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Eight medium amendments were conducted on top of a fine ash coal dump (i) to evaluate a few cost‐effective treatments that could determine the minimum fertility status required for the local ash to support the establishment of a viable vegetation cover, and (ii) to select suitable grass species that would establish on the ash and could serve as a foundation for long‐term rehabilitation. Degree and success of grass establishment per medium amelioration treatment is expressed in terms of total biomass, percentage basal cover, and in terms of a condition assessment model. Both the chemical and physical nature of the ash medium before and after amendment was characterized, as were the concentrations of some essential and potentially toxic elements in leaf samples. In terms of medium amelioration 5000 kg ha−1 compost, or 500 kg ha−1 kraal manure or 480 kg 2:3:2 ha−1 proved to be most effective. The grass species that occurred with the highest frequency, irrespective of treatment, were the perennials bermudagrass [Cynodon dactylon (L.) Pers. var. dactylon], weeping lovegrass [Eragrostis curvula (Schrader) Nees], and the annual teff [Eragrostis tef (Zuccagni) Trotter]. Of the potentially toxic extractable metals monitored in the leaves of vegetation on the dump, only Se accumulated to an average level of 4.4 mg kg−1 that could be toxic to livestock.

This paper describes a collaborative process of identifying and prioritising current and future water research questions from a wide range of water specialists within South Africa. Over 1 600 questions were collected, reduced in number and prioritised by specialists working in water research and practice. A total of 59 questions were finally proposed as an outcome of the study and are categorised under the themes of change, data, ecosystems, governance, innovation and resources. The questions range in scale, challenge and urgency, and are also aligned with prevailing paradigms in water research. The majority of the questions dealt with relatively short-to medium-term research requirements and most focused on immediate issues such as water supply, service delivery and technical solutions. Formulations of long-term research questions were sparse, partly because some of the principles and methods used in this study were difficult to apply in the South African context, and also because researchers are influenced by addressing what are believed to be the more immediate, short-term water-related challenges in South Africa. This is the first initiative of its kind to produce a comprehensive and inclusive list of research priorities for water in South Africa.

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