How are primary and secondary succession different from one another?

Primary succession is when there is literally nothing of the ecosystem left. Everything is wiped clean. There's barely any life sustaining soil. The area has to essentially start from scratch. Typically though this occurs when a brand new piece of land is created. The only example I can think this would occur is on a newly formed volcanic island. There's no soil, plant, or animals on a new volcanic island and has to develop from the very beginning

Secondary succession is where a previous ecosystem gets destroyed. The basic plants and nutrition filled soil is there but larger plants and animals still aren't.  I guess this would occur most likely in a fire.

Hope this helped!

european union policies. the eu's long-term objective is to achieve levels of air quality that do not result in unacceptable impacts on, and risks to, human health and the environment. eu policies aim to reduce exposure to air pollution by reducing emissions and setting limits and target values for air quality.

the main environmental problems in western europe were: energy production/acid rain, nuclear power/waste, air pollution/climate, heavy metals, pesticides, water pollution, solid waste, and unforeseen accidents. many environmental problems are common to most european countries.