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Prediction and ecotoxicological effects of runoff induced pesticide contamination in agricultural surface waters : a risk assessment using GIS and microcosms

Dabrowski, James Michael (Stellenbosch : Stellenbosch University, 2001-12)

ENGLISH ABSTRACT: Runoff is generally regarded as one of the most important routes of nonpoint source pesticide pollution in agricultural surface waters. Of major concern is the fact that low, sub-lethal levels of pesticide ...

The influence of different management practices on soil faunal activity in vineyard soils

Albertus, Randal Marius Colin (Stellenbosch : Stellenbosch University, 2002-12)

ENGLISH ABSTRACT: Food demands for the ever-increasing human population is increasing the pressure on the agricultural sector to produce more food. In order to satisfy these demands, farmers are turning to chemical ...

The ability of terrestrial Oligochaeta to survive in ultramafic soils and the assessment of toxicity at different levels of organisation

Maleri, Rudolf A. (Stellenbosch : University of Stellenbosch, 2006-12)

Metals are natural elements of the earth crust usually present at low concentrations in all soils. Although many metals such as cobalt, copper, iron and zinc are essential to living organisms, at elevated concentrations ...

Cellular responses to Cd, Pb and Zn in shrews (Myosorex varius and Crocidura flavescens) and BALB/c mice

Chapman, Aletia Ann (Stellenbosch : Stellenbosch University, 2000-12)

ENGLISH ABSTRACT: Shrews are excellent bioindicators of environmental heavy metal pollution. This is due to their diets and the high rate of consumption at which these small mammals consume their prey. Shrews feed mostly ...

Evaluation of the suitability of responses on various organisational levels in terrestrial Oligochaeta to determine species sensitivity relationships

Fourie, Frana (Stellenbosch : Stellenbosch University, 2011-03)

ENGLISH ABSTRACT: Species differ in their sensitivities to toxicants and these differences are exploited in ecological risk assessment methods such as species sensitivity distributions (SSDs). The most commonly used endpoints ...

Cellular stress responses to cadmium contamination as measure of sensitivity in intertidal molluscan species

Schoeman, Werner (Stellenbosch : University of Stellenbosch, 2007-03)

The ability of various molluscan species to accumulate toxicants such as cadmium from natural waters in quantities that are many orders of magnitude higher than background levels are well-known. This phenomenon ...

Contamination levels in and cellular responses of intertidal invertebrates as biomarkers of toxic stress caused by heavy metal contamination in False Bay

Mdzeke, Naomi Patience (Stellenbosch : Stellenbosch University, 2004-03)

ENGLISH ABSTRACT:Heavy metals are persistent environmental contaminants whose sources of inputs into the environment are both natural and anthropogenic. The levels of heavy metals (cadmium, copper, nickel, lead and zinc) ...

Ecotoxicity and environmental fate of diesel and diesel blends produced by Sasol’s Fischer-Tropsch processes using natural gas and coal as feedstock as well as biodiesel and biodiesel blends

Albertus, Randal Marius Colin (Stellenbosch : Stellenbosch University, 2012-12)

ENGLISH ABSTRACT: World crude oil demand and production is set to increase in the long term and is projected to increase from 82 barrels per day in 2007 to an estimated 104 million barrels per day in 2030 according to the ...

Die ultrastruktuur van sperme van die rooibok Aepyceros melampus (Lichtenstein, 1812) in die Nasionale Krugerwildtuin met spesiale verwysing na die invloed van koperbesoedeling

Ackerman, Dirk J. (Dirk Jacobus) (Stellenbosch : Stellenbosch University, 1995-08)

ENGLISH ABSTRACT: Graling in the Kruger National Park. south of Phalaborwa Gate, is contaminated with copper, probably from a nearby copper refinery. Cattle in the neighbourhood have died from copper poisoning while the ...

Influence of clay content and salinity on the bioavailability and toxicity of metals (copper and zinc) to soil organisms

Owojori, Olugbenga J. (Olugbenga John) (Stellenbosch : University of Stellenbosch, 2009-12)

ENGLISH ABSTRACT: Metal pollution is a problem of increasing global concern. It could arise from industrial activities, as well as pesticide use in agriculture, among other sources. For adequate protection of the soil ...