Beyond Ecosystem Services: Performance, Functioning, and Survival of Urban Trees

Urban forestry has experienced a rapid expansion over the past two decades, emerging as a central, interdisciplinary field bridging ecology, climate resilience, urban planning, and social-ecological systems. Past research has demonstrated the multiple benefits of urban trees and urban forests for human well-being, including temperature regulation, improved air quality, carbon sequestration, and mental health outcomes. However, this growing literature remains strongly unidirectional. It primarily focuses on how trees improve urban environments rather than on how highly anthropized, increasingly climate-changed urban environments affect the performance, survival, and long-term acclimation of trees themselves.



Cities represent novel ecosystems where environmental conditions diverge substantially from those of surrounding natural or rural areas. The urban heat island effect alters thermal regimes, often exposing trees to sustained heat stress well beyond regional climatic baselines. Further, urban soils are frequently compacted, sealed, or heavily modified, disrupting natural hydrological processes and limiting water infiltration, retention, and root development. As a result, tree species selected based on regional climate classifications may experience conditions that differ from those for which they are considered suitable. Beyond this, increasingly frequent climatic extremes may be further intensified in urbanized environments and thus present unprecedented climatic conditions.



Despite the tree’s acknowledged relevance to climate-resilient cities, our understanding of how the urban forest responds to extreme and compound climate stressors locally remains limited. Empirical data capturing long-term responses, physiological thresholds, and mortality dynamics under urban conditions are scarce, particularly under accelerating climate change. This gap reflects not only a lack of sustained monitoring data but also the fragmentation of knowledge across disciplines. Critical processes are studied in isolation, from growth reconstruction in dendrochronology to stress responses in ecophysiology, water dynamics in urban hydrology, and spatial patterns derived from remote sensing. While each of these approaches provides valuable insights, their integration remains limited.



This Research Topic aims to shift the focus toward a tree-centered perspective that explicitly addresses how urban trees navigate unprecedented environmental conditions. We invite contributions that advance a mechanistic and integrative understanding of how trees respond to biotic and abiotic stressors within cities. We particularly encourage studies that bridge scales and disciplines to understand both short-term responses and the extent to which organisms exhibit (or fail to exhibit) acclimation and long-term adaptation. We also emphasize the urgent need to expand the geographical scope of urban tree research. Evidence remains heavily biased toward temperate regions in the Global North. In contrast, climate-vulnerable regions, particularly Mediterranean and arid zones, and large cities across the Global South remain underrepresented despite facing some of the most intense and rapidly changing environmental conditions. Addressing this imbalance is critical to developing globally relevant knowledge and informing context-specific urban forest management strategies.

This Research Topic invites contributions in the form of Original Research, Systematic Review, Methods, Review, Mini Review, Policy and Practice Reviews, Hypothesis and Theory, Perspective, Data Report, Policy Brief, General Commentary, Opinion, and Technology and Code. Contributions should aim to build a more coherent and predictive understanding of urban tree responses to global change. We welcome studies employing diverse methodological, spatial, and temporal approaches:



● Remote sensing approaches to monitoring urban tree structures and function across different scales and early-warning signals of decline and mortality

● Dendrochronology and growth reconstruction in cities

● Soil-plant-atmosphere interactions in urban environments

● Root-soil interactions under constrained urban conditions, e.g., effects of soil sealing, compaction, and urban soils on tree water availability and storm water infiltration

● Tree responses to climatic trends and extremes (e.g., rising temperatures, heatwaves, droughts, floods) and their urban amplification

● Disruptions to plant–insect and plant–fungal relationships in urban environment

● Hydraulic failure, carbon balance, and narrowing down stress thresholds or tipping points are translatable for predictive frameworks of urban tree performance, to inform risk assessment, planting decision-support tools, and management strategies

● Emerging methodologies for studying urban tree responses

● Phytochemical responses

● Urban tree performance, functioning, and survival in tropical regions

● Urban tree performance, functioning, and survival in Mediterranean climates

● Urban tree performance, functioning, and survival in arid environments



Advancing this knowledge is essential to ensure that urban trees, widely promoted as nature-based solutions, can persist and continue to function under the very conditions they are expected to mitigate.