A Synthetic Review of Adaptation Strategies and Invasion Pathways in Urban Flora: Linking Ecological and Evolutionary Mechanisms for Management

Abstract

Urban ecosystems represent one of the most rapidly expanding and novel environments on Earth, characterized by a unique set of abiotic and biotic stressors. These include habitat fragmentation, pollution, the urban heat island effect, altered hydrological regimes, and frequent anthropogenic disturbance. This review synthesizes current research on how native and non-native plant species adapt to these stringent conditions and explores the critical intersection between adaptation and invasion. We first delineate the key selective pressures of the urban environment and elaborate on the specific phenotypic and genotypic adaptations observed in urban flora, including traits related to thermotolerance, drought resistance, phenology, seed dispersal, and pollution tolerance. We then investigate the pathways through which non-native species are introduced and spread in urban settings, arguing that cities function as primary hotspots and dispersal hubs for biological invasions. A central thesis of this paper is that the same traits that pre-adapt species for urban environments often overlap with those characterizing successful invaders, creating a synergistic cycle where urban areas act as filters and accelerants for invasion. Furthermore, we discuss the concept of "urban evolutionary traps" and the potential for rapid evolutionary change in both native and non-native populations. The article concludes by integrating these concepts into a management framework, proposing that understanding urban adaptation is not merely an academic exercise but is crucial for predicting invasion dynamics, conserving native biodiversity, and implementing effective greening strategies for sustainable urban futures. We highlight the need for interdisciplinary research that combines genomics, ecology, and social science to address the complex challenges of urban plant ecology.