Young minds look at old data

SAEON Fynbos Technical Officer Abri de Buys (centre) shows how the monitoring instrumentation records data in the field. With him are Thebogo Madlala, Sibongile Manamathela and Priscilla Kjizi. (Photo:Ruan Cowan) Sibongile Manamathela measures height of water flow over the V notch weir to confirm calibration of the water level instrumentation. (Photo:Ruan Cowan) University of the Western Cape Water Studies Honours students taking on hydrology projects with the SAEON Fynbos Node. From left: Sibongile Manamathela, Thebogo Madlala, Ruan Cowan, Priscilla Kjizi, Mamane Moeketsane and Matthew Damons. (Photo: Nicky Allsopp) View larger version

The SAEON Fynbos Node is collaborating with six Honours students from the University of the Western Cape on projects to develop their hydrological skills.

The students, under the supervision of Professor Dominic Mazvimavi at the Institute of Water Studies in the Department of Earth Sciences, are exploring a variety of questions associated with the long term experimental catchment monitoring at Jonkershoek and Jakkalsrivier. Four of the students will be using data from the Jonkershoek and Jakkalsrivier catchment experiments and two will be doing field based studies.

Data from the 1930s onwards …

The CSIR has recently transferred custodianship to SAEON of the data from the experimental catchment monitoring programmes which were run in places like Jonkershoek, Jakkalsrivier and Cathedral Peak. Some of this data, such as that from Jonkershoek, stretches back to the 1930s and consists for several million records.

The experimental catchment monitoring programmes were set up to answer questions about how much water alien plantation species such as pines may use compared to natural vegetation. The evidence came out in favour of maintaining indigenous vegetation in catchments to secure the long-term sustainability of water delivery.

Other evidence was used to determine the best fire cycles and season of burn in fynbos and grasslands for securing water delivery of high quality.

Answering new questions

However, data of this length continues to supply opportunities for answering new questions. In this day and age questions around the impacts of global change on the hydrology and ecology are particularly coming to the fore.

The students will be studying specific details of flood and low flow regimes, comparing between catchments and sites and asking questions such as have the catchments maintained similar responses to rainfall over time. One project will specifically look at temporal and spatial variation of rainfall in Jonkershoek, while another will look at potential changes in evapotranspiration. These projects can potentially refine hydrological models of impacts of global change on water delivery.

Two of the students will be engaged in more hands-on research and will be accompanying Node Technical Officer, Abri de Buys, on his regular monitoring rounds. One student will investigate the accuracy of rating equations in estimating flow rates and another will be examining the quality of water in the upper reaches of the Eersterivier.

Managing large data sets

Victoria Goodall, Node Data Scientist, will be helping the students get to grips with managing extremely large data sets, many with data recorded at hourly time intervals over several decades, as well as provide input on statistical approaches.

The Applied Center for Climate and Earth Systems Science (ACCESS) is acknowledged for funding for bursaries for four of the students.