How do human activities affect watersheds negetive and positive ways ?

We negatively affect watersheds by pollution. When we litter, spray fertilizer, or use unnecessary chemicals these get washed down and enter watersheds. Therefore polluting the water and hurting the animals that live in it.

We positively affect watersheds by keeping the environment clean, and not using chemicals on our crops. Limiting water usage also is a positive affect, and managing the runoff from your home. Dirt and gross stuff gets carried out and enters the watersheds

"do a testcross with a homozygous recessive plant."