Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Titre : Investigation of the drivers for water quality decline and risks thereof to agricultural activities in the Breede River catchment

Auteur : Van Tonder, D.M. 

Université de soutenance : North-West University

Grade : MSc (Environmental Management) 2022

Résumé partiel
Agriculture in the Breede River catchment contributes significantly to international exports and the economy of the Western Cape Province. The success of the agricultural sector in the Breede River catchment is an important driver for the expansion of urban and peri-urban areas. However, the expansion of the urban peri-urban footprint and intensified agricultural activities, such as water abstraction for irrigation and the return flows entering rivers, are linked to a decline in water quality in the catchment. Previous studies have shown that water quality in the Breede River catchment has been declining with some potential drivers identified as the rapid urbanisation, limited financial resources and technical capabilities available for the maintenance and upgrade of the capacity waste water treatment works. Although the risks posed to the agricultural industry in the Breede River catchment have been acknowledged, the nature and extent thereof were unclear. The research study was aimed at investigating the key drivers and risks associated with the decline in water quality to the agricultural sector in the Breede River catchment. Subsequently, three Research Objectives were set : (1) to re-evaluate the water quality in the Breede River catchment ; (2) to identify the key drivers of the decline in water quality of the agricultural sector in the Breede River catchment ; and (3) to identify and evaluate the risks posed by the declining water quality in the Breede River catchment to agricultural activities. In order to meet these objectives, a review of the literature pertaining to water quality and the impact thereof on agriculture, in line with the research title, problem and objectives was conducted. Additionally, an empirical investigation utilising a mixed methods research approach was followed whereby qualitative and quantitative data was collected. The long-term water quality of the Breede River was evaluated through time series, Piper and Gibbs diagram as well as the calculation of the Water Quality Index and comparison of the water quality with national standards in order to evaluate the suitability of the surface water for agricultural activities in the Breede River catchment. In addition a total of 28 participated (farmers and environmental experts) in face to face or online interviews and the completion of questionnaires with both open and close-ended questions. Both the qualitative and quantitative data from the questionnaires were captured for analysis and a thematic analysis, using accepted data coding methods, was conducted.

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