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Physiographic and topographic changes in Luvuvhu River Catchment are negatively impacting on the catchment hydrology of the area. A study was carried out to extract and analyze the morphologic and hydrologic properties using GIS techniques. Digital Elevation Modeling hydro-processing procedures were used within an ArcGIS environment where Arc hydro tools were used to extract and show the spatial distribution of the properties. A hydrologically correct Digital Elevation Modeling (DEM) was generated and used to obtain primary and derived terrain elements. The results showed the automated delineation of sub-catchments and the spatial distribution of morphometric and hydrologic properties. The analysis showed how the physiographic changes were impacting on the river regimes and water resources.

Forecasting extreme hydrological events is critical for drought risk and efficient water resource management in semi-arid environments that are prone to natural hazards. This study aimed at forecasting drought conditions in a semi-arid region in north-eastern South Africa. The Standardized Precipitation Evaporation Index (SPEI) was used as a drought-quantifying parameter. Data for SPEI formulation for eight weather stations were obtained from South Africa Weather Services. Forecasting of the SPEI was achieved by using Generalized Additive Models (GAMs) at 1, 6, and 12 month timescales. Time series decomposition was done to reduce time series complexities, and variable selection was done using Lasso. Mild drought conditions were found to be more prevalent in the study area compared to other drought categories. Four models were developed to forecast drought in the Luvuvhu River Catchment (i.e., GAM, Ensemble Empirical Mode Decomposition (EEMD)-GAM, EEMD-Autoregressive Integrated Moving Average (ARIMA)-GAM, and Forecast Quantile Regression Averaging (fQRA)). At the first two timescales, fQRA forecasted the test data better than the other models, while GAMs were best at the 12 month timescale. Root Mean Square Error values of 0.0599, 0.2609, and 0.1809 were shown by fQRA and GAM at the 1, 6, and 12 month timescales, respectively. The study findings demonstrated the strength of GAMs in short- and medium-term drought forecasting.

National parks around the world have been recognised as important sources of nature experiences for both local and international visitors. In South Africa, national parks are similarly important recreational and nature tourism attractions. They offer visitors an unparalleled diversity of tourism opportunities, including game viewing, bush walks and exposure to culture and history. South African National Parks (SANParks), established in 1926, is one of the world’s leading conservation and scientific research bodies and a leading agent in maintaining the country’s indigenous natural environment. The study aims to analyse the correlation between drought and the number of tourist arrivals to the Kruger National Park (KNP). Rainfall data, as well as data on tourist arrivals at KNP for the period from 1963 to 2015 were obtained from the South African Weather Services (SAWS) and SANParks, respectively. Rainfall data were used to determine the drought years at the KNP through computing the Standardised Precipitation Index (SPI) for various stations around the park. Pearson’s correlation coefficient was used as a statistical measure of the strength of a linear relationship between drought and tourist arrivals. The results showed that KNP experienced both negative and positive tourist arrivals, although the former was the case, tourist arrivals showed an increasing trend. The correlation relationship showed that 19.36% of the drought years corresponded to a negative change in tourist arrivals to the park. The results obtained confirm that the tourism industry is a fragile industry which is prone to environmental, social and economic state of a region.

Globally, the changes exerted on the land cover have shown greater impacts on the quality and quantity of water resources and thus affecting catchment’s hydrological response (i.e., runoff, evapotranspiration, infiltration, amongst others). South Africa is a water-scarce country faced with domestic water supply challenges. A systematic review was conducted on the overview impacts of land use/land cover changes on water resources. Despite the country’s best efforts in ensuring the protection and sustainable use of water resources, the review indicated that water quality has been compromised in most parts of the country thus affecting water availability. The increase in water demand with development presents the need for better integrated strategic approaches and a change in behaviour towards water resource and land management. Thus, the review suggested a few possible solutions that will promote sustainable development, while protecting and preserving the integrity of South African water resources.