I believe all of the above!
It can affect our ecosystem in many ways, think about the animals. Where are they going to live? If trees, get demolished to create a hotel, or a gas station.
The signal Hawkeye and the men agreed on while nearing the Huron encampment were three croaks of a crow.
Hawkeye tells his men to scout the area and in the case that they or he find something, they should use the signal in the form of thee croaks of a crow to warn the others about the danger. However, the only thing he finds in the encampment are a couple of Indians.
Photosynthesis reverses the biochemical pathways of respiration.