Introduction
In the recent decades, has there been an increase or decrease in the number of vehicles on roads?
Increase!
Over the last few decades there has been an increase in vehicles on the road. This has led to increased expenditure on transportation infrastructure in order to better accommodate the amount of vehicles on the road resulting in less traffic
I had three treatment groups each with thirty plants, what is the total number of plants that were apart of the experiment?
90 Plants
For the chemical pollutants I chose motor oil and road salt, two very common road pollutants. I had one control group which received only water. Each group had 30 plants each, resulting in a total of 90 plants each. Each plant received the same amount of soil, seeds, and were watered on the same days.
What does it mean if the p-value is less than 0.05?
Results are statistically significant
No growth for both the road salt and motor oil treatment group is likely due to the fact no germination took place as a result of high concentration of pollutants. This led to the results being statistically significant meaning there was a significant difference in the health of perennial ryegrass when exposed to pollutants.
What are the three most common types of road pollutants?
Light, noise, and chemical pollutants
Road pollution encompasses several different types of pollution including light, noise, and chemical pollutants. I wanted to focus on the chemical pollutants because I was interested in the effects of toxic chemicals on plant health and growth.
What is a chlorophyll meter used for?
Evaluate chlorophyll level in a plant
A chlorophyll meter was used to test each plants chlorophyll level directly reflecting health. A high chlorophyll level indicates increased photosynthesis which is the primary energy source to fuel gluconeogenesis. The plants were given a zero for chlorophyll level if there was no growth or the growth was too little to be tested.
Which of the following answer choices is most directly effected by road pollution:
a) plants
b) soil
c) wildlife
B - soil
Pollutants likely contaminated the soil resulting in limited nutrients being supplied to the seeds. A study done in Illinois showed that plants near the tollway had reduced germination when the soil was polluted from road salt resulting in reduced plant health (Janssen, Johnson, Glass, Dickerson, Whelan & Molano-Flores 2024). Another study found that motor oil directly weakens the soil and reduces its ability to effectively provide nutrients for plants (Bolouri-Bazaz & Bolouri-Bazaz 2021). Together both of these studies indicate that chemical pollutants as a result of runoff from roadways negatively impact the soil effectively reducing germination and health of plants nearby.
What level are plants in the food chain?
Primary producers!
Plants are primary producers which means they are most essential in holding up the food chain. Without healthy plants, herbivores struggle to survive which in turn also negatively impacts the population size of carnivores. Food chains are essential to ecological communities.
What statistical test compares several independent variables to each other?
Single Factor ANOVA
I performed a single factor ANOVA test to determine if my results were statistically significant between the groups.
What would reduced plant growth have a negative impact on within the food chain?
Herbivores!
Reduced plant growth has a negative effect on the herbivores that consume plants such as deer. Knowing this connection we can focus on how to effectively rehabilitate the soil in order for plants to continue to germinate. This will restore the food chain within the ecological community near roadways.
Plant health!
I hypothesized that there will be a difference in the chlorophyll levels in Lolium perrenne (perennial ryegrass) between the treatment groups and the control group.
Which average chlorophyll level between the control group, road salt group, and motor oil group do you think would be the highest?
Control
Average chlorophyll levels were calculated for each group and were compared to each other in this bar graph. The average for the control group was 1.96. For both the road salt and motor oil treatment groups the average chlorophyll level was zero because no growth for either groups were seen.
Why is it important to consider how road pollutation affects plants?
Plants play a major role in the ecosystem, with reduced plant growth and health the entire ecosystem may suffer
Based off the bar graph, will the p-value be greater or lesser than 0.05?
Less!
The p-value was less than 0.05, degrees of freedom was equal to two, and F was 9.78.