How have humans modified the environment and how those modifications have impacted society ?

humans have modified the physical environment by clearing land for agriculture or damming streams to store and divert water. This impacts the communities and wildlife located downstream who might depend on that water.

Explanation:

early settlements on the subcontinent. both the indus and the ganges rivers carried rich silt from the mountains to the plains. when the rivers flooded, the silt spread over the plains and made the soil in the river valleys fertile for farming.

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