Question

Which statements are true about point and nonpoint source pollution?

Human activity causes point and nonpoint source pollution.
Only nonpoint source pollution affects abiotic factors in a watershed.
Point source pollution affects only the part of the lake or river near it.
Both point and nonpoint source pollution affect biotic factors in a watershed.
Point pollution flows through the bodies of water in a watershed but not through its land.

Answer 1

Let's evaluate the statements one by one:

1. **Human activity causes point and nonpoint source pollution.**
- **True**: Both types of pollution are often a result of human activities. Point source pollution comes from specific, identifiable sources, such as factories or wastewater treatment plants, while nonpoint source pollution arises from diffuse sources, such as agricultural runoff and urban drainage.

2. **Only nonpoint source pollution affects abiotic factors in a watershed.**
- **False**: Both point and nonpoint source pollution can affect abiotic factors. Point source pollution can introduce harmful chemicals or materials into the water, affecting parameters such as pH, temperature, and nutrient levels, which are all abiotic factors.

3. **Point source pollution affects only the part of the lake or river near it.**
- **False**: While point source pollution originates from a specific location, its effects can be felt further downstream or downstream from the source due to water movement and dispersion, potentially impacting a larger area.

4. **Both point and nonpoint source pollution affect biotic factors in a watershed.**
- **True**: Both types of pollution can have significant impacts on living organisms (biotic factors) within a watershed. For example, pollutants can harm fish populations, aquatic plants, and other wildlife.

5. **Point pollution flows through the bodies of water in a watershed but not through its land.**
- **False**: Point source pollution occurs at a specific location, and while it primarily impacts water bodies, it can also affect surrounding land through runoff and other pathways if the pollution spreads beyond its original source.

In summary:
- True statements: 1, 4
- False statements: 2, 3, 5