In a large-scale study comparing plant distributions in the western United States, researchers observed that over 70% of studies plant species shifted to different elevations over the past 100 years. Which of these could be an environmental factor that affected the shift in ecology for the plant species across different elevations? Select ALL that apply.

Question

In a large-scale study comparing plant distributions in the western United States, researchers observed that over 70% of studies plant species shifted to different elevations over the past 100 years. Which of these could be an environmental factor that affected the shift in ecology for the plant species across different elevations? Select ALL that apply.
Responses
A	Precipitation levels are higher at different elevations, providing more water as a reactant in photosynthesis.Precipitation levels are higher at different elevations, providing more water as a reactant in photosynthesis.
B	Light levels are increased at different elevations, allowing the plant to perform more photosynthesis for growth.Light levels are increased at different elevations, allowing the plant to perform more photosynthesis for growth.
C	Temperatures are more conducive for growth at different altitudes compared to other, colder altitudes and elevations.Temperatures are more conducive for growth at different altitudes compared to other, colder altitudes and elevations.
D	Carbon dioxide levels are higher at different elevations, allowing the plant to perform more photosynthesis for growth.Carbon dioxide levels are higher at different elevations, allowing the plant to perform more photosynthesis for growth.
E	Oxygen levels are higher at different elevations, requiring the plant to perform more cellular respiration, which competes with photosynthesis to affect plant growth.
Oxygen levels are higher at different elevations, requiring the plant to perform more cellular respiration, which competes with photosynthesis to affect plant growth.

GPT-4o mini · Answer

In the context of the study addressing shifts in plant distributions due to environmental factors, the following options could be relevant:

A. Precipitation levels are higher at different elevations, providing more water as a reactant in photosynthesis.
This could affect plant growth positively, as water is essential for photosynthesis.

B. Light levels are increased at different elevations, allowing the plant to perform more photosynthesis for growth.
This is true for certain elevations but not universally, as light levels can vary depending on other environmental factors, such as canopy cover. However, in many cases, higher elevations do receive more direct sunlight due to thinner atmosphere and lower vegetation density.

C. Temperatures are more conducive for growth at different altitudes compared to other, colder altitudes and elevations.
This is a valid point; shifts in temperature due to climate change can lead plants to migrate to areas with more favorable growing conditions.

D. Carbon dioxide levels are higher at different elevations, allowing the plant to perform more photosynthesis for growth.
Typically, CO2 levels do not significantly vary with elevation in a manner conducive to affecting plant distribution, as they tend to be fairly homogeneous in the atmosphere.

E. Oxygen levels are higher at different elevations, requiring the plant to perform more cellular respiration, which competes with photosynthesis to affect plant growth.
This is incorrect; oxygen levels generally decrease with elevation. Higher elevations can indeed create stress for some plants, but the claim about higher oxygen levels is inaccurate.

In summary, the relevant environmental factors that could have affected the shift in plant species distributions across different elevations are:

A (Precipitation levels)
B (Light levels)
C (Temperatures)

Thus, the correct answers are A, B, and C.