Evaluating the influential indicators of urban agriculture with the approach of nature-based solutions to deal with urban

Introduction
Urban environments are increasingly important for providing society in terms of economy and ecosystems, and according to United Nations estimates, the world's population will reach ten billion people by 2050. Population density in compact cities creates urban challenges, both economic, social and environmental. On the other hand, these challenges have made man think of resuming the relationship with nature and in this direction, he has made various efforts. Green infrastructure is one of the most important human solutions to deal with urban challenges. One of the most effective subcategories of green infrastructure is urban agriculture. The Food and Agriculture Organization of the United Nations (FAO) has introduced urban agriculture (UA) as an effective solution in response to the increase in urban population. Because UA has the potential to provide cities that are rich in green spaces and productive in terms of food. Urban green spaces such as urban agriculture can restore diverse green infrastructure to the urban system and provide vegetative structure and biodiversity for ecosystem functioning and services across habitats and spaces. Recognizing the important role that green infrastructures and their ecosystem services play for the environment and societies, the European Commission's Directorate-General for Research and Innovation has recently introduced the concept of Nature-Based Solutions (NBS). By focusing on multiple shared benefits on the environment, economy, and society in urban landscapes, NBSs can provide more efficient and cost-effective solutions than traditional development approaches. Nature-based solutions are defined by the International Union for Conservation of Nature as measures to protect, sustainably manage and restore natural or modified ecosystems that address societal challenges (such as climate change, food and water security). or natural disasters) are investigated effectively and consistently and provide the resulting services to humans. For the implementation of innovative NBS, there is a need for integrated evaluations, which are done by evaluating indicators. In order to achieve this goal, the impact of common indicators of nature-based solutions and urban agriculture on urban challenges was investigated in this research.
Materials and methods
This research was carried out by using the questionnaire of experts (Delphi) and also using the Friedman test, and SPSS software was used to analyze the findings. The purpose of the Delphi method was to reach a consensus opinion of a group of experts on a particular topic or question and is often used in situations where there is limited or conflicting evidence, where participants may be geographically dispersed. Therefore, the Delphi panel in this study consisted of 16 experts with professional or academic backgrounds who answered 33 questions related to urban agriculture indicators and nature-based solutions in the Likert scale. To determine the level of consensus among group members, Kendall's coordination coefficient was used and the Delphi method of decision making was carried out in two phases. The purpose of multiple repetitions in the Delphi method is to reduce the range of answers and to obtain the consensus of experts, which was often more valid than guesswork or individual opinion. After ranking through the Delphi method, Friedman's test was used to rank the indicators and then the results of both methods were compared.
Findings
Delphi findings in two phases showed the positive impact of educational and aesthetic indicators and biodiversity, respectively, on urban agriculture. Due to the different mathematical formulas of the Delphi method and the Friedman test, in the Friedman test, biodiversity, education and welfare and tourism indicators were recognized as the most influential. In the first phase of the Delphi method, the social justice index did not get the necessary points and was removed from the list of indicators suitable for urban agriculture. In both methods, social justice index had the least impact on urban agriculture. Comparing the findings of both methods, it was found that the most influential indicators on urban agriculture are the common indicators between urban agriculture and nature-based solutions.
conclusion
The results of the research show the multiple advantages of urban agriculture, which have significant potential for economic empowerment and social and environmental sustainability. Among the variables examined in this research, the variables of education, food security and biodiversity, as well as aesthetics were identified as the most influential variables, respectively. Therefore, urban agriculture is considered as a flexible and cost-effective solution that covers a wide range of urban challenges and also creates extensive benefits for the well-being of citizens. It acts as a nature-based solution for sustainable urban development in dealing with urban challenges.