I guess machinery used to cut down trees can use fossil fuels, they also transform co2 into sugar, cellulose and other carbon-containing carbohydrates.
Deforestation increases the amount of CO2 in air which is one of the greenhouse gas. Increased CO2 level in air causes global warming.
Explanation:
Plants absorb CO2 from the air for photosynthesis and maintain the CO2 level of the air. Deforestation removes plants resulting in increased CO2 level of air as fewer plants are available to absorb the gas from the air.
CO2 is one of the greenhouse gas which traps the radiations reflected back by earth surface at night and causes an increase in global temperature of the earth, that is, global warming.
