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Phylogeography of Southeast Asian seahorses in a conservation contextLourie, Sara Anne January 2004 (has links)
This thesis investigates the potential role of historical isolation of ocean basins in promoting diversification among marine organisms in Southeast Asia. It also questions the possible effects of Pleistocene exposure of the Sunda Shelf on present day marine distributions and genetic diversity. Four species of exploited seahorses (genus Hippocampus), with differing ecological parameters, are used to test historical hypotheses. The results (based on cytochrome b DNA sequencing) suggest that significant phylogeographic structure does exist among seahorse populations in Southeast Asia, but that the patterns are only partially concordant across species. Distinct phylogeographic breaks are seen in H. barbouri, H. kuda, and H. trimaculatus, whereas greater spatial overlap of haplotypes in H. spinosissimus indicates more extensive gene flow. The phylogeographic history of the two shallow water species (H. barbouri and H. kuda) appears to have been primarily shaped by fragmentation and/or long-distance colonisation events. Both species show patterns consistent with hypotheses of divergence mediated by ocean basins separations. The deeper water species (H. spinosissimus and H. trimaculatus) show more evidence of range expansion and isolation by distance. Hippocampus trimaculatus shows a deep east-west phylogeographic division at right angles to that predicted by the separation of the Indian versus Pacific Ocean basins and instead parallels the terrestrial division known as Wallace's Line. Different species have also responded differently to the reflooding of the Sunda Shelf at the end of the last Ice Age: the two deeper water species have colonised it extensively suggesting limited barriers to movement, whereas the shallow water species have not. It is possible that the populations of H. kuda now inhabiting the shelf may stem from populations that found refuge in brackish water lakes when the shelf was exposed to the air. All four species are heav
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The phylogeographic history of the wood frog (Rana sylvatica) /Lee-Yaw, Julie A. January 2006 (has links)
Although the range dynamics of North American amphibians during the last glacial cycle are increasingly better understood, the recolonization history of the most northern regions and the impact of southern refugia on patterns of genetic diversity in these regions are not well reconstructed. In this study I present the phylogeographic history of a widespread and primarily northern frog, Rana sylvatica. For this study, 45 individuals from 34 localities were surveyed for a 700 b p. fragment of cytochrome b and 551 individuals from 116 localities were surveyed for 650 b.p. of the NADH dehydrogenase subunit 2 and tRNATRP mitochondrial genes. Phylogenetic analyses revealed two distinct clades corresponding to eastern and western populations. Phylogeographic patterns within each of these clades revealed similarities as well as differences from patterns found in other species. Specifically, the results corroborate eastern refugia located in the southern Appalachians near present-day North and South Carolina and in the interior plains in the lower Ohio River Valley. Current Maritime populations form a subclade amongst eastern populations and appear to have been colonized from the southern refugium. However, a more northern refugium located in the Appalachian highlands seems to have been source for most other northeastern wood frog populations. Rana sylvatica populations in the Great Lakes region appear to have been colonized from a western refugium located in present-day Wisconsin. This refugium was also a likely source for populations in the species' expansive northwestern range since there is no evidence to support additional, more western refugia.
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Predicting bat occurrence in northern California using landscape-scale variablesDuff, Andrew A. January 2004 (has links)
Predicting species occurrence based upon landscape-scale characteristics is a fundamental goal of ecology and conservation biology. Accurately predicting the potential occurrence of a species is fundamental to management activities that involve large areas where sampling is difficult due to logistical or financial constraints. During the summers of 2001-2003 mist nets were used to capture bats in Whiskeytown National Recreation Area (WNRA), Lassen Volcanic National Park (LVNP), and Lassen National Forest (LNF) in northern California. I used logistic regression and Akaike's Information Criterion (AIQ to model species distributions. Models developed a priori were used to determine which variables best discriminated between capture sites and non-capture sites. Prediction models were mapped using Geographic Information Systems. In WNRA, for all bat species combined total edge was most parsimonious, whereas in LVNP elevation was best for all species. Elevation and tree size were important in predicting the occurrence of pallid bats (Antrozous pallidus), in LNF. Results of this study are important to wildlife managers within the study areas because the models can be used to minimize deleterious impacts on bats. Moreover, distribution maps are valuable to bat conservation efforts because they provide baseline data important for evaluating and predicting population responses to management activities. / Department of Biology
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The influence of turbidity on fish distribution in Natal estuaries.Cyrus, Digby Paul. January 1984 (has links)
Studies In other parts of the world have proved that
turbidity affects aquatic life and work In Australia and
North America has shown that the distribution of some fish
species may be determined by the level of turbidity present.
This, coupled with the fact that: (i) Natal estuaries are
important as nursery areas for the juveniles of many marine
fish species, (ii) the estuaries exhibit a wide range of
turbidities and (iii) little was known of the effects of
turbidity on the fish populations in estuaries, led to this
study being undertaken.
Turbidity and its effects on fish distribution In
Natal estuaries was investigated from January 1980 to June
1983. Lake St. Lucia, which is predominantly turbid but also
has clear water areas, was the main study area. Six other
estuarine systems sampled were chosen to cover a wide range
of estuarine types and turbidities. Field sampling was
undertaken to determine which species were present under
different turbidities, simultaneously physical factors which
were potentially affecting fish distribution were also
monitored. In addition to this, laboratory equipment which
enabled a turbidity gradient to be established In a choice
chamber tank was used to test the turbidity preferences of 10
common estuarine species for which field data were available.
These tests allowed the elimination of all physical factors
except turbidity.
Of the physical parameters monitored In the field,
turbidity, temperature and food availability In the benthos,
were determined as being important In affecting fish
distribution within estauries. However, comparison of fish
distribution data for twenty species, with these factors
showed that turbidity was exerting the major influence. It
was also found that fish species occurred In one of five
groups, inhabiting either clear, 'clear to partially turbid',
intermediate or turbid waters or they were indifferrent to
turbidity. Laboratory results for eight of ten species tested
showed significant aoreement with the field data. The results of this study have shown that turbidity is
the most important factor determining the distribution of
juvenile marine fish In estuaries and that the greatest
number of species are present in , waters which are not clear.
The attraction to and presence in such systems appears to be
related to the fact that turbid estuaries 'provide protection
from fish and bird predators while also acting to reduce
intraspecific predation. Of factors attracting juvenile fish
into estuaries, turbidity is probably the single most
important acting in this respect. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1984.
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Revision of the taxonomy and distribution of the African millipede genera Bicoxidens, Spirostreptus, Plagiotaphrus and Archispirostreptus (Diplopoda, Spirostreptida, Spirostreptidae)Mwabvu, Tarombera. January 2010 (has links)
No abstract available. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.
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Availability of registered pharmaceutical structures in South Africa : 2003 until 2008 / Ridovhusanae RabaliRabali, Ridovhusanae January 2009 (has links)
Despite the deteriorated state of health care in South Africa, the government remains
committed to realising the right of every citizen to access health care, including good, quality
and essential drugs. In recognising the availability of pharmaceutical facilities as a major
component of access to health care, and the previous imbalances in the distribution of
pharmaceutical structures and services, laws pertaining to the licensing and ownership of
pharmacies were amended and promulgated in 2003 to address the distribution problem. In
addition, regulations relating to a transparent priCing system on medicines and related
sUbstances were introduced in 2004. These, coupled with factors influencing the choice of a
pharmacy location, and the deficiencies in human resourges exercising an impact on both
pharmacy and other health care personnel, have influenced the distribution and availability
of pharmaceutical structures in South Africa from the year 2003 to 2008.
OBJECTIVE:
The main objective of this study was to investigate the availability and distribution of
pharmaceutical structures registered with the South African Pharmacy Council, in South
Africa, as of 2003 until 2008.
METHOD:
Data on the total number and geographical distribution of registered pharmaceutical
structures in South Africa were obtained from the South African Pharmacy Council's register
of pharmacies of August 2003, 2004, 2005, 2006, 2007 and 2008. The registered
pharmaceutical structures were categorised according to their nature of services to the
patient into "direct service" and "indirect service" (support) pharmacies. Availability was
taken to refer to the actual presence of the pharmaceutical structures in relation to the
demand for the services and measured quantitatively using population: provider ratios. The
'population' for indirect service pharmacies was taken as the direct service pharmacies and,
the 'population' for direct seNice pharmacies was taken as the estimated population of the
different geographical regions.
RESULTS:
The results revealed a 12% increase in the total number of registered pharmaceutical
structures between the study years, to a total of 4227 pharmaceu'tical structures in 2008.
Gauteng was identified as the province with the highest number of registered pharmaceutical
structures, while the Northern Cape province contained the lowest number of registered
pharmaceutical structures throughout the entire study period. The percentage of
municipalities without any registered pharmaceutical structures decreased from 23% in 2003
to 19% in 2008.
The indirect seNice pharmacies constituted 14% of the total number of registered
pharmaceutical structures in South Africa. Most of these structures were situated in the
province of Gauteng throughout the study period. National availability of these structures
only improved for the manufacturing pharmacies.
The registered direct seNice pharmacies increased by 13.2% to total 3642 pharmacies in
2008. Approximately 20% of the municipalities in the country (respectively 5.5% of the
population) did not contain any registered direct seNice pharmacy in 2008. Most of these
municipalities were situated in the KwaZulu-Natal province. The province of Gauteng
contained the highest proportion (32%) of the direct seNice pharmaceutical structures. The
decrease in the pharmacy per population ratio of the structures from 1: 14 547 people in
2003 to 1: 13 615 people in 2008 indicated an improvement in the availability of the
structures. However, the improved availability did not take effect within each province as the
Northern Cape, Mpumalanga and Gauteng provinces experienced an increase in the
pharmacy per population ratio.
CONCLUSION:
The availability of registered pharmaceutical structures in South Africa improved between
2003 and 2008. However, the distribution of these structures remains geographically uneven
and inequitable to the population of the country. / Thesis (M.Pharm. (Pharmacy Practice))--North-West University, Potchefstroom Campus, 2010.
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Availability of registered pharmaceutical structures in South Africa : 2003 until 2008 / Ridovhusanae RabaliRabali, Ridovhusanae January 2009 (has links)
Despite the deteriorated state of health care in South Africa, the government remains
committed to realising the right of every citizen to access health care, including good, quality
and essential drugs. In recognising the availability of pharmaceutical facilities as a major
component of access to health care, and the previous imbalances in the distribution of
pharmaceutical structures and services, laws pertaining to the licensing and ownership of
pharmacies were amended and promulgated in 2003 to address the distribution problem. In
addition, regulations relating to a transparent priCing system on medicines and related
sUbstances were introduced in 2004. These, coupled with factors influencing the choice of a
pharmacy location, and the deficiencies in human resourges exercising an impact on both
pharmacy and other health care personnel, have influenced the distribution and availability
of pharmaceutical structures in South Africa from the year 2003 to 2008.
OBJECTIVE:
The main objective of this study was to investigate the availability and distribution of
pharmaceutical structures registered with the South African Pharmacy Council, in South
Africa, as of 2003 until 2008.
METHOD:
Data on the total number and geographical distribution of registered pharmaceutical
structures in South Africa were obtained from the South African Pharmacy Council's register
of pharmacies of August 2003, 2004, 2005, 2006, 2007 and 2008. The registered
pharmaceutical structures were categorised according to their nature of services to the
patient into "direct service" and "indirect service" (support) pharmacies. Availability was
taken to refer to the actual presence of the pharmaceutical structures in relation to the
demand for the services and measured quantitatively using population: provider ratios. The
'population' for indirect service pharmacies was taken as the direct service pharmacies and,
the 'population' for direct seNice pharmacies was taken as the estimated population of the
different geographical regions.
RESULTS:
The results revealed a 12% increase in the total number of registered pharmaceutical
structures between the study years, to a total of 4227 pharmaceu'tical structures in 2008.
Gauteng was identified as the province with the highest number of registered pharmaceutical
structures, while the Northern Cape province contained the lowest number of registered
pharmaceutical structures throughout the entire study period. The percentage of
municipalities without any registered pharmaceutical structures decreased from 23% in 2003
to 19% in 2008.
The indirect seNice pharmacies constituted 14% of the total number of registered
pharmaceutical structures in South Africa. Most of these structures were situated in the
province of Gauteng throughout the study period. National availability of these structures
only improved for the manufacturing pharmacies.
The registered direct seNice pharmacies increased by 13.2% to total 3642 pharmacies in
2008. Approximately 20% of the municipalities in the country (respectively 5.5% of the
population) did not contain any registered direct seNice pharmacy in 2008. Most of these
municipalities were situated in the KwaZulu-Natal province. The province of Gauteng
contained the highest proportion (32%) of the direct seNice pharmaceutical structures. The
decrease in the pharmacy per population ratio of the structures from 1: 14 547 people in
2003 to 1: 13 615 people in 2008 indicated an improvement in the availability of the
structures. However, the improved availability did not take effect within each province as the
Northern Cape, Mpumalanga and Gauteng provinces experienced an increase in the
pharmacy per population ratio.
CONCLUSION:
The availability of registered pharmaceutical structures in South Africa improved between
2003 and 2008. However, the distribution of these structures remains geographically uneven
and inequitable to the population of the country. / Thesis (M.Pharm. (Pharmacy Practice))--North-West University, Potchefstroom Campus, 2010.
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Systematic and phylogeographic implications of molecular variation in the western North American roseroot, Rhodiola integrifolia (Crassulaceae)Guest, Heidi J. 26 May 2010 (has links)
The roseroot genus Rhodiola is widely distributed in arctic and alpine areas of the
Northern Hemisphere. It is most speciose in the high mountain ranges of central Asia.
Rhodiola integrifolia occurs at high altitudes and high latitudes in western North America and northeastern Asia. During the Pleistocene glaciations the region between Asia and North America known as Beringia was ice free and acted as a glacial refugium for coldadapted taxa. I surveyed variation in a nuclear (ITS) and chloroplast (psbA-trnH spacer) DNA region in R. integrifolia and its North American relatives, R. rosea and R. rhodantha. Phylogenetic analyses based on ITS showed that (i) the western North American species R. integrifolia and R. rhodantha are distinct but closely related sister taxa; and (ii) these two species and the eastern North American R. rosea belong to
separate clades within Rhodiola. Analyses of the plastid region showed that although the
sister species R. integrifolia and R. rhodantha are distinct, some populations sampled in the southern Rocky Mountains (where the two species overlap) share psbA-trnH haplotypes, suggesting that they hybridized at some time in the past. Within R. integrifolia, both nuclear and plastid DNA regions showed strong north-south patterns of differentiation, a pattern consistent with western North America’s glacial history.
Restriction site analysis and sequencing of the plastid psbA-trnH spacer region from
samples from 66 populations of R. integrifolia revealed 12 restriction-site haplotypes and 28 sequence haplotypes. A few of the sequence haplotypes were widely distributed, but most were relatively localized. Of the localized haplotypes, 10 were exclusively Beringian and an additional four were found along the northern boundary of glaciation (at the last glacial maximum) in the Yukon and Alaska; two haplotypes were found in northern coastal BC (Queen Charlotte Islands and adjacent mainland), in the vicinity of possible glacial refugia on the Queen Charlotte Islands. Only five haplotypes occurred exclusively south of the glacial maximum. Haplotype diversity in R. integrifolia decreased toward the south. Populations north of 60 N contained 21 (75%) of the 28 sequence haplotypes, and often contained multiple restriction-site haplotypes. Populations south of that latitude contained a total of only 13 restriction haplotypes, and were usually monomorphic for restriction-site haplotypes. Phylogenetic analyses of R. integrifolia plastid DNA sequences supported a hypothesis of southward spread from Alaska, and suggested that two to three clades of R. integrifolia independently migrated
southward in western North America.
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Geomorphic controls on the distribution of Atlantic salmon (Salmo salar) habitat in two contrasting fifth-order streams in the Gaspe Peninsula, Quebec : the Petite Cascapedia and Bonaventure riversCoulombe Pontbriand, Moise. January 2001 (has links)
Although the watersheds of the Petite Cascapedia and Bonaventure Rivers, Gaspe Peninsula, have broadly similar geology and land use, their segment-scale river geomorphology is contrasted by subtle differences in valley characteristics that are a legacy of their individual geomorphic histories. These differences have consequences on the distribution of Atlantic salmon habitat such as boulder abundance (for parr rearing and overwintering habitats) and spawning substrate quality. Parr preference for boulder-rich river segments (1--5 km) was observed in the Bonaventure River. In the study systems redd distribution was sensitive to relatively small changes in the fines content of riffle substrate. River segments flowing through moderately narrow semi-alluvial valleys present better overall parr habitat (high boulder abundance) and better spawning substrate quality (percentage of sand) than wider valley sections. These differences are due to additional sources of coarse sediment, higher shear stresses, and lower bank erosion rates in such valleys.
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Data requirements for the establishment of protected area networksTaylor, Kevin. January 2000 (has links)
An analysis of the impact of incomplete species distribution information on our capacity to identify minimum size protected area networks was performed. Using bird distribution data for southern Quebec it was found that efficient protected area networks could be established using incomplete distribution information, as little as 30%. The results also revealed that reserve networks encompassing the majority of the biodiversity could be established using as little as 10% of the information. The key to producing efficient networks is the ability of the selection algorithm to identify complementary sets of sites in terms of species composition. The results reveal that the algorithm can best accomplish this when the data set used is produced using a geographically intensive site-based survey approach. The results were consistent over three data sets, the original and two modified, indicating that they are transferable to geographic areas and species groups with differing species distribution characteristics.
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