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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.
131

Invasive alien species and the protection of biodiversity: the role of quarantine laws in resolving inadequacies in the international legal regime

Riley, Sophie, Law, Faculty of Law, UNSW January 2008 (has links)
The problem of invasive alien species (IAS) is recognized as the second most serious threat to loss of biodiversity after habitat destruction. It is a problem largely created by humans as they transport and introduce species, deliberately and accidentally, from one part of the globe to another. The pressures exerted on biodiversity by international trade are one of the most serious aspects of the IAS problem. Although states are under obligations in international environmental law to prevent the entry of, and control, those alien species that threaten biodiversity, to date state practice has often been found wanting. In particular, quarantine regulation, which can be a state??s first line of defence against IAS, is mainly used by states to protect their farming and agricultural product sectors rather than biodiversity at large. The reasons for this include lack of domestic resources and lack of guidance at the international level. However, even if states were to expand the purview of quarantine, the question arises whether they would be able to use quarantine regulation to protect biodiversity from IAS while simultaneously fulfilling their international trade law obligations. This study seeks to answer this question by examining international environmental law and international trade law in their application to quarantine regulation. In doing so, the study identifies many areas of conflict. The different policies that underpin environmental and trade regimes mean that environmental concepts, such as the precautionary principle and the ecosystem approach, are difficult to apply within the international trade law regime. A way of achieving a more harmonized international response to the problem of IAS is suggested by incorporating environmental considerations into the international standards used by states to design and implement domestic quarantine measures. To facilitate the practical implementation of international standards the study further recommends appropriate financial and institutional capacity building mechanisms.
132

The role of non-indigenous benthic macrofauna in the diet of snapper (Pagrus auratus)

Dodd, Suzannah January 2009 (has links)
Snapper, Pagrus auratus is a valuable coastal fish species in New Zealand and forms an important commercial and recreational fishing industry in the north-east of New Zealand. Previous studies revealed evidence that this carnivorous, primarily benthic feeder consumes a non-indigenous macrobenthic species. Many non-indigenous macrobenthic species have now become established in New Zealand waters. For example, in Rangitoto Channel, Hauraki Gulf, non-indigenous macrobenthic species are prolific, with three bivalve species in particular having thriving populations: Limaria orientalis, Musculista senhousia, and Theora lubrica. The role of these species in the diet of snapper, however, is unknown. To assess the availability of indigenous and non-indigenous prey species to snapper, benthic macrofaunal assemblages throughout Rangitoto Channel were surveyed. To do so, sediment samples were collected at 84 sites. At 24 of these sites sediment was also collected for grain size analysis and at 40 of these sites the seafloor was surveyed with video. To investigate the diet of snapper, fish were collected from four monitoring sites within the channel. Bimonthly monitoring of the diet of snapper as well as the benthic macrofauna was completed at these monitoring sites and trends in the abundance of three prey species, two of which were non-indigenous species, within the sediment and the diet of snapper were compared from June to December 2008. A detailed description of the benthic macrofaunal assemblages throughout Rangitoto Channel confirmed that three non-indigenous species are established throughout this area. The analyses revealed that the diet of snapper has shifted compared to previous studies. Snapper now consume large quantities of two non-indigenous species, M. senhousia and L. orientalis. Consumption of the former species apparently results from its dominance and biomass within the sediment. It is therefore not surprising that snapper consumed large amounts of this species. In contrast, L. orientalis occurred disproportionately in the diet of snapper compared to its abundance within the sediment. I suggest that the establishment of some non-indigenous species benefits snapper.
133

The role of non-indigenous benthic macrofauna in the diet of snapper (Pagrus auratus)

Dodd, Suzannah January 2009 (has links)
Snapper, Pagrus auratus is a valuable coastal fish species in New Zealand and forms an important commercial and recreational fishing industry in the north-east of New Zealand. Previous studies revealed evidence that this carnivorous, primarily benthic feeder consumes a non-indigenous macrobenthic species. Many non-indigenous macrobenthic species have now become established in New Zealand waters. For example, in Rangitoto Channel, Hauraki Gulf, non-indigenous macrobenthic species are prolific, with three bivalve species in particular having thriving populations: Limaria orientalis, Musculista senhousia, and Theora lubrica. The role of these species in the diet of snapper, however, is unknown. To assess the availability of indigenous and non-indigenous prey species to snapper, benthic macrofaunal assemblages throughout Rangitoto Channel were surveyed. To do so, sediment samples were collected at 84 sites. At 24 of these sites sediment was also collected for grain size analysis and at 40 of these sites the seafloor was surveyed with video. To investigate the diet of snapper, fish were collected from four monitoring sites within the channel. Bimonthly monitoring of the diet of snapper as well as the benthic macrofauna was completed at these monitoring sites and trends in the abundance of three prey species, two of which were non-indigenous species, within the sediment and the diet of snapper were compared from June to December 2008. A detailed description of the benthic macrofaunal assemblages throughout Rangitoto Channel confirmed that three non-indigenous species are established throughout this area. The analyses revealed that the diet of snapper has shifted compared to previous studies. Snapper now consume large quantities of two non-indigenous species, M. senhousia and L. orientalis. Consumption of the former species apparently results from its dominance and biomass within the sediment. It is therefore not surprising that snapper consumed large amounts of this species. In contrast, L. orientalis occurred disproportionately in the diet of snapper compared to its abundance within the sediment. I suggest that the establishment of some non-indigenous species benefits snapper.
134

The introduced Australian oyster blenny, Omobranchus anolius

Barker, Jeremy James January 2009 (has links)
In 2003, an intertidal fish, the Australian oyster blenny (Omobranchus anolius) was discovered in Auckland, New Zealand. Subsequent surveys of the inner Hauraki Gulf found only 24 specimens, the majority of which (n=20) occurred at a single location within Tamaki River. Most non-indigenous species do not establish viable populations, few of those that do spread; even fewer become abundant and widespread and have negative ecological impacts. Little was known about the ecology of this fish, it was unclear whether it would establish and spread in New Zealand, and in the event it did, what effect it would have on native flora and fauna.
135

Effects of Microstegium vimineum (Trin.) A. Camus (Asian stiltgrass; Poaceae) on native hardwood seedling growth and survival

Jacques, Rochelle R. January 2007 (has links)
Thesis (M.S.)--Ohio University, June, 2007. / Title from PDF t.p. Includes bibliographical references.
136

Impacts of deer and honeysuckle on the endangered Trillium reliquum and its associated plant community

Thompson, Jacob Seth. January 2007 (has links) (PDF)
Thesis (M.S.)--Georgia Southern University, 2007. / "A thesis submitted to the Graduate Faculty of Georgia Southern University in partial fulfillment of the requirements for the degree Master of Science." Under the direction of Lissa M. Leege. ETD. Electronic version approved: May 2007. Includes bibliographical references (p. 92-101)
137

Consequences of weed invasion and control on plant-bird interactions and bird communities

Gosper, Carl R. January 2004 (has links)
Thesis (Ph.D.)--University of Wollongong, 2004. / Typescript. Includes bibliographical references: p. 169-180.
138

Determinants of native and non-native plant distributions in a temperate forest understory

Gilbert, Benjamin, January 1900 (has links)
Thesis (M.Sc.). / Written for the Dept. of Biology. Title from title page of PDF (viewed 2008/07/24). Includes bibliographical references.
139

A Panax-centric view of invasive species and a case study on the effects of garlic mustard (Alliaria petiolata)

Wixted, Kerry Lynn. January 2009 (has links)
Thesis (M.S.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains vi, 98 p. : ill., map. Vita. Includes abstract. Includes bibliographical references.
140

A cryptic invasion of the non-native Siberian elm (Ulmus pumila) to Southwest Missouri /

Ladd, Megan E., January 1900 (has links)
Thesis (M.S.)--Missouri State University, 2008. / "May 2008." Includes bibliographical references (leaves 28-31). Also available online.

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