It will put people with homes situated beside shorelines at risk as cliff collapse can lead to the deterioration of any land located beside the cliff in question which can rapidly progress towards civilization as the erosion effects the lower levels of minerals and other geological things such as soils or rocks & Cliff collapse affects the environment around it because that cliff may have had food essential to certain species. Also, organisms may have habitats on the collapsed area, and now it is lost due to the cliff collapsing. Things in nature have chain reactions, so if one thing is affected, other things will get affected as well (the food chain can be negatively effected)