When forests are clearcutted, the amount of trees is dramatically reduced, which results in an important reduction of the transformation of CO2. Therefore, limiting the production of oxygen.
Deforestation rates in the Amazon have increased over the last decade. When forests are clearcutted, the amount of trees is dramatically reduced and it results in a reduction of the transformation of CO2, therefore increasing the presence of gas emissions.
The Amazon rainforest is one of the most diverse places on Earth. The rates of deforestation have caused the significant and worrying decline of biodiversity and also it has led to a loss of over 17 million hectares of ecologically and economically important species of plants. This loss leads to the depletion of vital resources such as medicine and freshwater supply. In addition, it leads to increased temperatures which have a detrimental impact on biodiversity declines and human health.
i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.