Prof. Kevin Balkwill – SAAB Silver medal winner 2024
Abstract:
Zeroing in on the troublesome taxonomy of Xerophyta in South Africa
Kevin Balkwill, Shane Burns and Douglas McMurtry
Xerophyta (Velloziaceae) is an African genus of poikilochlorophyllous resurrection plants. I first troubled over this group in 1983, because I could not identify a specimen collected on Abel Erasmus Pass. Most species grow on rock outcrops or in very shallow soil, where there is little competition and low fuel loads. This habitat occurs as isolated patches, reducing geneflow and facilitating speciation. A revision of the African species was undertaken in 2013 and 15 species, one with two varieties, were recognized for South Africa, but the authors predicted that “yet more species will be described in the future”. Three groups are identifiable in South Africa: shrubby; herbaceous; and a single species that was previously recognized as the genus Talbotia. Our methods include fieldwork, cultivation, herbarium work and anatomical investigations. I will discuss the characters we find useful to distinguish species, the challenges with which we wrestle and briefly indicate how our findings fulfill the prediction that there are many more species to describe.
Prof. Stefan Siebert – SAAB Silver medal winner 2024
We apologize for the unstable internet connection during the recording of the live webinar. Unfortunately there is a three minute silence in the talk due to lost signal.
Abstract:
Rooted in the Earth: Understanding plant-soil dynamics of ‘harsh soil’ environments in South Africa
By Stefan Siebert, Unit for Environmental Sciences and Management, North-West University, Potchefstroom
Geological substrates that give rise to ‘harsh’ soils, have long fascinated botanists due to the specialised edaphic floras they support. Harsh soils are characterised by essential element deficiencies, extreme high or low pH, high levels of potentially toxic elements, shallow depth with poor structure or texture, and bare or open habitats with high evapotranspiration. Such soils naturally pose significant challenges for plant survival and growth. Ecosystems of harsh soils serve as model habitats for interdisciplinary research, offering insights into how diversity is generated and maintained, and providing a basis for exploring conservation and restoration practices. They also offer an excellent platform for training and mentoring young scientists in various aspects of plant sciences. Research on the ecology of harsh soils has evolved globally, making it increasingly important to highlight key areas of study, identify information gaps, and outline future directions, especially in southern Africa. There is an urgent need to build local capacity to develop a knowledge base around our rich diversity of edaphic specialists, which can be leveraged to find ecosystem solutions for phytomining and phytoremediation technologies in restoration ecology.
Dr. Hannah Butler – SAAB Bronze medal winner 2024
Abstract:
Expanding on the pollination syndrome concept: case studies from the South African Amaryllidaceae
It has long been accepted that flowers are shaped by their pollinators. Size, shape, colour, scent etc are all traits that can all be selected for by a particular pollinator. This has led to the widespread acceptance of ‘pollination syndromes’, or where a certain suite of traits is associated with a certain pollinator. However, while some research supports this, others do not. My own research on South African Amaryllidaceae, a charismatic and beautiful plant family, has shown that sometimes what is expected is not always what is found, and that floral traits can still be associated with a pollinator despite not fitting neatly into its expected pollination syndrome. In this talk, I draw upon my own research from my PhD and now post-doc position to show how the diversity of Amaryllidaceae in South Africa has evolved to fit different pollinators.
Prof. Brian van Wilgen
Abstract:
Designing research for impact: the case of invasive Prosopis trees in eastern Africa
Centre for Invasion Biology, Stellenbosch University, South Africa
In 1982, the SCOPE program on the ecology of biological invasions challenged the
global research community to use scientific knowledge to develop effective ways to manage biological invasions. Much has been learnt in the intervening four decades, and yet there are few examples of truly trans-disciplinary studies that are deliberately designed to integrate research across many fields of study, as well as to involve potential end-users at all stages of the research. Such integrated studies could potentially significantly enhance the likelihood of effective implementation. This talk is about one such study (the “Woody Weeds” project), in which the ecology and management of invasive alien Prosopis trees in eastern Africa has been examined over the past seven years. Prosopis trees were introduced to Africa from the Americas to provide a suite of benefits. However, they subsequently became invasive, resulting in detrimental impacts on ecosystems and people’s livelihoods. The management of Prosopis trees is complex, with no apparent simple solutions being available. Finding solutions will require integrated multi-disciplinary research approaches involving ecologists, economists, and social scientists, as well as close collaboration with the potential end-users of research findings. This talk addresses the history of introduction and spread of Prosopis trees, and how attitudes towards the species changed and diverged over time, leading to conflict. It discusses how field data were collected from the same sites, and at the same scale, across disciplines so that direct comparisons could be more easily integrated and up-scaled. It also
discusses how policy-makers and potential end-users were involved at all stages of the project, and how their input helped to shape research questions. Finally, I address how this information will help to deal with this significant environmental problem.