Exploring the correlation between waterbodies, green space morphology, and carbon dioxide concentration distributions in an urban waterfront green space: A simulation study based on the carbon cycle

Urban ecological spatial patterns affect the carbon sequestration capacity of green spaces. High-resolution carbon concentration data simulated by Envi-met4.4.5 were obtained in Nanyuan Riverside Green space in Huangpu District, Shanghai. And the correlation among green space morphology factors, microclimatic and bioclimatic factors were explored by Random Forest model. The results showed that the importance of the waterfront distance factor to the carbon sink impact reaches 28.88%, and gradually decreased with the change of distance from water from south to north. The importance of the arboreal area ratio and green biomass reached 15.79% and 12.65% respectively, which was much more important than non-green vegetation space proportion indices. The importance of Cohesion reflecting green patches connectivity was 10.33%. In terms of the internal influencing microclimate factors of green space carbon cycle, relative humidity, air temperature and wind speed, had a more significant influence, with the importance degree of influence being 33.50, 29.02 and 10.29%, respectively. Compared with the influence effect between the factors of the bioclimate, the index of photosynthetically active radiation was greater than the influence of the vapor flux. The study provides a reasonable explanation for the theoretical of coupling carbon sink enhancement of hydrological and green spatial factors.