Thesis (Ph. D.)--Université de Nantes, 1970. / On cover: "Travaux du Laboratoire de geologie marine, Faculté des sciences de Nantes, 1970." At head of title: N ̊C.N.R.S.A.O. 48-52. Includes bibliographical references (p. 107-122).

Thesis (Doctoral)--University de Nante, 1986. / Abstract also in English. Includes bibliographical references (leaves 183-189).

Thesis (Ph. D.)--North Carolina State University, 1985. / Vita. Includes bibliographical references (p. 66-67).

Thesis (PhD--Marine Science)--University of Auckland, 2009. / " A thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Marine Science." Includes bibliographical references (leaves 161-173).

Thesis (Ph.D.) - University of St Andrews, May 2008.

Thesis (Ph.D. (Zoology & Entomology)) - Rhodes University, 2007.

Thesis (Ph.D.)--University of Delaware, 2007. / Principal faculty advisor: K. Eric Wommack, Dept. of Plant & Soil Sciences. Includes bibliographical references.

Thesis (M. Sc.)--University of Canterbury, 2006. / Typescript (photocopy). Includes bibliographical references (leaves 116-138). Also available via the World Wide Web.

Thesis (M.S.) OGI School of Science & Engineering at OHSU, June 2007. / Includes bibliographical references (leaves 136-140).

The ecologist Garrett Hardin (1968) introduced a useful concept called the tragedy of the commons, which describes how ecological resources become threatened or lost. The term “commons” is based on the commons of old English villages and is symbolic of a resource that is shared by a group of people. If every person were to use each resource in a sustainable fashion it would be available in perpetuity. However, if people use more than their share they would only increase their personal wealth to the detriment of others. In addition, an increase in the population would mean that the size of each share would have to decrease to accommodate the larger number of people. As a result, resources are threatened by personal greed and uncontrolled population growth. Freshwater is an example of a common resource that is under threat in South Africa where the average annual rainfall is less than 60 percent of the global average (Mukheibir & Sparks 2006). The increasing demands for freshwater as well as its eutrophication are major concerns with regards to estuarine health, environmental resource management and human health. The correct management of water is necessary to ensure that it is utilised in a sustainable manner. The National Water Act (No. 36 of 1998) has provided the rights to water for basic human needs and for sustainable ecological function; the Basic Human Needs Reserve and Ecological Reserve are both provided as a right in law. The amount of water necessary for an estuary to retain an acceptable ecological status, known as the Estuarine Ecological Reserve, is determined through the implementation of procedures (rapid, intermediate or comprehensive) compiled by the Department of Water Affairs and Forestry (1999) in its Resource Directed Measures (RDM) for the Protection of Water Resources. The impact of restricted flow on estuaries can be reduced by manipulating the water released from impoundments, the regulation of water abstractions within the river catchment or both (Hirji et al. 2002). The reserve assessment method is designed to evaluate ecosystem requirements by employing groups of specialists from different disciplines. In South Africa, this includes hydrologists, sedimentologists, water chemists and biologists (including microalgae specialists). The use of microalgae in ecological assessments has largely been based on research that was initiated at the Nelson Mandela Metropolitan University (formerly University of Port Elizabeth) and subsequently at Rhodes University (Grahamstown) and the University of KwaZulu Natal (Durban). The microalgal research can be divided into two main focus areas; phytoplankton and benthic microalgae