During the past few decades, vertical farming has attracted a lot of interest as an alternative food production method. Vertical farms use engineered growth environments and hydroponic cultivation techniques for growing plants indoors. One of the important factors in vertical farming for the cultivation of different plants is the amount of nutrients, which can be measured as electrical conductivity (EC). Studying the optimal EC is important for avoiding nutrient loss and deficiency in vertical farms. In this study, we investigated the effect of five EC levels (2, 1.2, 0.9, 0.7, and 0.5 dS m⁻¹) of Hoagland nutrient solution on the growth and development of basil cultivar ‘Emily’ and lettuce cultivar ‘Batavia-Caipira’. During the study, the environmental parameters were kept fixed using an automatic dosing machine. The experiment was done in automatic vertical farms using the hydroponic ebb–flow cultivation technique with a temperature of 20 ± 1 °C, relative humidity of 50–60%, CO₂ concentration of 450 ppm, pH = 6, the PPFD (photosynthetic photon flux density) of 215 ± 5.5 μmol m⁻² s⁻¹, and the photoperiod of 16:8 h (day/night). Each treatment was replicated four times. We studied the effects on several growth parameters (including the dry and fresh weight of leaves and roots, number of leaves, and leaf area) as well as the chlorophyll and nitrogen concentration of the leaves. According to the results, the basil and lettuce growth parameters among the five treatments have been significantly higher in the treatment with EC of 1.2 and 0.9 dS m⁻¹. These EC values are lower than the recommended EC value given as the optimum in the previous studies. However, the concentration of chlorophyll and nitrogen show different trends and were higher in full strength of nutrient solution with EC = 2 dS m⁻¹.

The agriculture and horticulture sector in the Netherlands is one of the most productive in the world. Although the sector is one of the most advanced and intense agricultural production systems worldwide, it faces challenges, such as climate change and environmental and social unsustainability of industrial production. To overcome these challenges, alternative food production initiatives have emerged, especially in large cities such as Amsterdam. Some initiatives involve producing food in the urban environment, supported by new technologies and practices, so-called high-tech urban agriculture (HTUA). These initiatives make cultivation of plants inside and on top of buildings possible and increase green spaces in urban areas. The emerging agricultural technologies are creating new business environments that are shape d by technology developers (e.g., suppliers of horticultural light emitting diodes (LED) and control environment systems) and developers of alternative food production practices (e.g., HTUA start-ups). However, research shows that the uptake of these technological innovations in urban planning processes is problematic. Therefore, this research analyzes the barriers that local government planners and HTUA developers are facing in the embedding of HTUA in urban planning processes, using the city of Amsterdam as a case study. This study draws on actor-network theory (ANT) to analyze the interactions between planners, technologies, technology developers and developers of alternative food production practices. Several concepts of ANT are integrated into a multi-level perspective on sustainability transitions (MLP) to create a new theoretical framework that can explain how interactions between technologies and planning actors transform the incumbent social–technical regime. The configuration of interactions between social and material entities in technology development and adoption processes in Amsterdam is analyzed through the lens of this theoretical framework. The data in this study were gathered by tracing actors and their connections by using ethnographic research methods. In the course of the integration of new technologies into urban planning practices, gaps between technologies, technology developers, and planning actors have been identified. The results of this study show a lacking connection between planning actors and technology developers, although planning actors do interact with developers of alternative food production practices. These interactions are influenced by agency of artefacts such as visualizations of the future projects. The paper concludes that for the utilization of emerging technologies for sustainability transition of cities, the existing gap between technology developers and planning actors needs to be bridged through the integration of technology development visions in urban agendas and planning processes.

The continuing decline of arable land per person and global human population growth are raising concerns about food security. Recent advances in horticultural technology (i.e., growing using light-emitting diode (LED) lighting, hydroponics, vertical farming, and controlled environments) have changed the ways in which vegetables can be produced and supplied. The emerging technology makes it possible to produce more food using fewer resources, independent of the weather and the need for land. They allow bringing agricultural practices inside urban built up spaces and making horticultural production an integrated part of the daily life of urban residents. However, the process and consequences of this technology-driven transition on urban planning and development are hardly understood. This paper uses the theory of multi-level perspective (MLP) on sustainability transitions and actor–network theory (ANT) to explore this technology-driven transition and its adoption in urban planning and development. The high-tech horticulture zone development in Shanghai was used as a case study. The results show the importance of both social (i.e., policymakers and planners) and material (i.e., technologies and policy documents) actants in the transition of the sociotechnical regime. Furthermore, the transition toward sustainable urban horticulture practices requires the simultaneous preparation of supportive and compatible spatial development, agricultural and sustainable development policies, and adequate policy implementation and evaluation tools to increase the competitive strength of innovative practices.

We analyse the action space for strategic planning and sustainability transition among planners in Swedish municipalities. We use qualitative and quantitative materials from 103 survey responses obtained from Swedish municipal planners. Our analysis shows that the size and type (e.g. population and density) of the municipality where the planners work are connected to their perceived action space, where policies for densely populated cities are less relevant for rural municipalities. Even if size matters for the action space for sustainability transition, this action space can be modified (e.g. access to resources and participation in networks) and continuously constructed.

The agricultural sector in developing countries is one of the most vulnerable sectors to climate change and water scarcity. Iran is one Middle Eastern country facing a growing water crisis. Rafsanjan county, located in the province of Kerman, is losing its pistachio orchards to water shortages and climate change. The modernisation of irrigation methods and transfer of water from other regions have been the main strategies taken by the governmental authorities. The lack of success of these strategies has led to the emergence of more participatory approaches in the transformation of the agricultural sector and local urban planning in Rafsanjan. This study analyses the actor network of transformation in the agricultural sector and the rise of high-tech urban agriculture, and aims to understand the role of technologies in supporting citizen participation in local urban planning. The research draws on the concept of Technology-Driven Transitions (TDT). The interactions among social and materials entities and the impact of technological novelties on the re-configuration of their relationships in the transition process were studied. The research comprised an exploratory case study, and data were gathered through observations, document study and in-depth interviews with farmers, planners, researchers, and policy makers in Rafsanjan. The results of the study show that governmental planning organizations and their implementation bodies, such as the Agricultural Research, Education and Extension Organization (AREEO) and the 10-year plan for the development of greenhouses, were the most influential actants in the transition process. Their relationships with the other actants involved, such as the private sector, knowledge institutes and farmers, were re-configured by technological novelties. This re-configuration of relationships has led to strengthened participatory decision making in local urban planning in Rafsanjan.

To achieve their goal to become climate neutral, Swedish municipalities must significantly improve their transformative capacities. Adapting the roles and practices of urban planners is an important element in this process. This paper critically reflects on the way in which improved planning education may help to enable a new generation of planners to face the challenges of rapid urban transformation and provides them with the knowledge and tools needed for these new roles. The results suggest that there are interdependencies between the demand of municipalities for knowledge and skills and the capacity of educational programs for educating planners with transformative abilities.