In west Texas, cotton has become an important crop in the last several decades. However, in this hot, dry part of the country there is little rainfall, so farmers irrigate their cotton fields. They must also regularly fertilize the cotton fields because the soil is very sandy. The figure below shows the record of annual productivity (measured in kilograms of cotton per hectare of land) since 1960 in a west Texas cotton field. Use these data to answer the following questions.

-Based on the information provided in the above figure, what is the most likely cause of the decline in productivity?

Question

In west Texas, cotton has become an important crop in the last several decades. However, in this hot, dry part of the country there is little rainfall, so farmers irrigate their cotton fields. They must also regularly fertilize the cotton fields because the soil is very sandy. The figure below shows the record of annual productivity (measured in kilograms of cotton per hectare of land) since 1960 in a west Texas cotton field. Use these data to answer the following questions.
 
-Based on the information provided in the above figure, what is the most likely cause of the decline in productivity?

Quizplus · Accepted Answer

The decline in productivity is likely due to the soil becoming more negative in water potential, which is a result of salination from excessive use of irrigation water. The sandy soil in west Texas is not able to retain water and as a result, the irrigation water is causing salt buildup in the soil. This leads to a decrease in water availability for the cotton plants and a decline in productivity over time. The other answer choices are less likely to be the cause of the decline in productivity based on the information provided.

In West Texas, Cotton Has Become an Important Crop in the Last