Percentage of photosynthetically active radiation (PAR) in the incident solar radiation is

Options

A. 1-5%
B. 2-10%
C. less than 50%
D. approx 100%

Explanation

To solve the question regarding the percentage of photosynthetically active radiation (PAR) in the incident solar radiation, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding Solar Radiation**:
- Solar radiation is the total energy emitted by the sun, which includes a wide range of wavelengths.

2. **Definition of Photosynthetically Active Radiation (PAR)**:
- PAR refers to the portion of solar radiation that plants can use for photosynthesis. This is specifically the light in the wavelength range of approximately 400 to 700 nanometers.

3. **Percentage of PAR in Solar Radiation**:
- It is known that about 50% of the total solar radiation falls within the range of PAR. This means that if we consider 100% of the incident solar radiation, around 50% of it is classified as PAR.

4. **Clarifying Common Misconceptions**:
- While it is true that plants capture only about 2 to 10% of the PAR for photosynthesis, this percentage refers to the amount of PAR that is utilized by plants, not the percentage of PAR itself in the incident solar radiation.

5. **Final Answer**:
- Therefore, the percentage of photosynthetically active radiation (PAR) in the incident solar radiation is approximately **50%**.