecture." Advisor: Wei Ji. Typescript. Vita. Title from "catalog record" of the print edition Description based on contents viewed Nov. 13, 2007. Includes bibliographical references (leaves 248-261). Online version of the print edition.
16

Drying and re-wetting of organic wetland sediments biogeochemistry and implications for wetland management /

Sommer, Beate. January 2006 (has links)
Thesis (Ph.D.)--Edith Cowan University, 2006. / Submitted to the Faculty of Computing, Health and Science. Includes bibliographical references.
17

High rates of ammonia removal in constructed treatment wetland mesocosms using oxygenation

Palmer, Huckleberry Richardson, January 2008 (has links) (PDF)
Thesis (M.S.)--Washington State University, May 2008. / Includes bibliographical references (p. 18-19).
18

Small scale farming on Wetland resource utilisation: a case study of Mandlanzini, Richards Bay

Mthiyane, Thokozani Sivikele January 2009 (has links)
A Dissertation Submitted to the Faculty of Education in Partial Fulfilment of the Requirements for the Masters of Environmental Education in the Department of Mathematics, Science and Technology Education at the University of Zululand, 2009. / Wetland utilisation by rural communities in South Africa poses a serious challenge for natural resource conservation. The growing rate of rural poverty, poor education and socio-cultural beliefs contribute towards the current plight of many wetlands. The challenge that faces wetland sustainability stems from the over utilisation of wetland resources for survival as well as cultural activities that are practiced. This study aimed at investigating the impact of various wetland activities performed on a daily basis by local communities of Mandlanzini in the quest for survival. The community groups were selected to study their way of life and their relation to their local environment in order to deepen the understanding of their activities and impact on the wetland. Household data collected, gave a clear picture of socio-economic status of the community. The results of the study showed that community members, on the lower end of salary scales, were the ones who relied heavily on raising income by using resources available from the wetland. Research data showed that, there is a high demand for staple food such as ‘amandumbe’, banana, and sweet potatoes by the community under study. The study also showed that indigenous knowledge can play an important role towards the restoration of wetlands. Furthermore, as many community members practiced subsistence agriculture, most of their livestock depend on wetland resources. All these constituted good reasons why communities should be involved in wetland management and conservation.
19

Wetland pollutant removal effectiveness and mitigation related to Ohio highways

Hall, Daniel Glenn January 1996 (has links)
No description available.
20

Effects of timing and duration of flooding on phosphorus release in four restored wetlands around Agency and Upper Klamath Lakes, Oregon /

Stevens, Carla J. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 40-48). Also available on the World Wide Web.

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