The Effect of Sunlight on Biomass

Topic: The Effect of Sunlight on Biomass

Aim: To investigate the difference in biomass due to exposure to sunlight

Research question: How does sun exposure affect above ground dry biomass of grass?

Apparatus:

• ½ meter square quadrat
• 10 plastic bags
• Knife
• Scale
• Labels

Method:

1. Label plastic bags from one to ten. Let one to five be for shaded and six to ten for unshaded regions.
2. Various areas around the school that are either shaded or exposed to sunlight throughout the day were chosen.
3. In any of the shaded regions a ½ meter squared quadrat was thrown randomly within the boundaries of the area.  
4. Each ½ meter squared quadrat was divided into four (¼ meter squared) and any random square was chosen to sample grass from.
5. A knife is then used to cut all the grass within the ¼ meter square and collected in plastic bag labelled one.
6. This is repeated in the other shaded regions around the school until five bags are collected
7.  This is repeated for the unshaded regions.
8. The mass of the grass in each bag was then measured using a scale and recorded.
9. Each grass sample was placed in specific trays and dried in the sun for two days.
10. After two days passed the new masses of all grass samples was measured and recorded.

Variables:

• Independent variable

• Sun exposure

• Dependent variable

• Dry biomass

• Other variables

• Amount of water

Qualitative data:

• Grass in shaded areas appeared greener than grass in areas exposed to the sun
• When grass was placed in plastic bags after some time water droplets formed on the inside of the bags
• More water was observed in bags with shaded grass than in bags with grass that was not shaded
• Change in mass observed in shaded grass samples was generally greater than in the not shaded regions

Quantitative data:

The change in Biomass of Collected Grass