What affects the biosphere?

The short answer is "just about everything affects the biosphere."
The biosphere is the part of planet Earth where life exists. In general, the biosphere extends 8 kilometers above sea level to 8 kilometers below sea level. The biosphere is divided up into different ecosystems, and those are made up of biotic and abiotic factors. Those living and non-living things do not exist in a vacuum. Well, Earth does technically exist in a vacuum. What is meant is that each factor depends on and affects other factors in some way. There is huge interdependency within Earth's biosphere. Changes in sunlight, temperature, rainfall, etc. all affect what happens within the biosphere. This is why different ecosystems exist. Not all organisms are capable of living in each environment. Each organism has a niche to fill, which affects an area in at least one way. If that organism were to no longer exist, there would be a ripple effect toward other environmental factors. Even changes in population affect the biosphere, because the change in population changes how many limiting factors are needed within that particular region of the biosphere.
https://www.nationalgeographic.org/encyclopedia/biosphere/

https://www.windows2universe.org/earth/climate/cli_biosphere.html&edu=high