high quality / rich / good soil has a high number of nutrients / amount of nitrogen1 & high quality / rich / good soil has a high number of nutrients / amount of nitrogen2 ->  overproduction of corn can cause soil fertility to decrease  soil provides nutrients for plants & a plant requires soil for survival / to grow ->  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 ->  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 ->  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 ->  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 ->  high soil fertility has a positive impact on plants  high soil fertility has a positive impact on plants & high quality / rich / good soil has a high number of nutrients / amount of nitrogen0 ->  decreasing soil fertility has a negative impact on plants  plants are a kind of organism & organisms are a part of an environment ->  plants are a part of the environment  decreasing soil fertility has a negative impact on plants & plants are a part of the environment ->  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 -> overproduction of corn can cause soil fertility to decrease0: 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 -> overproduction of corn can negatively affect the environment by decreasing soil fertility