Contribution of urban trees to carbon sequestration and reduction of air pollutants in Lima, Peru

Abstract

Urban green areas, such as parks, squares, and tree-lined streets, are part of nature-based solutions (NBS) that provide ecosystem services to address these urban issues. However, there is limited knowledge about the contribution of tree species and overall ecosystem services provided by urban trees under public management, especially in Latin America. This study aimed to provide information on the contribution of urban trees in reducing highly incident pollutants, such as CO2, particulate matter (PM 2. 5 and 10), and greenhouse effect gas compounds (GEG) in the city of Lima (Peru), using the I-tree package software tool for estimating ecosystem services. The results demonstrate that urban trees under public management in Lima significantly contribute to pollutant reduction and the sequestration and storage of CO2 in the city, being that storage is nearly 50% of the levels observed in native temperate forests in Latin America and higher than the value measured in some xerophytic native forests in the same region. Other evaluated pollutantś levels are significantly reduced. Differences among tree species were observed, showing amatillo (Ficus pertusa L. f.) and red eucalyptus (Eucalyptus camaldulensis Dehnh.) as higher contributions to pollutant reduction, with Erythrina falcata Benth. as a native species having significant carbon storage (1,27 t/individual). This information is highly relevant for professionals and public institutions involved in urban planning and management, particularly urban tree management. It shows that tree species selection influences the mitigation of pollutant levels in cities while increasing other ecosystem services, thereby contributing to improving citizens' health.