Loading...
Metal bioaccumulation, membrane integrity and chlorophyll content in the aquatic macrophyte ceratophyllum demersum from the Diep River, Western Cape
Author(s)
Erasmus, Deborah Vivian
Date Issued
2012
Type
Thesis
Publisher
Cape Peninsula University of Technology
Abstract
The Diep River is approximately 80 km in length and runs through agricultural land and
urban parts of greater Cape Town, South Africa before entering the Atlantic Ocean, via an
estuary. Generally, metal pollution in South African rivers is not well documented and
using plants to monitor metal bioaccumulation is even less documented. The aim of this
study was to investigate aluminium, iron, copper and zinc metal pollution in the Diep River
and bioaccumulation of these metals in the leaves and stems of the submerged
macrophyte Ceratophyllum demersum L. Furthermore, the effects of bioaccumulated
metals on membrane integrity and chlorophyll content of these plants were investigated.
Site 1 was situated in the upper reaches of the river adjacent to agricultural land, while site
2 was in an urban area, where industrial activities predominate. C. demersum (from an
uncontaminated source) were introduced into the river at the two sites and compared with
one another on a fortnightly basis over a 12 week period. Plants at site 2 were also
compared to existing plants that were naturally growing at the site. Comparisons were also
made between leaves and stems of the plants, to establish the organ of preference
regarding metal accumulation and storage. Samples were digested with nitric acid and an ICP-MS was used to analyse metal
concentrations in the water, sediment and plants. Chlorophyll extraction was done using
dimethyl sulphoxide (DMSO) and the absorbance values determined using a
spectrophotometer. Chlorophyll a, chlorophyll b and total chlorophyll contents were
recorded and compared. Cell membrane integrity was determined by leaving plants for 24
hours in deionised water and measuring electrical conductivity and solutes (sodium,
calcium, potassium and magnesium) before and after placement of the plants.
urban parts of greater Cape Town, South Africa before entering the Atlantic Ocean, via an
estuary. Generally, metal pollution in South African rivers is not well documented and
using plants to monitor metal bioaccumulation is even less documented. The aim of this
study was to investigate aluminium, iron, copper and zinc metal pollution in the Diep River
and bioaccumulation of these metals in the leaves and stems of the submerged
macrophyte Ceratophyllum demersum L. Furthermore, the effects of bioaccumulated
metals on membrane integrity and chlorophyll content of these plants were investigated.
Site 1 was situated in the upper reaches of the river adjacent to agricultural land, while site
2 was in an urban area, where industrial activities predominate. C. demersum (from an
uncontaminated source) were introduced into the river at the two sites and compared with
one another on a fortnightly basis over a 12 week period. Plants at site 2 were also
compared to existing plants that were naturally growing at the site. Comparisons were also
made between leaves and stems of the plants, to establish the organ of preference
regarding metal accumulation and storage. Samples were digested with nitric acid and an ICP-MS was used to analyse metal
concentrations in the water, sediment and plants. Chlorophyll extraction was done using
dimethyl sulphoxide (DMSO) and the absorbance values determined using a
spectrophotometer. Chlorophyll a, chlorophyll b and total chlorophyll contents were
recorded and compared. Cell membrane integrity was determined by leaving plants for 24
hours in deionised water and measuring electrical conductivity and solutes (sodium,
calcium, potassium and magnesium) before and after placement of the plants.
Additional information
Thesis (MTech (Horticulture))--Cape Peninsula University of Technology, 2012.
File(s)![Thumbnail Image]()
Loading...
Name
187001510_Erasmus_DV_Mtech_Horticulture_Appsc_2012_20121840.pdf
Description
Thesis
Size
66.65 MB
Format
Adobe PDF
Checksum
(MD5):2c84151be6674cc31717932cc6a1f822