Q29.3-4ITD. - Campbell Biology

Question

Based on their experimental results, the researchers added weathering of rock by non-vascular plants to simulation models of the Ordovician climate. The new models predicted decreased CO₂ levels and global cooling sufficient to produce the glaciations in the Late Ordovician period. What assumptions did the researchers make in using results from their experiments in climate simulation models?

 

Step-by-Step Solution

Answer

The assumption made by researchers was that the chemical weathering of rocks by Ordovician moss was similar to that of weathering caused by modern moss patterns. The assumption, such as the area of land colonized by non-vascular plants during the Ordovician period, was also made by researchers.

Step:1: Experiment performed by researchers

The researchers performed an experiment to find the effect of non-vascular plants such as moss on weathering of rocks. To find its result, they added macerated moss to the rocks and found that chemicals present in moss increase weathering of rocks.

Moss also increases the release of elements such as calcium and magnesium from rocks. 

Step 2: Assumptions made by researchers

The researchers made two major assumptions when they added weathering of rocks by non-vascular plants to stimulation models of Ordovician climate. They assumed that the effect of chemical weathering by Ordovician moss was similar to the chemical weathering done by modern moss patterns. 

The other assumption was the land area colonized by non-vascular plants such as moss during the Ordovician period. The second period of the Paleozoic Era is called the Ordovician period. 

Step 3: Conclusion of result

The experiment concluded that the chemical weathering of rocks by non-vascular plants such as moss reduces carbon dioxide levels of the atmosphere. Thus, moss also affects atmospheric carbon dioxide levels.