Acid rain is rain droplets containing sulphuric oxides (SO2 and SO3) and nitrogen dioxide (NO2).
Emission is natural or human-caused processes release of material into the environment.
The pesticide is a term used to describe the human-made chemical used in agriculture to management control of the pest. The suffix “-cide” literally means “kill”, therefore, pesticide refers to a chemical substance that kills pests, insects, microbes and pathogens. And weeds has been developed; pesticides not replaced.
Thermal pollution is a term referring to water quality reduction caused by increasing its temperature. The main reason for thermal pollution is waste heat from industrial power generation processes and urban hermetical closed surfaces such as parking space.