The comprehensive impacts of Tree-Shrub Ratio on the thermal environment, building energy consumption, and carbon-related effects in residential areas

The Tree-Shrub Ratio (TSR) Exerts a Profound Impact on Residential Microclimate, Building Energy Consumption, and Carbon Budget. This study developed a Microclimate-Building Energy Consumption-Carbon Cycle (MBECC) integrated model to systematically simulate the comprehensive effects of varying TSRS. Results indicate that different TSRS induce differentiated impacts on air temperature, relative humidity, and wind speed by modifying canopy structure and vertical distribution—with the cooling effect being the most pronounced. The all-arbor configuration outperforms other configurations in terms of overall energy conservation and carbon mitigation. When the TSR increases from 4:6 to 5:5, the enhancements in cooling, energy saving, and carbon-related effects are the most significant. In the long run, the all-shrub configuration exhibits rapid carbon sink growth in the first 20 years, whereas the all-arbor configuration surpasses it after 20 years, with its advantage continuing to expand. This study offers evidence-based guidance for the refined low-carbon design of residential green spaces.