Science Fair Research Paper

Impact of Light Intensity on Plant Growth

Researcher: [Your Name]

Introduction

The interaction between light intensity and plant growth is a fundamental topic in botany and agriculture. This research paper aims to explore how varying levels of light intensity affect the growth and development of plants. Understanding this relationship can help optimize agricultural practices and improve crop yields.

Background

Plants rely on light for photosynthesis, the process by which they convert light energy into chemical energy. Light intensity, along with wavelength and duration, significantly impacts photosynthesis. Previous studies have shown that insufficient light can lead to poor growth and development, while excessive light can cause damage to plant tissues.

Research Question

How does varying light intensity affect the growth of plants?

Hypothesis

If the light intensity increases, then the plant growth rate will increase up to a certain point, beyond which the growth will decrease due to light saturation or damage to plant tissues.

Materials and Methods

To investigate the impact of light intensity on plant growth, the following materials and methods were used:

Plants: Arabidopsis thaliana (model organism)
Light sources: LED grow lights with adjustable intensity
Growth medium: Standard potting soil
Measurement tools: Ruler, scale, and chlorophyll meter
Experimental setup: Plants were split into three groups with different light levels.

Data Collection

The following parameters were measured over a period of 30 days:

Plant height (cm)
Number of leaves
Chlorophyll content (SPAD units)
Biomass (g)

Results

Parameter	Low Light	Medium Light	High Light
Plant height (cm)	10.2	15.8	14.6
Number of leaves	8	12	11
Chlorophyll content (SPAD units)	28.4	35.6	33.2
Biomass (g)	1.5	2.8	2.4

Discussion

The results indicate that medium light intensity led to optimal plant growth, as evidenced by the highest plant height, number of leaves, chlorophyll content, and biomass. Plants under low light conditions showed stunted growth, while those under high light intensity exhibited signs of stress, such as reduced chlorophyll content and lower biomass compared to medium light conditions.

Conclusion

The hypothesis was supported by the data. Medium light intensity promoted the best overall plant growth, while low and high intensities were less effective. These findings underscore the importance of optimizing light conditions for plant cultivation to enhance growth and yield.