Changes to rivers and streams can happen naturally, but has increased over the years due to which kind of human activity?

Human impact on river ecosystems are:

pollution

flow modifications

exotic species

harvesting.

Human activity have great aftermath in terms of changes to rivers and streams activity and ecosystem. The interrelationship of all living organisms have within their environment is extremely complex.

The modifications in the streams and rivers have taken place naturally, however, because of the human interferences it has augmented in an uneven manner. There can be various reasons related to it, but the most important would be the development of the dam and the redirection of the flow of water.

There are various modifications done when the building of the dam is done, at certain times the natural direction of the flow of water is changed and thus, it leads to modifications in the streams and rivers.