Research and practice during the last 20 years has shown that urban agriculture can contribute to minimising the effects of climate change by, at the same time, improving quality of life in urban areas. In order to do so most effectively, land use and spatial planning are crucial so as to obtain and maintain a supportive green infrastructure and to secure citizens' healthy living conditions. As people today trend more towards living in green and sustainable city centres that can offer fresh and locally produced food, cities become again places for growing food. The scope of urban agriculture thereby is to establish food production sites within the city's sphere; for example, through building-integrated agriculture including concepts such as aquaponics, indoor agriculture, vertical farming, rooftop production, edible walls, as well as through urban farms, edible landscapes, school gardens and community gardens. Embedded in changing urban food systems, the contribution of urban agriculture to creating sustainable and climate-friendly cities is pivotal as it has the capacity to integrate other resource streams such as water, waste and energy. This article describes some of the current aspects of the circular city debate where urban agriculture is pushing forward the development of material and resource cycling in cities.

Farm diversification is of growing importance for European farmers to stabilize and/or increase their income, especially in urban and peri-urban areas. This article identifies determinants of the uptake and intensity of on-farm non-agricultural diversification such as agritourism activities, on-farm processing and direct sales activities in the Ruhr metropolitan region in Germany based on a survey among 156 farms. We find a high share of diversified farms in the Ruhr metropolitan region, often with more than one diversification activity. Environmental, farm and farmer characteristics have distinctive effects on the farmers’ diversification decision and the farmers’ decision on the diversification intensity. Younger, risk seeking farmers with secured farm succession and less productive soils are more likely to choose on-farm non-agricultural diversification. Additionally, we find that diversification intensity is positively influenced by proximity to urban areas, as well as a specialization on high value crops and the usage of extension service consultancy.

Consumer-oriented diversification activities, such as direct sale (“deepening”) as well as tourism services and care farming (“broadening”), are common business strategies of farms within urban areas. This empirical study investigates determinants of urban farming’s diversification decisions by analyzing a dataset of 123 farmers in German Ruhr Metropolis. Binary logit models are used here as econometric method to determine characteristics influencing the decision to diversify. Farm characteristics, which encourage the implementation of “deepening” strategies, are: larger farm sizes, high-value production, organic farming, and livestock production. By contrast, the consumer-oriented “broadening” strategies tourism services and care farming prevail on smaller farms and on farms with horses and higher grassland shares. Agricultural extension services increase the odds to diversify. The results of the conducted binary logistic regressions show increasing odds and predicted probabilities for “deepening” and “broadening” activities when approaching the city. Farms’ location advantages close to cities can be used best when applying consumer-oriented “deepening” or “broadening” strategies; namely, direct sale or other short supply chains, tourism services, and care farming. Viable business strategies of urban farming support a forward-looking integration into urban economy, society, and decision-making.

Dynamic land use changes in metropolitan areas are global phenomena. The influence of urbanisation processes on farmland is twofold: urban encroachments predominantly take place at the expense of farmland, and also result in farmland abandonment processes, especially in Central Eastern and Southern Europe. This paper analyses determinants of farmland abandonment in 280 municipalities situated in six selected Polish metropolitan areas. The analysis, which covers secondary statistical data as well as primary data collected via a survey among experts, applies the regression tree method. Within the six selected metropolitan areas nearly 9% of the farmland is permanently excluded from agricultural production (actual abandonment), plus another 11.5% is currently not being used for production (semi-abandonment). For actual abandonment, physical and economic sizes of farms, part-time farming, and soil quality constitute the most relevant determinants. Socio-economic variables play a more important role in explaining semi-abandonment than actual abandonment. Temporary exclusion of farmland from agricultural production is connected with urbanisation processes. Higher shares of built-up and urbanised areas, higher population densities, and positive migration rates result in higher shares of semi-abandonment. Naturally, areas characterised by agrarian fragmentation, where due to low agricultural incomes farmers more often decided to abandon agricultural production, were, in particular, subject to this process.