Benefits:
- Improve Land Fertility
- Create new islands and land
- Provide habitat to pioneer species
- Create economic mineral deposits
- Create beautiful landscapes
- Generate tourism
- Atmospheric cooling
Harmful effects:
- Harmful Gases
- Habitat loss and Destruction
- Destroy old habitat and crops
- Destroy cities, towns, communities
- Displace populations
- Kill people and other animals
- Disrupt commerce
Sana makatulong:-)
P. S. Just make this answer as a guide.