Biodiversity is the variety of all living things such as the different plants, animals and micro organisms, the genetic information they contain and the ecosystems they form.
biodivesity
The people need more land so they deforestate the land. So the land is harmed along with biodivesity.
biodiversity includes diversity of both flora & fauna ,i.e, plant & animal kingdom while plant biodiversityonly includes plant kingdom.
For some reason they are here, they live in a balanced ecosystem, unbalancing ecosystems, as we are finding out has greater ramifications than we originally thought. I guess my answer is to not mess too much with mother nature, or if you are religious do not mess with what God has created.