Dear Colleagues,

Urban green spaces (UGS) have long been appreciated for their provisioning of multiple ecosystem services and their role in improving residents‘ health and well-being. However, in expanding cities, public parks and forests often remain underprovided; therefore, the role of other forms of green spaces, which would allow the citizens access and direct contact with nature, increases. Additionally, more attention has been given to the high cost of traditional UGS maintenance, e.g., frequent lawn mowing and its negative effects on biodiversity. Therefore, there is a need to promote more cost-efficient and environmentally friendly solutions to UGS that would allow decision-makers to expand the city’s green infrastracture, ensure UGS availability to residents, and boost ecosystem services provisioning by those areas.

The proposed Specials Issue aims at addressing research on urban green spaces beyond the typical intensively managed urban parks and forests. We are interested in the functioning of natural ecosystems in urban systems, particularly focusing on various neglected UGS, such as brownfields, wastelands, vacant lots, and other areas where natural succession processes in cities occur. As part of the Issue, we would like to include contributions regarding the adaptation of UGS to meet various goals and needs of residents and communities, including recreational needs and purposes. Studies on UGS management and innovative greenining initiatives, including public participation process, are also encouraged. Issues concerning the provision of ecosystem services, and the assessment of the cultural and ecological value of informal green spaces, will be particularly interesting. Our goal is to assess the role of informal green spaces in the process of building a model of resilient city in the face of threats resulting from climate change. Qualitative, quantitative studies, case studies, or examples of good practices will be welcome.

In this Issue, there is room for the presentation of the results of monitoring and inventory research, surveys, and modeling assessments, including stochastic and deterministic models; applications of new technologies such as aerial and satellite remote sensing; UAS photogrammetry and imaging; the use of ultrasound, geoinformation, CAD, and 3D; as well as research involving the acquisition of data from users in the crowdsourcing process on an open-call basis. There is also space for forecasting models and tools supporting the decision-making process in the field of management and protection of the natural environment of wastelands, and planning general social goals for them. We expect papers on the development of wasteland reclamation strategies and the estimation of the cost gradation of transforming them into urban green areas, and on the economic conditions increasing the level of satisfaction of users/residents with green areas located near residential buildings and in areas distant from housing estates.

By highlighting these outcomes, this Special Issue will be used to shed light on the significance of natural green spaces in urban areas to influence everyday policy and practice. The Special Issue also invites researchers of disciplines that focus on urban research, including but not exclusive to urban planning and social and environmental science.

Contributions will encompass new conceptual and empirical studies and case studies and methodological and analytical development, and will come up with particular practical implactions for UGS management and planning.

The contributions we can ensure to be submitted for the Issue cover research on informal urban green spaces particularly concerning the following:

• Analysis of the perception of informal UGS in a social environment (studies of aesthetic preferences and assessment of the impact of the surroundings on the emotional well-being of users);
• Pollution removal, in particular, the role of spontaneous vegetation in the absorption and removal of particulate matter;
• Research identifying qualities that determine the recreation potential of informal UGS;
• Examples and models of bottom-up initiatives (co-designing of space) of informal UGS into well-functioning community spaces;
• The phytoremediation of heavy metal contamination by spontaneous vegetation (copper Cu, zinc Zn, lead Pb, cadmium Cd, chromium Ce , and nickel Ni);
• Carbon dioxide absorption and related oxygen production in comparison to reference areas;
• Ecological potential of informal UGS (biodiversity mapping and bioindicators, including ground beetles, bumblebees and birds, flora and plant communities, etc.);
• The impact of invasive species on the delivery of ecosystem services;
• The role of informal UGS in adaptation of urban areas to climate change.

Prof. Jarosław Chormański
Guest Editor

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• urban green spaces
• ecosystem services
• green infrastructure