There are two main reasons why the Earth would be worse off without decomposers:
1. Nutrient cycling: Decomposers break down dead organic matter and return nutrients back to the soil, which allows plants to grow and thrive. Without decomposers, nutrients would be locked up in dead matter, and the soil would become depleted of essential nutrients. This would lead to a decline in plant growth, which would have a cascading effect on the entire ecosystem.
2. Waste removal: Decomposers play a critical role in removing waste from the environment. They break down dead organisms and waste materials, which helps to keep the environment clean and healthy. Without decomposers, waste would accumulate and become a breeding ground for disease and pests. This would have a negative impact on the health of all living organisms, including humans.