What is agriculture? Agriculture is the science of farming and aspects that play a part of cultivating the soil. In Minnesota the top crops that are planted are corn and soybeans. To have a plentiful harvest, the crops need fertilizer to grow nice and strong. Sometimes during rain events and flooding the fertilizer runs off into the river and causes environmental issues.
What is fertilizer? The fertilizer farmers use is a mixture that is mostly made up of the element nitrogen. Nitrogen is very important to plant growth. It is found on tiny microscopic finger-like roots in the soil and it also is placed into the ground due to lightning striking the ground. Nitrogen is placed in the fertilizer to allow growers to have a good harvest. Then, the problem comes when that nitrogen is washed into the river.
Why is having too much nitrogen in the river an issue? Good question! Well, let’s think of it this way; Halloween is coming up and what does everyone want to do right after collecting all their delicious candy? Eat it!!! So, you begin eating all these delicious sweets and you feel great and slightly energized because of all the sugar you are eating. Then, oh no, you start to feel sick and suddenly you do not want anymore candy and even the thought of eating any more makes you feel icky. Well, this is the general idea with the river. The river likes nutrients, like nitrogen, oxygen, etc., but, if there is too much of a good thing, an issue occurs: a multitude of plant growth in the water that reduces the amount of light and oxygen to pass through all of the water. This is called eutrophication.
What can be done? Well, I had the opportunity to work as an agricultural focused intern this summer. I looked at one way to solve the issue of excess nitrogen running into the river. The company, called Geosys Inc., uses satellite imagery to look at grower fields at a certain time of the year to see how their crops are doing. Their satellite goes around the world and taking pictures of their client’s fields. The information that the satellite collects includes the geography of the field, which helps the grower see how the terrain of the field looks. Why is this important? Knowing the different levels of their fields allows the grower to know where to apply more fertilizer (higher leveled places) and where to put less (lower level areas). This helps cut away any excess fertilizer that may runoff.
Granted, this is not the only method to help stop the runoff. Scientists are testing many different ways that they could take the excess nutrients directly out of the river. Maybe one day one of you will be the one to discover the winning solution.
Have fun learning more about the environment!