SciELO - Scientific Electronic Library Online

 
vol.37 número3Changing hydroclimatic and discharge patterns in the northern Limpopo Basin, ZimbabweEcological impacts of small dams on South African rivers Part 2: biotic response - abundance and composition of macroinvertebrate communities índice de autoresíndice de assuntospesquisa de artigos
Home Pagelista alfabética de periódicos  

Serviços Personalizados

Artigo

Indicadores

Links relacionados

  • Em processo de indexaçãoCitado por Google
  • Em processo de indexaçãoSimilares em Google

Compartilhar


Water SA

versão On-line ISSN 1816-7950
versão impressa ISSN 0378-4738

Resumo

MMUALEFE, Lesego C  e  TORTO, Nelson. Water quality in the Okavango Delta. Water SA [online]. 2011, vol.37, n.3, pp.411-418. ISSN 1816-7950.

The Okavango Delta ecosystem sustains a large number of plant and animal species as well as providing resources for the livelihood of the riparian human population. Despite changes in flow patterns, rainfall and other climatic conditions over the past decades, the system has responded well to maintain low salt-water balances through evapotranspiration and chemical precipitation processes. The electrical conductivity and total dissolved solids are generally low, with values less than 200 µS·cm-1 and averaging 40 mg·ℓ-1, respectively. The dissolved oxygen and dissolved organic carbon range from 1.8 to 8.8 and 5 to 15 mg·ℓ-1, respectively, while pH ranges from 6.7 to 10.3. Total nitrogen and phosphorus are generally low with maximum concentrations of 1.7 and 1.6 mg·ℓ-1, respectively, recorded downstream of the Delta. Even though most of these quality parameters are within limits for potable water, the Delta's ecosystem needs to be protected from anthropogenic activities. Past use of persistent organic pollutants requires monitoring of impacts of their residues on the plants and animal species within the ecosystem, in order to maintain its rich biodiversity. This review focuses on chemical quality data for water and sediments in the Okavango Delta published between 2000 and 2010. Despite the shortage of published data, it is hoped that this review will provide an overall picture of the status quo of the Delta's water and will set the direction for future monitoring efforts.

Palavras-chave : Okavango Delta; water quality; pollution; metals; pesticides.

        · texto em Inglês     · Inglês ( pdf )

 

Creative Commons License Todo o conteúdo deste periódico, exceto onde está identificado, está licenciado sob uma Licença Creative Commons