- Overproduction of crops can cause soil fertility to decrease
- Corn is a kind of crop
- So, overproduction of corn can cause soil fertility to decrease

- Soil provides nutrients for plants
- A plant requires soil for survival / to grow
- Hence, a plant requires nutrients in soil to grow

- A plant requires nutrients in soil to grow
- If a living thing requires something then that something has a positive impact on that living thing
- So, nutrients in soil have a positive impact on plants

- High quality / rich / good soil has a high number of nutrients / amount of nitrogen
- Fertile soil is high in quality
- Therefore, fertile soil has a high number of nutrients

- Fertile soil has a high number of nutrients
- Fertility is a property of soil that describes how fertile the soil is
- Therefore, soil with high fertility has a high number of nutrients

- Nutrients in soil have a positive impact on plants
- Soil with high fertility has a high number of nutrients
- Hence, high soil fertility has a positive impact on plants

- High soil fertility has a positive impact on plants
- Decreasing something positive has a negative impact on a thing
- So, decreasing soil fertility has a negative impact on plants

- Plants are a kind of organism
- Organisms are a part of an environment
- Therefore, plants are a part of the environment

- Decreasing soil fertility has a negative impact on plants
- Plants are a part of the environment
- Therefore, a decrease in soil fertility has a negative impact on environment

- Overproduction of corn can cause soil fertility to decrease
- A decrease in soil fertility has a negative impact on environment
- Hence, overproduction of corn can have a negative impact on the environment by decreasing soil fertility

- Overproduction of corn can cause soil fertility to decrease0
- To have a negative impact on something means to negatively affect that something
- So, overproduction of corn can negatively affect the environment by decreasing soil fertility

Hence, overproduction of corn can negatively affect the environment by decreasing soil fertility
Q: Corn is widely being used in the United States to make ethanol for use in automobile fuel. How might the overproduction of corn negatively affect the environment?
Context:
- High quality / rich / good soil has a high number of nutrients / amount of nitrogen 
- To have a negative impact on something means to negatively affect that something 
- Fertility is a property of soil that describes how fertile the soil is 
- Plants are a kind of organism 
- Soil provides nutrients for plants 
- Fertile soil is high in quality 
- If a living thing requires something then that something has a positive impact on that living thing 
- Organisms are a part of an environment 
- A plant requires soil for survival / to grow 
- Decreasing something positive has a negative impact on a thing 
- Overproduction of crops can cause soil fertility to decrease 
- Corn is a kind of crop