Thesis (Ph.D.)--Murdoch University, 2003. / Appendix 1 attached as CD-ROM. Thesis submitted to the Division of Science and Engineering. Bibliography: leaves [156]-173.

Thesis (Ph.D.)--Baylor University, 2008. / Includes bibliographical references (p. 80-86)

Thesis (M.S.)--University of Nevada, Reno, 2008. / "May, 2008." Includes bibliographical references (leaves 25-30). Online version available on the World Wide Web.

Thesis (M.A.G.)--Texas State University-San Marcos, 2004. / Vita. Appendices: leaves 269-302. Includes bibliographical references (leaves 303-318).

Thesis (M.A.G.)--Texas State University-San Marcos, 2004. / Vita. Appendices: leaves 269-302. Includes bibliographical references (leaves 303-318).

Thesis (Ph. D., Natural Resources)--University of Idaho and Centro Agronómico Tropical de Investigación y Enseñanza, December 2007. / Major professors: Brian Kennedy and Celia Harvey. Includes bibliographical references. Also available online (PDF file) by subscription or by purchasing the individual file.

Thesis (M.S.)--University of California, Santa Cruz, 1995. / Typescript. Includes bibliographical references (leaves 126-130).

Thesis--Wisconsin. / Vita. Includes bibliographical references (leaves 185-195).

The studies on the Vaal River and its tributaries presented here, were carried out for a variety of reasons. Prominent among them were several of immediate practical importance, such as the need to know the pollution status of waters which ultimately form the major supply for the Witwatersrand urban and industrial complex, and the need for background data on a stretch of the river which was to be insecticided to control a Simulium pest. However the results of such work can often be used for wider purposes. In this thesis they are used to examine the major factors thought to govern the distribution and abundance of the invertebrate Metazoa in the river. Introduction, p. 2-3.

An estuary can be defined as a partially enclosed, coastal body of water which is either permanently or periodically open to the sea and within which there is a measurable variation of salinity due to the mixture of sea water with fresh water derived from land drainage. Estuaries are extremely important environmental assets and the management of them is dependent on the active involvement of the people whose livelihoods depend on them. There have been steady decreases in freshwater inflows into them during the past century due to abstraction of river water for human consumption and alien tree and plant infestations. Due to these decreases in freshwater inflows, many estuaries have become smaller and are providing reduced recreational services to users, such as boaters, fishermen and birders. This reduction in recreational service provision has adverse economic consequences. The scale of these consequences have become of great interest to river catchment planners. Of particular interest is the value of the freshwater inflows into estuaries relative to other abstractions of this water. The value referred to here is in terms of the environmental services yielded to recreational users. From a management perspective, it is desirable that these marginal values be compared with marginal cost values of this water in its best alternative use in order to guide the allocation of inflows into the respective estuaries. The aim of this study is to place a monetary value on this freshwater inflow at the Kowie, Kromme and Nahoon estuaries. Due to the fact that the freshwater flowing into estuaries is not a traded good, an alternative method to market price must be used to value it. The method of valuation used in this study is the contingent valuation method. The contingent valuation method (CVM) is a survey technique which asks individuals to place values upon changes to environmental assets. The questionnaires used in the surveys differed slightly. The one administered at the Nahoon Estuary was revised in the light of experience gained at the administration of the ones at the Kowie and the Kromme estuaries. Some questions in the latter two surveys were found to be confusing to the respondents and were made clearer and some of the questions were found to yield little extra information and were scrapped from the Nahoon Estuary survey.