Advancing context-sensitive valuation of street tree benefits in contrasting urban socioeconomic settings

Source abstract

This study develops and applies a context-sensitive cost-benefit analysis (CBA) framework to quantify the economic value of street tree investments across contrasting urban socioeconomic contexts, addressing a critical gap in urban greening policy evaluation. Urban tree canopy decline threatens critical ecosystem services, particularly in socioeconomically vulnerable areas. To demonstrate the framework’s operational utility, we present a comprehensive empirical application to two contrasting municipalities in Greater Adelaide: Salisbury (lower-income, heat-vulnerable) and Unley (higher-income, dense infill). Using local council datasets and practitioner-defined scenarios, this study quantifies the costs and benefits of alternative street tree planting trajectories over a 30-year horizon (2025-2054). The valuation integrates establishment, maintenance, and externality costs with monetised benefits from amenity (property value uplift), carbon sequestration and storage, stormwater management, air pollution removal, energy and emissions savings, and avoided heat-related morbidity, using species-specific growth curves and probabilistic discounting via Monte Carlo simulation. Results show that proactive greening scenarios yield substantial positive net returns, with mean benefit-cost ratios (BCRs) of 1.26 (Realistic) and 1.37 (Optimistic) in Salisbury, and 1.36 (Realistic) and 1.47 (Optimistic) in Unley, implying that every dollar invested yields up to $1.50 in discounted societal returns. A pessimistic scenario reflecting minimal replanting delivers a BCR of 0.61, highlighting the economic cost of inaction. These findings reframe the policy conversation from whether to invest in urban greening to how and where to invest to achieve equitable, climate-resilient outcomes. The framework is therefore designed to support municipal investment prioritisation, species selection, and equitable canopy planning in climate-stressed cities.