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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

Stream channel stability and channel evolution in a rapidly urbanizing, ridge-and valley watershed, Beaver Creek, Knox County, Tennessee

Keaney, Francis Bartholomew. January 2009 (has links)
Thesis (M.S.)--University of Tennessee, Knoxville, 2009. / Title from title page screen (viewed on Mar. 12, 2010). Thesis advisor: Qiang He. Vita. Includes bibliographical references.
12

Sustainability and biodiversity : the impact, alternative design and prospects of restoration of channelized lowland streams in Hong Kong /

Chan, Pui-lok, Bosco. January 2001 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 325-365).
13

The role of adjacent vegetation on the recovery of riparian flora : Effect of upstream and upland vascular vegetation after stream restoration in a boreal catchment

Kretz, Lena January 2015 (has links)
Restoration of streams that were formerly channelized for timber-floating has become increasingly common. Generally, this restoration returns boulders from riparian zones to streams, leading to wider, more heterogeneous channels with slower flows. The primary goal is to enhance fish populations, but riparian vegetation is also expected to be favoured. However, increases in floristic diversity have not been observed and reasons for this slow response are still unknown. One possible explanation might be the lack of colonist pools. I therefore investigated how surrounding plant compositions influence riparian recovery. The vascular plant flora was identified in riparian sites and in adjacent upstream riparian and upland sites. Four reach types were included: unchannelized, channelized, restored and demonstration restored. Species richness and floristic similarities among types of sites and reaches were compared. Correlations with upland and upstream channel slopes were made and the importance of variation in seed floating ability was tested. The results show that unchannelized reaches were floristically similar to their adjacent upstream riparian and upland sites, whereas channelized reaches showed more different floras. Restoration created a somewhat more homogeneous flora among the three site types and demonstration restored reaches were most similar to upstream sites. Soil moisture conditions (i.e. wetland vs. forest) in the uplands had stronger impacts on species similarities than upland or upstream channel slopes. I conclude that adjacent sites are important for floristic recovery of riparian reaches and that demonstration restoration is most advantageous for riparian recovery. I recommend protection of upland sites from forestry to facilitate recovery. / Local- and landscape-scale effects on biodiversity after stream restoration
14

Monitoring of responses to a local base-level change in an ephemeral stream

Kaehler, Charles Alfred January 1980 (has links)
No description available.
15

Use of phytometers for evaluating ecological restoration

Dietrich, Anna L. January 2013 (has links)
The increase in ecological restoration can be attributed to valuation of healthyecosystems and concerns for future climate changes. Freshwaters belong among theglobally most altered ecosystems and are restored to counteract human impacts.Many Swedish streams that were channelized to facilitate timber floating have beenrestored by returning boulders and reconnecting riparian with instream habitats.Evaluation of restoration lacks reliable indicators of organism performance, possiblydue to the complexity of ecosystem responses. Phytometers, i.e. standardized plantstransplanted to different environments, are important indicators of restorationsuccess. Phytometers integrate multiple environmental factors and measureecosystem functions directly. This thesis combines a literature review with threeexperiments and focuses on phytometer use for evaluating ecological restoration. Werecommend using different phytometer species, life-forms and life-stages and longexperiments (>1 year) to obtain high resolution and generality (I). In greenhouse andfield experiments we investigated the effect of restoring channelized rivers onphytometers and abiotic variables in the riparian zone. We hypothesized thatphytometer performance varies with stream size and climate. In the greenhouse, weanalysed differences in fertility between channelized and restored reaches by growingphytometers on soils from experimental sites (II). Phytometers grew better on soilsfrom restored sites in small streams, indicating a positive effect of restoration on soil.We detected this effect already 3-7 years after restoration, suggesting a fasterrecovery than predicted. In a short-term field experiment focusing on germinationand establishment of sunflowers, seedling survival, substrate availability, and soilnutrient content in large streams were enhanced by restoration (III). Overall,phytometers performed best at high altitudes and short growing seasons. The use ofMolinia caerulea and Filipendula ulmaria as phytometers in a long-term fieldexperiment (IV) revealed a better performance at restored sites. One reason was thatsummer flow-variability was higher, particularly in medium-sized streams. Sincephytometers allocated more biomass to belowground parts at restored compared tochannelized sites, it seems important to separate above- and belowground biomass inrestoration evaluation. Restoration outcomes vary with location in the catchment.Knowing such potentially different responses could guide restorationists in where tolocate restoration to be effective or successful. We suggest that small streams reactparticularly fast to restoration. Given that the proportion of small streams is high andthat restoration success in headwaters may favour downstream reaches, werecommend restoration to begin in tributaries to larger rivers. It is not always knownwhy phytometers react the way they do. Greenhouse experiments can disentangle thecauses of phytometer responses in the field by focusing on single environmentalfactors. We demonstrate that phytometers integrate ecosystem responses torestoration by reflecting how environmental factors affect plants under fieldconditions. Further studies are needed to better understand the underlyingmechanisms.
16

Pre-fire functional condition and post-fire channel changes in northern Nevada streams 1999-2001 fires /

Kozlowski, Donald F. January 2007 (has links)
Thesis (M.S.)--University of Nevada, Reno, 2007. / "December, 2007." Includes bibliographical references (leaves 115-122). Online version available on the World Wide Web.
17

Riparian cover changes associated with flow regulation and bank stabilization along the Upper Willamette River in Oregon between 1939 and 1996 /

Gutowsky, Sharon L. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2000. / Typescript (photocopy). Includes bibliographical references (leaves 80-82). Also available on the World Wide Web.
18

Sustainability and biodiversity the impact, alternative design and prospects of restoration of channelized lowland streams in Hong Kong /

Chan, Pui-lok, Bosco. January 2001 (has links)
Thesis (Ph.D.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 325-365) Also available in print.
19

Investigating the riffle-pool/meander link : a comparative analysis of horizontal and vertical undulations in stream channel morphology /

Lofthouse, Caroline J. January 2007 (has links)
Thesis (M.Sc.)--York University, 2007. Graduate Programme in Geography. / Typescript. Includes bibliographical references (leaves 80-82). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR29578
20

Stream channel adjustments following logging road removal in Redwood National Park

Klein, Randy D. January 1987 (has links)
Thesis (M.S.)--Humboldt State University, 1987. / Typescript (photocopy). Includes bibliographical references (leaves 54-56).

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