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Keying forest stream protection to aquatic ecosystem values in multi-ownership watershedsPickard, Brian R. 15 March 2013 (has links)
Forested lands of western Oregon provide aquatic habitat for many fish and riparian dependent species, including a wide variety of salmon species. Current policies set riparian protections using fixed buffers on streams for federal and private lands based on stream type or size. These buffers can create a series of disjointed riparian protections, as federal lands require buffers that are much larger than private lands. In addition, the fixed buffer approach is neither flexible nor tailored to aquatic ecosystem values. This thesis presents a framework for comprehensively assessing stream networks using site specific watershed features and then suggests riparian conservation strategies that key stream and riparian protection to aquatic ecosystem values. Seven study watersheds were used in this analysis, totaling over 2.5 million acres of forested lands in western Oregon. Employing a set of geospatial tools, called NetMap, streams in each watershed were classified into higher and lower priorities using criteria of intrinsic potential, erosion/debris flow susceptibility, and thermal loading potential. Results demonstrated the inherent variability within and among watersheds based on the geomorphic and ecological processes determined important for selected salmon species. Within each watershed, both federal and non-federal lands had many miles of higher priority fish-bearing and non-fish bearing streams, suggesting the need for comprehensive, holistic watershed conservation strategies.
Based on the partitioning of streams into higher and lower priorities, an alternative riparian conservation strategy was then modeled for federal lands that allocate protection on the basis of the ecological context of a stream segment’s potential and particular location while still meeting federal aquatic conservation goals and objectives. Possible increases to the land base for long-term timber production were then identified if this strategy were applied to federal Matrix lands. Results demonstrated that 8-30 percent of the current riparian buffers could be reallocated to the land base for long-term timber production. An additional 26-45 percent of current buffers could be managed simultaneously for both timber production and aquatic ecosystem goals. Results also provided a framework for targeting of conservation and restoration efforts towards higher priority streams within each watershed. As many of the most ecologically important streams were located on non-federal lands, riparian conservation policies focused on streams classified as higher priority on those lands may be needed to protect aquatic species and their environments. / Graduation date: 2013
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CE-QUAL-W2 Water Quality and Fish-bioenergetics Model of Chester Morse Lake and the Cedar RiverWells, Vanessa I. 01 January 2011 (has links)
Many communities are currently seeking to balance urban water needs with preservation of sensitive fish habitat. As part of that effort, CE-QUAL-W2, a hydrodynamic and temperature model, was developed for Chester Morse Lake and the lower Cedar River, WA. Chester Morse Lake is approximately 10 km long with a maximum depth at full pool of 40 m. The Cedar River model started immediately downstream of the Chester Morse dam and ended 21 km downstream at Landsburg, where drinking water is diverted for the City of Seattle. This water quality model was coupled with a fish habitat and bioenergetics model for bull trout and was calibrated to temperature data between 2005 and 2008. Bull trout fish bioenergetics parameters were provided by the USGS. The CE-QUAL-W2 model was found to be highly accurate in modeling temperature variation in the lake - at most locations having an average absolute mean error of between 0.5 and 0.8 oC. The Cedar River model had an average absolute mean error of 0.7oC. This tool is designed to allow managers and operators to estimate the impact to fish habitat and growth potential from various management decisions including extent of drawdown, timing/volume of flows, and various pumping operations. Future studies could include incorporating further water quality parameters such as nutrients, algae, and zooplankton as they relate to fish productivity.
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Environmental concern in South Africa : an analysis of elite and public attitudes and their implications for public policyZeelie, Hein 12 1900 (has links)
Thesis (MPhil)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: South Africa, like so many other developing countries, is confronted with a very complex
situation: although large-scale environmental degradation is threatening the future of the
country, environmental matters are not regarded as of sufficient importance amongst the
general population for them to contribute to environmental improvements. Most of the
country's populations, many argue, are simply too poor and too focused on fulfilling
short-term survival needs to give priority to the environment.
Employing the 2001 World Values Survey, this study analyzes the attitudes of the general
public of South Africa towards environmental matters. These attitudes are contrasted with
those of the elites, who have a disproportionate influence over policy-making, by looking
at the 2000 South African National Leadership Opinion Survey. This study finds that, as
hypothesized, the general population of the country is quite unwilling (or unable) to
contribute materially or financially to environmental improvements, especially in relation
to the elites.
In the final part of the study, these findings are employed in the development of a set of
guidelines that policy-makers can use to increase the probability of developing successful
and effective environmental policies. These guidelines take into account the nature and
dimensions of popular attitudes, and consider ways in which environmental policies can
foster the support of a public that is confronted with so many other serious issues. / AFRIKAANSE OPSOMMING: Suid-Afrika, soos soveel ander ontwikkelende lande, is gekonfronteer met 'n baie
komplekse situasie: alhoewel grootskaalse degradasie van die omgewing die toekoms van
die land bedreig, sien die algemene publiek nie omgewingskwessies as belangrik genoeg
om 'n bydrae te lewer nie. Die argument is dat te veel van die land se bevolking net te
arm of te gefokus is op die bevrediging van kort-termyn oorlewingsbehoeftes om
prioriteit te gee aan omgewingskwessies.
Deur gebruik te maak van die 2001 Wêreld Waardestudie, analiseer hierdie studie die
houdings van die Suid-Afrikaanse publiek teenoor omgewingskwessies. Hierdie houdings
word gekontrasteer met die van die elites, wat 'n disproporsionele invloed het oor die
beleidsmakingsproses, deur gebruik te maak van die 2000 Suid-Afrikaanse Nasionale
Leierskap Opinie Studie. Die studie vind dat, soos gehipotiseer, die publiek onwillig (of
net nie in staat) is om bydrae te lewer tot die oplossing van omgewingskwessies, veral in
vergelyking met die elites.
In die finale afdeling van hierdie studie word die bevindinge gebruik om 'n stel riglyne te
ontwikkel wat deur beleidmakers gebruik kan word om die waarskynlikheid van
suksesvolle en effektiewe omgewingsbeleid te verbeter. Hierdie riglyne neem in ag die
natuur en dimensies van publieke houdings, en bring na vore maniere waardeur
omgewingsbeleide die ondersteuning van 'n publiek, wat gekonfronteer word met soveel
ander ernstige kwessies, kan opbou.
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Comparative impacts of fragmentation on birds in two bioregions in a biodiversity hotspot, the Cape Floristic RegionKieck, Marius Burger 03 1900 (has links)
Thesis (MScConsEcol (Conservation Ecology and Entomology))--University of Stellenbosch, 2009. / Habitat loss and fragmentation are two of the most pressing threats to biodiversity. Avifaunal
diversity and integrity is under immense pressure from these two processes. We have made
major advances in our understanding of avifaunal responses to habitat fragmentation, but mostly
focus on either fragment scale and/or landscape scale influences of fragmentation on birds. A
more comprehensive approach to assessing the impacts of fragmentation was used in this study.
The avifaunas of two different geographical regions and bioregions were surveyed and a multiscale
analysis of avifaunal responses to fragmentation was attempted. The study sites include the
West Coast and East Coast Renosterveld Bioregions in the Cape Floristic Region, South Africa.
Assemblage shifts, feeding guild compositional changes, species abundance variation and species
persistence were examined at the three spatial scales. Time- and distance-restricted point counts
were used to document birds that were directly dependent on the habitat fragments. Forty
fragments were selected in each bioregion and a once-off snapshot of the avifaunal richness and
diversity was obtained.
Results indicate that the avifauna of the two bioregions responded differently to habitat
fragmentation. In the East Coast Renosterveld Bioregion, the assemblages, guild composition
and species abundances were most accurately predicted by landscape configuration. An
assemblage shift occurred at 20 ha fragment area, compared to the 50 ha fragment area threshold
of the West Coast Renosterveld Bioregion’s avifauna composition. In the West Coast
Renosterveld Bioregion, fragment area was the better predictor of assemblage, guild composition
and species abundances. However in both bioregions, the persistence of common species was
equally sensitive to area and landscape scale effects.
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Invertebrate diversity in afrotemperate forests : spatial and seasonal changes and implications for conservation.Uys, Charmaine Janet. January 2006 (has links)
Forests in the Drakensberg Mountains, although generally small and fragmented, represent a wealth of globally significant biodiversity. This is especially true of the invertebrate fauna, which includes a range of localized endemic species. Ground dwelling, flightless invertebrates living in forests show relative immobility and poor dispersal abilities compared to birds, butterflies and other animal taxa. The naturally fragmented state of Afrotemperate forests also geographically isolates these taxa. No quantified, systematic surveys of flightless invertebrates have been conducted in Afrotemperate forests in the Drakensberg Mountains. This means that, to date, invertebrates have not been considered in the management of these habitats. However, invertebrates are vitally important in ecosystem functioning and maintenance and must be included in management plans. This study quantified flightless invertebrate diversity in Afrotemperate forest patches in the Drakensberg by investigating spatial patterns and seasonal changes in invertebrate diversity. The broad objectives were to: 1) Determine the appropriate spatial scale at which conservation of flightless invertebrates should be implemented; 2) Determine which season, taxa and sampling methods are most suitable for biodiversity assessment and monitoring in Afrotemperate forest; and 3) Investigate methods of prioritizing Afrotemperate forests for conservation of flightless invertebrate diversity. Seventeen forest patches in six valleys in four Drakensberg reserves (Rugged Glen Nature Reserve, Royal Natal National Park, Cathedral Peak and Injisuthi) were sampled in the summer of 2004/2005. In addition, three forests at Injisuthi were sampled in March, June, September and December 2004 to enable seasonal comparisons. Sampling methods included soil samples, leaf litter samples, pitfall traps, active search quadrats and tree beats. The study focused on terrestrial molluscs (Class Gastropoda), earthworms (Class Annelida), onychophorans (Class Onychophora), centipedes (Class Chilopoda), millipedes (Class Diplopoda) and ants (Class Insecta). Target taxa were sorted to morphospecies and then identified to species by taxonomic experts. Seventy-two species and a total of 5261 individual specimens from the six target taxa were collected. Species composition of sites varied along the north-south gradient, and species turnover (beta diversity) was related to the distance between sites. Flightless invertebrate species richness and community structure fluctuated seasonally. Therefore, I recommend that sampling should take place during the wet season (summer months). Molluscs were the most suitable taxon among those surveyed to represent flightless invertebrate diversity and leaf litter samples and active search quadrats are the most suitable sampling methods for flightless invertebrates in forest. This study compared approaches to prioritizing Afrotemperate forests in terms of their invertebrate diversity using ranked species richness with complementarity indices of species presence/absence, taxonomic distinctness (orders, families and genera) and endemicity. There was no consistent spatial trend in the priority ranking of forests based on species richness. Complementarity based on species richness only required eight out of 17 forests to represent all 62 species. Although complementarity based on taxonomic distinctness and endemicity required fewer sites, not all species were represented. The minimum set of sites identified using complementarity based on species richness and augmented with information on taxa of conservation importance (local endemic and threatened species) was the most rigorous approach to prioritizing Afrotemperate forest patches in the Drakensberg for flightless invertebrate conservation. Urgent conservation interventions are required because invertebrates play a critical role in ecosystem functioning. As many forest patches and invertebrate populations as possible should be protected to conserve the full complement of invertebrate species of the region. Special management attention should be paid to the eight forests identified as priority sites in the complementarity analyses. Forest patches cannot survive in isolation, so it is important to manage the grassland, riverine vegetation, forest ecotone and forests holistically. Provisional targets were set for the conservation of flightless invertebrates, based on estimates of the requirements for persistence of invertebrates in Afrotemperate forest, made within the constraints of available information and expert opinion. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.
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The effect of habitat alteration by elephants on invertebrate diversity in two small reserves in South Africa.Govender, Navashni. January 2005 (has links)
Balancing increasing elephant numbers with biodiversity conservation in small reserves has
become a concern for many protected area managers. Elephants are considered important
agents of disturbance creating heterogeneity and thus contributing to the maintenance of
biodiversity. However elephants also damage vegetation through their destructive feeding
habits, and this has led to pressure to reduce elephant populations in many reserves.
Quantitative data on the impact of elephants on invertebrates, the main component of
biodiversity at the species level, are lacking.
The aim of this project was to assess the effect that habitat alteration by elephants has
on the diversity of selected ground-dwelling invertebrates (ants, centipedes, millipedes,
spiders, scorpions and termites) through the provision of logs and dung as a potential refuge
niche for these invertebrate communities, and to determine the effect of spatial (vegetation
types) and temporal (season and age of dung) variation on the invertebrates using these
refugia. Variation in impacts was considered important because savanna is not homogenous
and the impact of the refugia is likely to be dynamic in terms of seasonal trends in
invertebrate populations, and in terms of changes in the environmental conditions offered by
the refugia.
Elephant impact on vegetation, quantity of refugia (logs and dung) produced and
invertebrate diversity associated with refugia were determined for 115 transects within
Madikwe Game Reserve in the North Western Province, South Africa. Invertebrate
abundance, species richness and diversity were always higher under refugia than in areas
without refugia. Vegetation utilisation, frequency of refugia production and invertebrate
diversity showed strong temporal variation (seasonal); elephant impact and production of logs
were higher in winter than in summer because elephants are more likely to feed on woody
vegetation in winter when grass nutrient levels are low. Invertebrate diversity under the logs
was higher in summer than in winter, and this probably reflected the higher abundance and
diversity of invertebrates that are usually associated with the warmer, wetter summer months.
The effect of adding refugia to three vegetation types on invertebrate diversity was
tested experimentally at Makalali Private Game Reserve in the Limpopo Province, South
Africa. Logs and elephant dung were set out in five plots each measuring 20m x 20m within
Govender - iii
mixed bushveld, riverine and mopane woodland. Significant differences were observed in
invertebrate abundance, species richness and diversity between the refugia and control plots
that lacked refugia and between the three vegetation types sampled. Similarity between
invertebrate communities utilising the different refugia types and between the three different
vegetation types were tested using the Jaccard similarity coefficient. The three vegetation
types shared fewer than 50% of their species, as did the logs, dung and control sites. However
the results obtained do illustrate a higher degree of similarity between the refugia substrates
(logs and dung) than the control sites and between the more heterogeneous vegetation types
(mixed bushveld and riverine) than the mopane veld. This indicated that invertebrate
communities associated with refugia were not uniform, but were influenced by vegetation
type.
An experimental test of temporal changes in invertebrate community composition
illustrated the importance of elephant dung as a microhabitat for different invertebrate groups
over different ages of dung (three days, two, four, 12 and 32 weeks old). Colonisation of the
dung, by dung beetles was immediate but as the microclimate of the dung changed with time,
the new conditions were ideal for other invertebrate taxa. Over a period of eight months, the
change of invertebrate communities utilising the dung included dung beetles, followed by
millipedes and [mally ant and termite communities.
The results of this study illustrated the importance of refugia (logs and dung) produced
by elephants for ground-dwelling invertebrate species in the savanna environment. The extent
of the influence of the refugia varied both spatially and temporally and this should be
considered in future monitoring or in measuring impacts. While further research on a broader
range of organisms and at larger scales is necessary, elephants do have a positive impact on at
least some components of biodiversity, through the process of facilitation of refugia. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.
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Characterisation of the health, habitat use and movement of adult lowveld largescale yellowfish (Labeobarbus marequensis Smith, 1841) and other fishes in the Crocodile River, Kruger National Park11 September 2013 (has links)
M.Sc. (Aquatic Health) / Yellowfish and specifically Labeobarbus marequensis are a charismatic species targeted by anglers throughout South Africa. Their population are limited to the north-western parts of the country including the lower reaches of the Crocodile River that flows through the Kruger National Park (KNP). Despite conservation efforts the Crocodile River in the KNP is still highly impacted. The effect of these impacts on the ecosystem is largely unknown. The main aim of the study was to determine the influence of changing water quantity and quality in the Crocodile River on adult L. marequensis. This was achieved by evaluating altered flows (discharge) on the behaviour of adult L. marequensis in the Crocodile River using biotelemetry over a two year period. The influence of altered water quality was assessed using metal bioaccumulation as an indicator of metal exposure in L. marequensis, Clarias gariepinus and Hydrocynus vittatus in the Crocodile and Sabie Rivers during a high and low flow season. Biotelemetry was used on 16 L. marequensis and 12 H. vittatus to determine the habitat use and movement responses of the species. Fish were tagged with Advanced Telemetry Systems (ATS) and Wireless Wildlife (WW) tags and tracked remotely and manually. Home ranges were determined using Arc GIS ®, Habitat uses were analyzed using Windows Excel (© 2011, Microsoft inc.). Environment variables recorded were scored as primary and secondary and then combined with a weighting variable 2:1 ratio (primary variable: secondary variable). A mixed-model analysis of variance (ANOVA) approach with a random co-efficients model and Akaike’s information criteria (AIC) were used to test for significance. Analyses were conducted using SAS version 9 (SAS institute, Cary, NC)...
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Evaluation of a U.S. West coast groundfish habitat conservation regulation via analysis of spatial and temporal patterns of trawl fishing effortsBellman, Marlene A. 13 April 2004 (has links)
Recent emphasis on linkages between essential fish habitat and fish stock productivity
has raised concerns about the management of fishing activities such as trawling, which
have the potential to impact fish habitat. Knowing specifically where and how
intensively trawl effort has occurred over time provides ecologists with the necessary
background for habitat impact and recovery studies, and provides fishery managers with
an assessment of how habitat conservation objectives are being met. The objectives of
this study were to (1) examine the extent to which the 2000 Pacific Fishery Management
Council footrope restriction has shifted and reduced trawl fishing effort on Oregon
fishing grounds, (2) to relate these changes in distribution to the benthic habitat type over
which they occur, and (3) to develop methods for enhancing fine-scale spatial review of
targeted fishing effort.
Density analysis of available trawl start locations provided a spatial and temporal
understanding of how fishing efforts increased and decreased in relation to habitat
distribution and fishery management actions between 1995 and 2002. Trawl effort
patterns exhibit significant inter-annual variability and patchy distribution. Areas of
increased fishing effort were still evident between years, despite an overall decline in
trawl tows across the time scale of this study. Tow end point locations for the years
1998-2001 were retrieved from manual logbooks for five reference sites located in the
proximity of rock habitat features. Trawl towlines were mapped from start to end point
and demonstrated a marked enhancement of fine-scale fishing effort resolution, with
increased ability to identify effort shifts over benthic habitat. Distinct spatial shifts in
fishing intensity (measured as km towed) away from rock habitat were evident at all
reference sites, with an average reduction of 86%. Some slight shifts into surrounding
unconsolidated sediments also occurred, indicating effort displacement as well as
reduction. Fishing intensity was calculated from commercial trawl and research trawl
survey towlines to achieve the most accurate assessment of fishing impacts and potential
habitat recovery areas. Research trawling intensity was less than 1% of commercial trawl
effort originating from the same sites. A brief comparison of Oregon vessel towlines and
California vessel towlines demonstrated similar targeted fishing patterns by both fleets,
except at one site.
Results indicate that the footrope restriction, in conjunction with associated landing
limits, was effective in protecting rocky habitats from trawl fishing impacts. Reference
areas were identified where essential fish habitat (EFH) recovery is likely occurring off
the coast of Oregon. Substantial regulatory changes continue in this fishery, with trip
limits and gear restrictions continuously adjusted. Continued monitoring and review of
spatial trawl data would assist in fishery management decision-making and assess
conservation objectives for depleted groundfish and associated habitats. Future research
should incorporate analysis of catch data and expand the review of trawl towlines for the
entire US West coast groundfish fishery. The trawl towline spatial analysis developed in
this work is a credible method for reviewing fishing effort at the scale of the fishery and
in relation to detailed habitat data. The research presented here provides an example of
how an interdisciplinary approach and critical assessment of data can work to resolve
marine management challenges. / Graduation date: 2004
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Ecology and conservation of prairie rattlesnakes (Crotalus viridis viridis) in relation to movement in a fragmented urban environmentAndrus, Wonnita, University of Lethbridge. Faculty of Arts and Science January 2010 (has links)
Eighteen prairie rattlesnakes (Crotalus viridis viridis) were tracked using radio-telemetry and 82
snakes were PIT-tagged over a 2-year period in Lethbridge, AB to determine population size,
movement patterns, and habitat utilization, and to predict fragmentation effects on the species
within an urban locale. Population size was estimated using closed population models at 374
snakes (295 adults) and open population models at 204 snakes (161 adults), greater than an
estimate of <50 adults in 2003 (Ernst, 2003) and 2006 (Ernst & Quinlan, 2006).
Mean home range sizes, based on 95% minimum convex polygon analysis, differed significantly
between years (31.51 ha in 2005, 3.72 ha in 2006). Calculated movement parameters, such as
mean distance moved per day, total distance moved over the course of the active season, and
frequency of movement varied between years and individuals. Greater-than-expected (under
hypotheses of even habitat choice) utilization was observed in habitat types located within coulee
and flood plain areas, with apparent preference towards unbroken parcels of grassland or
cottonwoods, whereas less-than-predicted utilization of agricultural habitat type was observed.
Fragmentation effects on prairie rattlesnake movement and occurrence were examined through
modeling and were found to coincide with observed species’ locations, suggesting that prairie
rattlesnakes are undergoing modification of movement patterns to avoid highly concentrated
human density or use. Influence of weather on the use of vegetative ground cover was observed,
as it was accessed more by prairie rattlesnakes at higher temperatures.
Recommendations towards future management of the prairie rattlesnake population in Lethbridge
are given, including protection of the Bridge View Drive site and inclusion of varied habitat types
and terrain when planning habitat and wildlife corridors. Management decisions that ensure
remaining habitat parcels and connective areas near rattlesnake foraging or movement corridors
are also advocated. Identification of future research focuses include studies on juvenile
survivorship, genetic structure, and vehicle-related mortality. / xii, 83 leaves : col. ill., col. maps ; 29 cm
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A changing cultural landscape Yanchep National Park, Western Australia /Venn, Darren Peter. January 2008 (has links)
Thesis (M.A.)--Edith Cowan University, 2008. / Submitted to the Faculty of Education and Arts. Includes bibliographical references.
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