Prof Theodorus Wassenaar

Research interest:

In the broadest sense I am interested in sustainable land management and biodiversity conservation, with a focus on land and ecosystem degradation and the contribution that ecological restoration can make to the protection of biodiversity and the support of livelihoods. Although my earlier work was done in sub-tropical dune forests, I am particularly interested in arid environments such as the Namib Desert and the arid savannas that make up most of Namibia and the southwestern part of the African continent.

I support the notion that science has to have some meaning for society. As a result, my research interests fit into many aspects of sustainable land management, including improving the efficiency of the mitigation hierarchy in an effort to decrease environmental impacts and more focused work on factors that affect the success of ecological restoration. My work is therefore mainly in applied fields of ecology, but I am also interested in closely related but more purely scientific topics such as plant physiological stress responses to water deficits and organism-water-environment relations. With climate, and particularly the climatic factors that determine spatial-temporal moisture patterns being such an important driver of ecological dynamics in arid environments, I am also interested in climatic features such as fog and its role in shaping biological diversity patterns and ecosystem response to disturbance. Findings from such projects allow a clearer description of the biological context within which impacts can be mitigated, and an improved ability to predict when they can not. In addition to my scientific work, I am also keenly interested in using different educational and training approaches to inform and capacitate people as custodians of our natural environment.

Key publications:

Cunningham, P., Wassenaar, T. & Henschel, J. (2012) Notes on some aspects of the ecology of the Husab sand lizard, Pedioplanis husabensis, from Namibia. African Herp News 56, 1-11.

Grainger, M.J., van Aarde, R.J. & Wassenaar, T.D. (2011) Landscape composition influences the restoration of subtropical coastal dune forest. Restoration Ecology, 19, 111–120. doi:10.1111/j.1526-100X.2009.00630.x 

Helmschrot, J. et al. (including Wassenaar, T.D.) (2014) SASSCAL WeatherNet to support regional weather monitoring and climate-related research in Southern Africa. Hydrological Sciences and Water Security: Past, Present and Future (Proceedings of the 11th Kovacs Colloquium, Paris, France, June 2014). 

Henschel, J.R., Wassenaar, T.D., Kanandjembo, A., Kilbourn Louw, M., Neef, G. Shuuya, T., Soderberg, K. (2018) Roots point to water sources of Welwitschia mirabilis in 1 a hyperarid desert. Ecohydrology. https://doi.org/10.1002/eco.2039

Kaseke, K. F., Tian, C., Wang, L., Seely, M., Vogt, R., Wassenaar, T., Mushi, R. (2018) Fog spatial distributions over the central Namib desert - an isotope approach. Aerosol and Air Quality Research 18, 49–61. 201 DOI: 10.4209/aaqr.2017.01.0062

Kirchhof, S., Hetem, R.S., Lease, H.M., Miles, D. Mitchell, D. Müller, J., Rödel, M-O., Sinervo, B., Wassenaar, T. & Murray, I.W. (2017) Thermoregulatory behavior and high thermal preference buffer impact of climate change in a Namib Desert lizard. Ecosphere, 8(12):e02033, 10.1002/ecs2.2033.

Redi, B.H., van Aarde, R.J. & Wassenaar, T.D. (2005) Coastal dune forest development and the regeneration of millipede communities. Restoration Ecology 13, 284-291.

Seely, M.K., Ward, V. & Wassenaar, T.D. (2014) Science education for sustainable development: the Gobabeb experience. Transactions of the Royal Society of Southern Africa. DOI: 10.1080/0035919X.2014.949903.

Kummssa, D.B., van Aarde, R.J. & Wassenaar, T.D. (2004) The regeneration of soil micro-arthropod assemblages in a rehabilitating coastal dune forest at Richards Bay, South Africa. African Journal of Ecology 42, 346-354.

van Aarde R.J., Ferreira S.M., Kritzinger J.J., Van Dyk P.J., Vogt M. & Wassenaar T.D. (1996) An evaluation of habitat rehabilitation on coastal dune forests in northern KwaZulu-Natal, South Africa. Restoration Ecology 4, 334-345.

van Aarde R.J., Ferreira S.M., Wassenaar T.D. & Erasmus D.G. (1996) With the cats away the mice may play. South African Journal of Science 92, 357-358.

van Aarde R.J., Ferreira S.M. & Wassenaar T.D. (2004) Do feral house mice have an impact on invertebrate communities on sub-Antarctic Marion Island? Austral Ecology 29, 215–224.

Vogt, R., Gottlieb, R., Wassenaar, T. & Seely, M.K. (2016) FogNet – Observing fog in the central Namib. Proceedings: 7th International Conference on Fog, Fog Collection and Dew. 195.

Wassenaar, T.D., Ferreira, S.M. & van Aarde, R.J. (2007) Flagging aberrant sites and assemblages in restoration projects. Restoration Ecology 15, 68-76.

Wassenaar, T.D., Henschel, J.R., Pfaffenthaler, M.M., Mutota, E.P., Seely, M.K. & Pallet, J. (2013) Ensuring the future of the Namib’s biodiversity: ecological restoration as a key management response to a mining boom. Journal of Arid Environments 93, 126-135.

Wassenaar, T.D. & van Aarde, R.J. (2001) Short term responses of rehabilitating coastal dune forest ground vegetation to livestock grazing. African Journal of Ecology 39, 329 339.

Wassenaar, T.D. & van Aarde, R.J. (2003) Evaluating restoration success – post-mining coastal dune forest regeneration in South Africa. Proceedings of the Mining and Sustainable Development Conference, November 2003, Sandton, South Africa. Chamber of Mines of South Africa. Obtainable at www.bullion.org.za

Wassenaar, T.D., van Aarde, R.J., Pimm, S.L. & Ferreira, S.M. (2005) Community convergence in disturbed sub-tropical dune forests. Ecology 86, 655-666.

Wassenaar, T.D. & Yates, M. (2008) Is it mineral? Is it vegetable? Perceptions about ecological rehabilitation in the Namibian mining industry. Proceedings of the Third International Seminar on Mine Closure. 14-17 October, Johannesburg, South Africa.