Exploring the potential of using remote sensing data to model agricultural systems in data-limited areas

This research explores the potential of combining remote sensing data with crop models in data-limited areas. This because the use of crop models, particularly in remote and rural areas, is often limited by the lack of reliable field input data. As such, increasing efforts are being made globally to assimilate remotely sensed data into crop models to improve their overall performance and use. Nevertheless, very few such studies have been conducted in South Africa. Therefore, this study assesses how well the model assimilated with remotely sensed data compares with a crop model calibrated with actual ground data. With an intention to improve the capacity and use of crop models in data-limited areas.

Student: Luleka Dlamini

Supervisor: Olivier Crespo

An investigation of the impacts of intra-seasonal rainfall variability on the maize growing season of Limpopo Province, South Africa

This thesis investigates how changes in intra-seasonal rainfall characteristics such as onset, cessation and duration impact maize growth and yield in Limpopo Province from 1990-2014. The approach of this study identifies and distinguishes synoptic states associated with rainfall characteristics that are suitable for growing maize from those that are not suitable using Self-Organising Maps.

Student: Ntanganedzeni Ramugondo

Supervisors: Olivier Crespo and Izidine Pinto

Assessing the climatic suitability of underutilized crops to future climatic projections using Ecocrop model: A case of Bambara groundnut in Southern Mali

This research assesses the climatic suitability of Bambara groundnut, an underutilized crop to changes in future climate projections.  As the climate changes, the suitable areas for the cultivation of crops change. Over southern Mali, several studies have indicated a reduction in areas suitable for the cultivation of crops, especially staple crops, due to the changes in future climatic projections. However, few studies have been conducted on the suitability of the underutilized crops. Thus, this study assesses how the changes in future climatic projections will impact the future climatic suitability of the crop in Southern Mali. This research aims to contribute to the ongoing debate on underutilized crops serving as an adaption option to climate change and their potentials in helping improve the food system.

Student: Ezinwanne Ezekannagha

Supervisors: Olivier Crespo

Determining the percentage of legal clearing of indigenous vegetation for agricultural practices within the Sandveld region, and examining whether the EIA process could be improved to promote an increase in legal clearing of indigenous vegetation

This study will focus on an area known as the Sandveld, situated along the west coast of South Africa. This area is an extensive area filled with a great array of indigenous vegetation within the boundaries of Western Cape. The Sandveld forms part of a biodiversity hotspot, World Heritage Site and one of the six ‘Floral Kingdoms’ in the biosphere (Capenature, n.d.). The indigenous plant species in the Sandveld is of great ecological importance and on the verge of becoming extinct. The indigenous plants species in the Sandveld, are the most threatened plant species of all the areas within the GCBC. Given the above-mentioned, the biodiversity-loss in the area is occurring at an alarming rate.

With species sizes so small and found nowhere else in the biosphere, it raises an alarming need for conservation. Cultivating a field or clearing an area to build a single house, could destroy the entire global population of this unique species (Conservation South Africa, 2017). This is how rare these plant species are. Currently, various spheres of government are attempting to conserve the Sandveld; but the loss of indigenous vegetation in the area is continuing at a concerning rate. Large portions of fynbos are currently being lost due to illegal clearing of indigenous vegetation for agricultural purposes. The threat of habitat loss is concerning, as 50 percent of fynbos have already been ploughed for agricultural purposes such as potatoes and rooibos (Low et al, 2004). Due to recent drought conditions, resultant of global climate change; many farmers have been illegally clearing natural land to expand on rooibos farming. Less than 50 percent of the Sandveld remain untransformed and the rapid rooibos industry expansion is continuously placing burden on biodiversity; with an average of 2,7 hectare being cleared illegally daily (Conservation South Africa, 2017).

South Africa has extensive environmental legislation in aid of protecting the natural resources of the country. However, illegal clearing of indigenous vegetation is still taking place within the Sandveld. This study will focus on the effectiveness of the Environmental Impact Assessment Process (EIA process), as a protective measure for indigenous plant species within the Sandveld. The EIA process helps identify possible negative environmental impacts on the environment for a proposed development. This process takes place before to the commencement of a development and aims to find mitigation measures to the negative impacts.

Student: Grant Dyers

Supervisors: Peter Johnston

Modelling the historical and future impacts of climate change on maize and soybean yields in Central and Eastern provinces of Zambia

This research assesses the likely impacts of climate change on the yields of maize and soybean in Zambia. While similar studies have been done on the subject, few studies have used locally downscaled data specifically for Zambia. Moreover, since climate change impacts are regional specific and need to be managed as such, this study aims at assesing how maize and soybean yields responds climate change using locally downscaled climate data from general circulation models. Understanding the impacts of climate change in a local area is beneficial for developing strategies that may be useful for developing climate smart management strategies to ensure sustainability of household and national food security in the country.

Student: Alice Chilambwe

Supervisors:Olivier Crespo