Answer:
Water resources face a host of serious threats, all caused primarily by human activity. They include pollution, climate change, urban growth, and landscape changes such as deforestation. Each of them has its own specific impact, usually directly on ecosystems and in turn on water resources.
Step-by-step explanation:
Sedimentation.
Runoff.
Erosion.
Dissolved oxygen.
pH.
Temperature.
Decayed organic materials.
Pesticides.