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Easy Identification of The Most Common Freshwater Algae A Guide for The Identification of Microscopic Algae in South African Freshwaters

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The National Water Act (Act 36 of 1998) gave the Department of Water Affairs and Forestry (DWAF) the responsibility to develop National Monitoring Programmes, of which the National Eutrophication Programme (NEMP) is but one. During the development and implementation of the NEMP in 2000, it was identified that there is a need to increase the algal identification capacity in South Africa and to report on problems associated with eutrophication.

Information used to understand the quality of South African freshwater resources can be deduced from the algal composition. The use of diatom indices is gaining popularity and is considered to be a feasible option for the reporting of the eutrophication status of rivers. Identification of algae is a skill valued by, amongst others, the academic world, water purification institutions and governmental organisations whose operators are concerned with the presence of possible taste-, odour-, filter-clogging or toxin-producing algae in their source water. Besides this, the presence of algae contributes to the high cost of water purification. Excessive cyanobacterial blooms produce toxins that can be a serious risk to human health if not treated with caution and the necessary knowledge (WHO 1999).

During the last ten years a number of events in South Africa have led to increased awareness of algae, particularly cyanobacteria (Harding & Paxton 2001; Downing & Van Ginkel 2002). The Hartbeespoort Dam is one of the best known cyanobacterial bloom hazards both nationally and internationally. Many impoundments, e.g. the Haaempoort, Bon Accord, Bospoort, Bronkhorstspruit, Klipvoor, Rietvlei, Roodeplaat and Voelvlei Dams, are known to have a trophic status between eutrophic and hypertrophic, and can, therefore, experience algal and cyanobacterial blooms on a large scale (Van Ginkel et al. 2001a). Furthermore, noxious cyanobacterial blooms have spread to freshwater systems where no previous problems have been reported. The Orange River has experienced cyanobacterial blooms on an annual basis since the year 2000. High flow conditions have flushed a new invader species, Cylindrospermopsis raciborskii, down the lower Orange River (Van Ginkel & Conradie 2001). There are also reports of increased Ceratium hirundinella blooms in freshwater resources of South Africa (Van Ginkel et al. 2001 b).

The tremendous impact (including potential health impacts) that algal blooms may have on agriculture, recreation and the drinking water industry, is one of the major reasons for the development of this guide.

There is a drive within DWAF to improve on the knowledge of algal composition in dams and rivers in order to provide information to management through the National Eutrophication Monitoring Programmes (NEMP) and the National Aquatic Ecosystem Health Monitoring Programme (NAEHMP, formerly known as the RHP).

Freshwater algae are fascinating and diverse living organisms and another purpose of this book is to provide readers with a photo guide to the most common genera of South African freshwater algae. This guide focuses primarily on freshwater phytoplankton and excludes many genera that occur largely in soil or aerial habitats. Identification of algae can be difficult since most are quite small and, therefore, require high-powered microscopes, together with the correct techniques to observe their distinguishing features. The text in the book is divided into seven main algal groups, and combines information on taxonomical characteristics, dimensions, the ecology and problems associated with the 78 genera. Colour images provide the reader with an additional reference source and identification tool.

This photo containing booklet has been prepared to provide students, less experienced and experienced professional aquatic biologists with a means to identify some of the more commonly encountered freshwater algal genera of South Africa. While technical termwere avoided as far as possible, a simple glossary was includ We meaning of essential terminology.

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Ketersediaan

Informasi Detail

Judul Seri

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No. Panggil

579.8 SAN e

Penerbit

Potchefstroom : North - West University., 2006

Deskripsi Fisik

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Bahasa

English

ISBN/ISSN

0-621-35471-6

Klasifikasi

579.8

Tipe Isi

text

Tipe Media

computer

Tipe Pembawa

online resource

Edisi

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Subjek

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Info Detail Spesifik

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Pernyataan Tanggungjawab

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Versi lain/terkait

Lampiran Berkas

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