In highly variable water regimes of semi-arid savannahs, water is the key driving force for biotic and abiotic processes. Understanding and measuring components of the hydrological cycle at landscape scale is however difficult because of the spatiotemporal variation of these processes. Hydropedology is a new interdisciplinary research field aiming to use soil information to conceptualise hydrological processes at different scales. In this study, a hydropedological approach was used to identify key hydrological flowpaths on a granitic catena in the Stevenson–Hamilton Supersite in the Kruger National Park. Soils from 49 plots, spaced 10 m apart along a catena, were classified, and their morphology was interpreted in relation to the dominant hydrological response. Soil samples were taken at 10-cm-depth intervals for chemical and physical analysis to assess the relationship between their expected hydrological behaviour and physiochemical properties. The hydropedological survey indicated that the crest is dominated by freely drained recharge soils where infiltration and vertical drainage are dominant. On the midslope, the underlying bedrock has restricted permeability; this promotes lateral flow at the soil/bedrock interface. On the upper footslope, high clay content soils (sodic) restricts further lateral drainage, resulting in return flow (seepage). Overland flow is dominant on the upper and lower footslope. The valley bottom is occupied by freely drained alluvial soils, which act as a recharge zone. The chemical and physical analyses of soil support the interpretations of the hydropedological interpretation of the soil morphology. Conservation implications: Understanding hydrological processes is important for sustainable water resource management, especially in the areas with highly variable water regimes. A hydropedological approach provides an efficient method to characterise dominant flowpaths at landscape scale. This aids the estimation of the hydrological sensitivity of the landscape to climate and land use changes.

Urbanization and hydrology have an interactive relationship, as urbanization changing the hydrology of a system and the hydrology commonly causing structural damage to the infrastructure. Hydrological modelling has been used to quantify the water causing structural impacts, and to provide solutions to the issues. However, in already-urbanized areas, creating a soil map to use as input in the modelling process is difficult, as observation positions are limited and visuals of the natural vegetation which indicate soil distribution are unnatural. This project used historical satellite images in combination with terrain parameters and digital soil mapping methods to produce an accurate (Kappa statistic = 0.81) hydropedology soil map for the Cosmo City suburb in Johannesburg, South Africa. The map was used as input into the HYDRUS 2D and SWAT hydrological models to quantify the water creating road damage at Kampala Crescent, a road within Cosmo City (using HYDRUS 2D), as well as the impact of urbanization on the hydrology of the area (using SWAT). HYDRUS 2D modelling showed that a subsurface drain installed at Kampala Crescent would need a carrying capacity of 0.3 m3·h−1·m−1 to alleviate the road damage, while SWAT modelling shows that surface runoff in Cosmo City will commence with as little rainfall as 2 mm·month−1. This project showcases the value of multidisciplinary work. The remote sensing was invaluable to the mapping, which informed the hydrological modelling and subsequently provided answers to the engineers, who could then mitigate the hydrology-related issues within Cosmo City.

Local environmental gradients on a catenal scale create ecological patterns from the crest to the stream of the hillslope. Bottom-up drivers interact with top-down controls to give rise to these patterns. A multidisciplinary project was conducted to study the processes that govern functioning, structure and heterogeneity on a catena in a third-order catchment in the Southern Granite Supersite in the Kruger National Park. The project included abiotic components (e.g. groundwater-surface water interactions, soil chemical and physical properties) as well as biotic components (e.g. soil microbes, small aquatic organisms in ephemeral pools, plant communities, vegetation structure and mammal diversity). Each of these components was investigated in detail along the catenal gradient and reported on in separate articles in this special issue. The drought of 2015–2016 occurred during the sampling period of the study and information on the response of vegetation and mammals to the drought were included. In this article, a synthesis of findings from the separate components or disciplines is provided to highlight the interactive functioning and ecological patterns of the catena. These findings were then used to develop a framework for multidisciplinary studies in similar environments. The framework highlights the interactive relationships between various components of the ecosystem and the importance of a multidisciplinary approach. Conservation implications: The findings of this study were used to develop a conceptual framework outlining how a range of biotic and abiotic patterns and processes interact along the catenal gradient. The framework highlights the importance of recognising these interactions in a multidisciplinary approach focused on one supersite.

The science of hydropedology has progressed significantly in the past two decades, especially with regards to the interpretation of soil morphology and relating these interpretations to the hydrological behaviour of horizons, profiles, hillslopes and catchments. Soil classification is pivotal to hydropedological interpretation and several studies have attempted to relate soil forms (as in the South African soil classification) to hydropedological behaviour. Here we present a cohesive grouping of the soil forms into four main hydropedological types, namely recharge, interflow, responsive and stagnating soils. This grouping will improve the efficiency of hydropedological assessments of soils, hillslopes and catchments for hydrological and ecological purposes.

Recently published results regarding South Africa’s cropping potential show that about one third of the arable land is of low potential, located mainly in semi-arid areas, with the main problem being water shortage. This is therefore an appropriate time to review priorities and procedures, for selecting benchmark ecotopes to represent marginal areas, and for research needs with regard to water conservation strategies to mitigate the problems of low yields. Relevant international principles encapsulated in the words agro-ecology, sustainability and socio-economic conditions, are discussed. Relevant new technologies are described, namely: digital soil mapping that will facilitate the identification of benchmark ecotopes; a stochastic procedure to predict rainfall intensity data from daily rainfall that will facilitate runoff predictions; a crop yield cumulative probability procedure that enables sustainability to be described quantitatively. As a case study, results from a successful field experiment using the infield rainwater harvesting production technique on benchmark ecotopes in a semi-arid area, inhabited by subsistence farmers, are presented. The objectives of the study, procedures used and the method of expressing the results are recommended as guidelines for contributing towards mitigating the problem of low crop productivity across a large portion of the arable area in South Africa.

Savannas make up about 20% of the global land-surface and are dependent on fires to maintain a balanced ecosystem. Fires in other fire-driven landscapes, particularly wildfires, were found to have negative effects on various soil properties. However, there is a lack of studies confirming the effect of fires on soil hydrology in African savanna soils. A long-term fire experiment in a South African savanna provided an opportunity to investigate the effect of different prescribed fire frequencies on soil properties in situ across coarse-grained granitic and fine-textured basalt-derived soils. Soil properties were compared between soils exposed to annual fires, fires every 2-4 years and where fires have been excluded for approximately 60 years. Across all three fire treatments, unsaturated hydraulic conductivity (K-unsat) was measured using a Tension Disc Infiltrometer to infer infiltration rates, saturated hydraulic conductivity (K-sat) measured with a Guelph Permeameter, soil water potential calculated using a Decagon WP4-T Dewpoint Potentiometer to infer soil water retention and soil total C and N measured using a LECO CNS TruMac Series Analyser. Our study found that K-unsat is not affected by frequent annual fires which have infiltration rates similar to soils where fires have been excluded for nearly 6 decades. However, recently burnt granitic soils, i.e. three months prior, have significantly slower K-unsat which were as low as < 1 mm hr(-1) compared to a mean K-unsat of 30 mm hr(-1) on annually burnt soils, alluding to short term fire impacts on soil infiltration. Hence, we believe that time following a fire plays a greater role on K-unsat than fire frequency. Fires did not affect K-sat within the initial 2-5 cm of the soil surface. In general, the granitic soils had faster K-unsat and K-sat than the basaltic soils. Soil water potential, total C and N was significantly greater in the fire exclusion sites over both parent materials. Soil water and nutrient availability is critical in a post-fire environment to facilitate vegetation recovery in African savannas. These systems are resilient to fires which do not have long-term negative impacts on soil hydrology and nutrients, but instead increases the spatio-temporal variation in soil properties necessary in maintaining savanna heterogeneity.

Urban sprawl and the accompanying development is set to increase pressure on the hydrological system. In turn, the hydrology of an area affects the infrastructure. Hydropedology, can assist to sustainably manage the infrastructure-hydrology interaction. Even though the hillslope scale is accepted as ideal for hydropedological assessments, regional soil maps have been used when hydropedology assessments were undertaken for larger areas. This study uses a hillslope based approach within a digital soil mapping method to conduct a hydropedological assessment for a large (12,000 ha) urban area under developmental pressure within Johannesburg, South Africa. One hundred and thirty-three hillslopes within the study area were delineated and mean and standard deviation of terrain attributes were calculated for each hillslope. Based on these values, the conditioned Latin hypercube sampling (cLHS) method was used to select 30 hillslopes on which soil observations would be made, in a transect, at the surveyor's discretion. A hydropedological soil map was created with the multinomial logistic regression algorithm and the 142 soil observations made. The soil map attained an acceptable 69% validation point accuracy and a Kappa value of 0.59, and was used to create a hillslope conceptual hydrological response map. The chi-square test and QQ-plots indicated that the cLHS selected hillslopes represented the hillslopes of the study site well, but the observations only represented some of the terrain attributes well. Despite the range of the observation dataset covering at least 98.7% of the pixels for the multi resolution index of valley bottom flatness (MRVBF), topographic wetness index (TWI) and altitude above channel network layers, their site distribution differed statistically from that of the observation distribution. The hillslope based survey approach allowed for an acceptable soil map to be created, while allowing for hillslope based hydropedological interpretations to be made. The "cost" for the hillslope based approach was that the distribution of some covariates for the observations differed from their distributions over the entire site.

From a natural underground cavity and two locations situated in a well, three CO2 injections have been designed and performed under controlled conditions in order to study its migration along the carbonate vadose zone and to test geochemical and geophysical techniques. After the understanding of the natural CO2 dynamics and the establishment of a baseline, some numerical simulations have been performed to help to optimize the monitoring strategy (spatially and temporally). A mixture of CO2 + noble gases has been injected and the results show that CO2 subsurface leakage can be anticipated thanks to these inert chemical gases used as tracers (He + Kr). The geochemical and geophysical monitoring approaches are very complementary.

Methods developed to determine the amount of water required (EWR) to sustain ecosystem services in non-perennial rivers need a different approach to those used in perennial rivers.Current EWR methods were mostly developed for use in perennial rivers.Non-perennial rivers differ from perennial ones in terms of variability in flow, periods of no-flow and related habitat availability.A DRIFT-ARID method (an adaptation of the Downstream Response to Imposed Flow Transformation (DRIFT) method) was developed, tested and adjusted, using the semi-permanent Mokolo River.Field data from five study sites was collected from April to May 2010 by a multidisciplinary team.The results were used in a DRIFT-ARID Decision Support System (DSS) to determine the impact of five chosen development scenarios in the Mokolo River Catchment.An integrated groundwater-surface water MIKE-SHE hydrological model was used to simulate the hydrology of the chosen scenarios.Specific non-perennial river indicators such as onset of dry phase were identified and included in the DRIFT-ARID DSS.DRIFT-ARID has the potential to be used in non-perennial rivers and, once set up, can provide results for future scenarios.The method now needs to be tested on other non-perennial river types, especially episodic rivers where data are scarce or non-existent.

Environmental water requirement (EWR) assessment methods, for ascertaining how much water should be retained in rivers to sustain ecological functioning and desired levels of biodiversity, have mostly been developed for perennial rivers. Despite non-perennial rivers comprising about 30-50% of the world's freshwater systems, data on their hydrology, biota and ecological functioning are sparse. Current EWR assessments require hydrological and other data that may not be available for such rivers and some adaptation in the methods used seems necessary. DRIFT is an EWR method for perennial (or near-perennial) rivers that has been developed in South Africa over the past two decades and is now widely applied nationally and internationally. When applied to the semi-permanent Mokolo River, challenges particular to, or accentuated by, non-perennial rivers included the reliable simulation of hydrological data, the extent of acceptable extrapolation of data, difficulties in predicting surface-water connectivity along the river, and the location and resilience of pools, as well as whether it was possible to identify a reference (natural) condition. DRIFT-ARID, reported on here, is an adaptation of the DRIFT approach to begin addressing these and other issues. It consists of 11 phases containing 29 activities.

A fully integrated, physically-based MIKE SHE/MIKE11 model was developed for the Mokolo River basin flow system to simulate key hydraulic and hydrologic indicator inputs to the Downstream Response to Imposed Flow Transformation for Arid Rivers (DRIFT-ARID) decision support system (DSS). The DRIFT-ARID tool is used in this study to define environmental water requirements (EWR) for non-perennial river flow systems in South Africa to facilitate ecosystem-based management of water resources as required by the National Water Act (Act No. 36 of 1998). Fifty years of distributed daily climate data (1950 to 2000) were used to calibrate the model against decades of daily discharge data at various gauges, measurements of Mokolo Dam stage levels, and one-time groundwater level measurements at hundreds of wells throughout the basin. Though the calibrated model captures much of the seasonal and post-event stream discharge response characteristics, lack of sub-daily climate and stream discharge data limits the ability to calibrate the model to event-level system response (i.e. peak flows). In addition, lack of basic subsurface hydrogeologic characterisation and transient groundwater level data limits the ability to calibrate the groundwater flow model, and therefore baseflow response, to a high level. Despite these limitations, the calibrated model was used to simulate changes in hydrologic and hydraulic indicators at five study sites within the basin for five 50-year land-use change scenarios, including a present-day (with dam), natural conditions (no development/irrigation), and conversion of present-day irrigation to game farm, mine/city expansion, and a combination of the last two. Challenges and recommendations for simulating the range of non-perennial systems are presented.

Reliable detailed information regarding the crop production potential of a country is necessary for the planning and execution of the proactive activities needed to avoid future food shortages due to increases in population and/or adverse climatic conditions. The land-type survey of the Republic of South Africa at a scale of 1:250 000 provides a sound basic framework for the assessment of cropping potential because the delineation criteria incorporate the three natural resource factors that determine cropping potential, namely climate, topography and soil. Assessing cropping potential at regional scales, resulted in estimates of arable area between 16.4 and 28.6 million ha. It is clear from these results that a more detailed countrywide assessment at a much larger scale is essential to provide reliable information. The procedure already demonstrated for an area of 2.7 million ha in the eastern Highveld of South Africa is recommended for this work. Modern soil survey techniques can facilitate this enormous task. Detailed assessment of the potential of the 15 million ha occupied by subsistence farmers needs to receive the highest priority. The ecotope is a suitable land unit for assessment of cropping potential. Information derived from ecotope delineation has potential to be useful in agriculture and forestry.

Changes in the demographical composition of student numbers, their educational expectations and advances in didactic formats require that educational institutions review the link between their physical learning environments and their educational visions. In general, educational visions respond to A’changing social demands and technological developments, innovations in the industry, new insights within knowledge domains, and last but not least, results from educational researchA“ (NHTV, 2014). The purpose of the current on-going study is to research changes and developments in educational goals and objectives (in response to the educational vision), and rank conceptual decision-making on creating responsive and future-proof learning environments in order of relevance and applicability to the specific educational vision in question. The current research design applies multiple methodological approaches. Part of this approach consists of a similar methodology as was discussed in earlier research on the application value of a process model for supporting decision-making in property and real estate management education (Le Roux, 2014) as was presented and the 2014 ERES conference in Bucharest, Romania. As such, this process model for supporting decision-making on organisational accommodation is applied as a central structuring element in determining educational objectives for / with new learning environments. In addition to the application of this process-model for supporting decision-making, literature on quality function development is applied to assist in the ranking of conceptual choices for elaborating and implementing solutions for future-proofing learning environments. The originality and value of the current research lies in the combination of multiple research methodologies in facilitating evidence-based decision-making on future-proof strategies and approaches to creating more responsive learning environments. This is particularly true in terms of the application of the theoretical knowledge associated with quality function deployment (QFD) in learning environments.

This paper addresses the application value of a methodology that uses an organization-centered Accommodation-Choice Model (AC-Model) for improving the match between user-requirements and organizational objectives with accommodation and/or real estate (Voordt et al., 2011).The study was performed with 150 2nd-year students during the 2012-2013 / 2013-2014 Corporate Real Estate Management (CREM) curriculum of the Academy for International Real Estate and Facility Management (IREFM) at the NHTV University of Applied Sciences in Breda, The Netherlands. Objectives of the study were: (i) introduce student-professionals to the concept of using a process model for supporting evidence-based decision-making in real estate and property management, (ii) create am awareness and in-depth understanding of the relationships between organizational ambitions and conceptual decision-making, and (iii) assess differences in take-up and application between compulsory and recommended use of the process model in problem-based learning. The methodological approach focused on applying the process model to real-life case studies where new workplace concepts have been introduced. In the 2012-2013 academic year the application of the model was a mandatory component of analyzing 6 different case study work environments, while the 2013-2014 academic year theme assignment whereby students were asked to analyze the functional optimization or transformation of existing vacant office buildings, only recommended the use of the model. In executing their assignments, groups were asked to structure the execution and outcomes of their assignments according to the process model steps.The main outcomes of the study indicate (i) the applicability of the AC-Model as a central structuring element in identifying and documenting organizational ambitions / intentions and the related conceptual choices in workplace change, (ii) the benefits of interactive learning through active application of the process model, and (iii) the added value thereof in creating and increased level of awareness and professionalism amongst students in terms of evidence-based decision-making on organizational accommodation. This research brings originality to the topic of CREM-education through the application of a decision-making support model as value-adding methodology in supporting conceptual decision-making on issues related to real estate and accommodation based on organizational goals and ambitions.