Which is the best example you of a direct observation

The best example of direct observation is when the researcher of animal behavior directly observe how animal lives in a reservation.

Direct observation in the type of study that allows the scientist to directly observe the phenomenon in order to understand the behavior and reactions and any response it is looking for. The researcher makes its observations in the proper environment to have better answers.

affects the water bodies: excessive use of fertilizers causes eutrophication. the fertilizers which are used on plants affect the quality of land on which it is used, further causing erosion of soil. the fertilizers used on plants contain harmful chemical fumes which affect the environment.