What effect would building a highway have on an ecosystem?

Answer: Building a highway would ruin the ground below the road. and the cars would pollute the area because there would be lots of cars on the highway

Impacts on Terrestrial Habitats. The impacts of roads on terrestrial ecosystems include direct habitat loss; facilitated invasion of weeds, pests, and pathogens, many of which are exotic (alien); and a variety of edge effects. Roads themselves essentially preempt wildlife habitat.