From the deputy editor

In his classical book, ‘Cities of tomorrow: An intellectual history of urban planning and design since 1880’, the late, Professor Sir Peter Hall presents a critical history of planning theory and practice in the twentieth century. The critique is linked to the socio-economic constraints and opportunities that emerge and are emerging in advancing the city artefact as a civilising tool. In essence, humankind has been consumed by the need to make great places that are able to serve humanity’s changing needs and expectations

From the guest editors

Cities are engines of socio-economic growth and development. In facilitating this growth, cities have been notorious for delivering inequality and spatial imbalances, spatially accentuating the socio-economic population groups’ differences across income groups, social class, gender, minorities, and vulnerable groups, and thereby impacting on spaces, places, cultures, inclusion, and diversity. Perhaps, more challenging, and subtle but starkly disappointing has been that cities have been efficient machines in ejecting approximately 70% of greenhouse gas emissions on this planet (Xue, 2022: 102699). This is a great concern in a context in which over half of humanity (this figure is projected to reach 68% by 2050) lives in urban areas (Wheeler, 2021: 10). The onslaught of climate change is meeting our biggest urbanisation and settlement dynamics wave and drive in human civilization, as millions of people continue to migrate into cities in the hope of a better life. This phenomenon and momentum do not seem to show any signals of slowing down soon and is occurring despite the reality that many of our cities are already showing cracks and gaps in respect of their ability to act on climate change and impacts. The need to achieve net zero CO2 emissions in future makes the call for climate action an urgent priority for all

Water Marginality in Rural and Peri-Urban Communities

Water supply in an increasing number of rural and peri-urban communities can be described as marginal i.e. subject to failure, becoming unaffordable or increasingly difficult to access. A range of common factors contribute to water marginalisation or access bias. Firstly, communities may be poorly served by formal water infrastructure by being on the margins of urban settlements. Secondly, where water infrastructure exists, this may be prone to failure as local municipalities and water utilities with limited capacity and resources struggle to maintain a widely dispersed system. Thirdly, when local water systems fail, they are often not repaired quickly, if repaired at all. This results in people, often with very limited resources having to obtain water from far distances or having to pay someone to transport water to them in order to meet their basic water needs. Thus, where water supplies are unreliable, unaffordable and difficult to access, geography, urban settlement patterns, the choice of water distribution systems, and the management capacity result in water marginality. This paper investigates water marginality in communities in rural and peri-urban areas in South Africa. It utilises surveys and interviews of communities, the local authority, water and urban planning officials, to understand the nature of this marginality, and investigates the key contributory factors. This forms the basis for recommendations on how access and marginalisation challenges can be addressed. The paper provides valuable insights on how, and why, water marginality occurs, and proposes strategies for sustainable solutions. As climate change and rural-urban migration accentuate water marginality, the study offers important and timely insights in an area that urgently requires further research.</p

Restructuring Gauteng City Region in South Africa: Is a Transportation Solution the Answer?

The Gauteng city region forms the economic hub of socio-economic development and growth in South Africa. The province itself includes the Johannesburg metropolitan city, Ekurhuleni metropolitan city as well as Tshwane municipality—key urban growth regions of Gauteng province, South Africa, and by extension Southern Africa. The region exhibits the rapid urbanisation challenges typical in any developing country city. Rural–urban migration, pressure on infrastructure demand, supply and capacity constraints and mismatches in urban governance structures with respect to service delivery have remained stubborn challenges. Initiatives and strategies to resolve urban traffic congestion such as through road construction and highway expansion (physical instrument), e-tolling of roads (financial instrument), innovative housing and waste management technology deployment (technology instruments) as well as presenting advanced spatial planning and development and management systems (planning and regulatory instruments) have been employed with mixed fortunes in attempts to (re)solve the urban problems in the study area. Making use of a thematic approach and technique, the major urbanisation issues are explored and solutions proffered. Recommendations revolve around the need to implement robust and progressive rafts of projects, programmes, activities, measures and actions to reverse spatial fragmentation and spatially inefficient transport induced and perpetuated disadvantages

Diffusional exchange versus microscopic kurtosis from CTI: two conflicting interpretations of the same data

Correlation tensor imaging (CTI) is a new diffusion MRI framework that utilises double diffusion encoding (DDE) to resolve isotropic, anisotropic and microscopic kurtosis sources. Microscopic kurtosis in CTI is provided by the contrast between SDE and parallel DDE signals at the same b-value. Multi-Gaussian exchange (MGE) is a diffusion MRI framework that utilises DDE to measure exchange. The highest exchange sensitivity in MGE is obtained by contrasting SDE and DDE signals at the same b-value. CTI and MGE can thus be applied to analyse the same data but provide conflicting interpretations of that data. We perform Monte Carlo simulations in different geometries with varying levels of exchange to determine which approach is more compatible with the data. Simulations reveal that in all microstructures considered, CTI microscopic kurtosis drastically increases when exchange is introduced. Furthermore, in microstructures that are well-described by the multi-Gaussian assumption, CTI-estimated microscopic kurtosis increases with both the exchange rate and the mixing time, despite fulfilment of the long-mixing-time condition of CTI. Increasing the exchange rate by a factor of 2 positively biases CTI microscopic kurtosis by approximately the same factor. At a modest exchange rate of 10 /s, varying the mixing time from 12 to 100 ms increases CTI microscopic kurtosis by at least a factor of 3. To address this problem, we propose a heuristic approach to combine CTI and MGE to estimate intra-compartmental kurtosis unconfounded by exchange and demonstrate its feasibility using numerical simulations

Vendor and pedestrian experiences of their ‘right to the city’ in street design and management in small urban centres in the Vhembe District, South Africa

The demand for a spatial turn to enhance citizens’ ‘right to the city’ is gaining more momentum in this era than previously. This is particularly evident within the South African urban space context. This article examines the vendor and pedestrian (street users) experiences of their ‘right to the city’ in street design and management in small urban centres in the Vhembe District of South Africa. The article adopted a case-study survey design and a mixed methods research approach. Data was collected by means of both key informant interviews with eight key experts in street design and management and a street intercept questionnaire survey administered to a total of 100 vendors and 400 pedestrians in the selected case study towns. Data analysis was done quantitatively through average users’ satisfaction scores with a spatial quality and qualitatively through thematic analysis. Lefèbvre’s ‘right to the city’ theory was used to extract meaning from the research findings. The findings reveal that street users in all the towns of the study are dissatisfied with the spatial quality of safety, while accessibility was a challenge particularly in Thohoyandou Town. The findings reveal that economic, historical, and geographical differences affect street users’ ‘right to the city’ experiences. Questions such as “Whose ‘right to the city’?” and “Which ‘right to the city’?” remain paradoxical. To create more spatially just streets, where vendors and pedestrians can enjoy their disparate ‘right to the city’ claims, users need to embrace the right to differences and municipalities in small urban centres need to continue to learn, experiment, and co-create urban space with the vendors and the pedestrians

Production and Resource Use of Winter Feed Crops in New Zealand

In the South Island of New Zealand (NZ), dairy cow numbers have increased from 1.4 to 2.1 million since 2005 (Statistics, New Zealand, 2014). This has led to a strong demand for winter feed crops in place of pasture, and also for supplementing pasture during lactation. Yields of 19–35 t DM/ha are reported for fodder beet (Beta vulgaris L.) in NZ (Chakwizira et al., 2014) compared with 14–25 t DM/ha for forage kale (Brassica oleracea L.) (Chakwizira et al., 2009) and 18–25 t DM/ha for maize (Zea mays L.). Fodder beet has only recently been widely adopted for its ease of feeding and provision a high energy feed (Matthew et al., 2011). Choice of crop is based on yield potential, feed value and suitability for winter feed management. Nitrogen fertiliser and irrigation practices affect the productivity, profitability, and dynamics of resource use during crop growth; and losses of N during winter in situ feeding. Optimized systems with high water and N use efficiency are sought to reduce potential adverse environmental effects. The objectives were to compare efficiency of water and N use of fodder beet, kale and maize and assess their value to growers

Policy directions for spatial transformation and sustainable development: A case study of Polokwane City, South Africa

South African cities are faced with complex challenges of facilitating spatial transformation, in order to redress the negative spatial implications of the apartheid planning legacy. Efforts aimed at an improved understanding of the legislative policy contribution in respect of promoting sustainable urban development has been biased towards major cities at the expense of secondary, small medium-sized towns in the world. This article seeks to contribute to the debate on sustainable urban development by drawing empirical experiences on legislative policy directions for spatial transformation in Polokwane, an intermediate city in South Africa. A literature review method, underpinned by the pragmatic research paradigm, was adopted in this article. A database with a total of 116 documents was established from files collected during expert interviews and additional literature from Google, Google Scholar and library databases – EBSCOhost, JSTOR, Web of Science. Twenty-eight papers, dissertations, as well as legislative and policy framework plans were identified as relevant for review, through a thematic analysis approach guided by deductive reasoning. Lefebvre’s production of space theory, the spatial triad and discourse analysis constituted the theoretical framework in analysing Polokwane City’s legislative policy directions with respect to spatial transformation and sustainable urban development covering the period 1996-2016. Findings show that spatial transformation legislative policy systems play a framing role in Polokwane City, in terms of promoting urban containment as a practical sustainable urban form-making and shaping tool to ensure sustainable urban development. This resultant ‘desired and crafted’ urban form is implemented through strategic development areas, spatial targeting, housing development, densification, sustainable transport, greening, and smart city concept

The state of rural transport research in South Africa - gauging the policy shifts : 1994 - 2014

This paper explores the state of rural transport research in South Africa covering the period 1994 -2014 with a particular focus on gauging the policy shift. The sustainable development theoretical framework is employed as the over-arching analytical tool. The paper draws from an extensive desktop literature review of rural transport policy research output accessible in the public domain covering the twenty year period. The main findings confirm a discernible transport paradigm shift underpinned by contestations regarding rural transportation policy planning and implementation. The paper also discusses rural transport research blind-spots and opportunities for valorizing the research output for the benefit of rural communities across the country.Paper presented at the 34th Annual Southern African Transport Conference 6-9 July 2015 "Working Together to Deliver - Sakha Sonke", CSIR International Convention Centre, Pretoria, South Africa.The Minister of Transport, South AfricaTransportation Research Board of the US

The Manifestation of Street Safety and Security as Spatial (in)justice in Selected Small Rural Towns of Vhembe District, South Africa

Safe and secure street spaces for pedestrians translate to spatially just urban environments. This study examined pedestrians' safety and security elements on street spaces in three selected Small Rural Towns (SRTs) in South Africa and assessed the users' physical perceptions of street safety and security in SRTs and their implications on spatial (in)justice. Forty-three street spaces from three SRTs in South Africa were purposively sampled and assessed in this study. The study adopted a mixed-method approach involving the use of a case study and a survey. &nbsp;Data were collected through key informant interviews, a questionnaire survey and a street space design quality checklist. The distribution of safety and security elements across the studied 43 street spaces reflect the existence of justices and injustices concurrently. Users' theoretical perception of the meaning of street safety differs significantly from their actual experiences. The study recommends that the design and management of streets be informed by users' vision of street safety and security, as well as innovative project financing strategies to ensure spatial justice on street spaces