In a west to east transect across the 98th meridian in the United States, which of the following is the correct sequence of soil orders?
A) Alfisols, Aridisols, Ultisols
B) Aridisols, Oxisols, Mollisols
C) Aridisols, Mollisols, Alfisols
D) Alfisols, Mollisols, Utilsols

Question

Quizplus · Accepted Answer

In general, soil orders change in a predictable sequence across a transect from west to east in the United States. In arid regions of the West, Aridisols are the dominant soil order. As the transect moves eastward, Mollisols become dominant in the grassland region of the Great Plains. Finally, in the humid eastern part of the country, Ultisols and Alfisols are dominant. Therefore, the correct sequence of soil orders in a west-to-east transect across the 98th meridian in the United States is Aridisols, Mollisols, and Alfisols.

In a West to East Transect Across the 98th Meridian