This paper investigates how different forest harvesting methods impact both the amount of carbon stored and the variety of plant and tree life. The study compared the effects of clearcutting, varying levels of partial tree retention, and no harvesting across different climatic regions in British Columbias Douglas-fir forests, ranging from humid to semi-arid. The central finding is that the intensity of harvesting significantly influences carbon storage and biodiversity, but importantly, the magnitude of these effects is strongly linked to the regional climate.