Answer:
It causes global warming and greenhouse effect.
Step-by-step explanation:
Photosynthesis of the plants uses carbon dioxide, water, the light of the sun to produce glucose and oxygen. Carbon dioxide is the respiratory gas exhaled by all animals on the earth. Plants use it for its food making, so its amount in the earth remains constant.
As a result of photosynthesis, oxygen is formed which use by all the living organisms including the plants. Ultimately photosynthesis keeps a balance in the number of gases present in our atmosphere.
If photosynthesis stops, the carbon dioxide gas will increase in the air. It tends to trap light coming from the sun. As a result, the temperature of the earth will also increase, which will enhance global warming.
The light also comes from the sun also can't be used and helps in increasing the temperature of the earth.
The byproduct of photosynthesis i.e. oxygen can't be produced. The amount of oxygen depletes causes the death of many organisms.
Because only the green plants and certain microbes can do photosynthesis. Stopping in photosynthesis, leads to many hazards to the ecology. This is the major reason many organization encourage to plant trees.