Nature-based Solutions for improving ecosystem services from vacant lands in a coastal city

Coastal cities are facing unexpected repercussions due to climate change. Thus, it is urgent and necessary to introduce nature-based solutions to enhance ecosystem services. However, since most coastal cities are highly urbanized and fully densified, it is difficult to find spaces to apply nature-based solutions. In this context, this study focused on vacant lands as alternative spaces, abandoned and remnant areas with high biodiversity and ecological values. This study aimed to evaluate how adopting nature-based solutions in vacant lands might improve ecosystem services including carbon storage, flood control, air quality control, and building energy saving. This study selected Seoguipo-si of Jeju-do as a study site because this city is considered as one of the cities most vulnerable to the effects of climate change in South Korea. First, this study investigated the social-ecological characteristics of vacant lands, such as geographical data, specification of trees and shrubs, vegetation composition, and land-use patterns. Then, this study determined that the study area had six types of vacant lands including (1) unmanaged vegetation with no grass, (2) single tree with grass cover, (3) street trees, (4) multi-layered vegetation, (5) single-layered vegetation, and (6) mini-lot vegetation. Second, this study assessed and simulated the improvement of ecosystem services according to types of vacant lands, planting strategies, and budget levels of nature-based solutions. The results show that prioritizing the introduction of multi-layered vegetation in areas vulnerable to climate change helped improve ecosystem services. Also, it was found that the higher the budget, the better the ecosystem services in vacant lands of the study area. Based on the results, this study suggested specific restoration strategies for applying nature-based solutions to vacant lands in the coastal city. The findings of this study can contribute to a deeper understanding of the novel role that vacant lands play in building coastal resilience. Also, the evidence-based design for adopting nature-based solutions conducted in this study may provide the basis for climate adaptive urban planning with limited budget and spaces.

Funding: This research was suported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education(NRF-2022R1A6A3A01087632).