MN STEM Notes: Increased Precipitation and River Flows

From the mighty Mississippi to our 11,842 lakes, water is central to Minnesota's landscape - and consequently our economic and social systems. Hence, understanding watershed drainage is an important and far-reaching topic in our state. Dr. Satish Gupta, Professor Emeritus in the Department of Soil, Water, and Climate at the UMN-Twin Cities, is interested in just this, with a focus on how water drains through soil and enters bodies of water.

Graphic showing two kinds of particle packing and the connection between pore spaces and capillary tubes (Gupta and Thoma, 2002. Encyclopedia of Soil Science, Marcel Dekker, Inc.) — Graphic showing two kinds of particle packing and the connection between pore spaces and capillary tubes (Gupta and Thoma, 2002. *Encyclopedia of Soil Science*, Marcel Dekker, Inc.)

Soil 'packing' is key to water drainage, even in areas that have been altered by people such as agricultural fields with tile drains. Dr. Gupta explains that central to the concept of soil packing are "empty spaces between particles called pore spaces and smaller tubes connecting these pore spaces called capillaries. Volume of pore spaces determines how much water is held in a soil and the diameter of the capillaries determines how fast the water moves to a tile drain. Since not all soil particles are of the same size, packing results in various size pores and capillaries. These variations result in different amounts of water being held and different rates of water movement to a drain tile at different soil wetness. Wet soils drain fast because water is held with less force and because it moves through bigger capillary tubes."

Dr. Gupta's recent work has investigated the connection between increased precipitation and stream flow in Minnesota. In an analysis of tile-drained watersheds in Minnesota and Iowa, Dr. Gupta and colleagues found that rises in precipitation since 1976 is the main driver of increased stream flow. Increased precipitation has also been linked to changes in the amount of nitrogen found in rivers of the Upper Midwest. As climate change results in Minnesota becoming wetter, managing river flows and nitrogen loads through wetlands will be an increasingly important topic.

MN STEM Notes is a periodic feature of the MAS newsletter designed to provide an introduction to an important topic of current research in the Minnesota STEM community.

From the MAS Archives: Evening Grosbeaks

"There is, perhaps, no bird that comes to Minnesota that is more singularly beautiful in the full perfection of its nuptial plumage, or that attracts more lively interest among all bird-lovers than the Evening Grosbeak. Fitful and uncertain in the manner of its appearance and coming unheralded, as it does, from the little known boreal region where it makes its summer home, there is ever a captivating mystery surrounding it, that adds a certain piquancy to its charm. Wild and secluded as its native haunts are known to be, unexpected tameness and confiding nature which it displays while a visitor among the dwellings of men, but serve to make it the more an object of admiration... In years gone by there was usually in the spring time a goodly assemblage of Evening Grosbeaks in the sugar maple grove on upper Nicollet Island between east and west Minneapolis, where it was an easy matter to keep in daily touch with them... They still resort occasionally to this ancient trysting place in spite of the encroachments of a big and noisy city."

Excerpt from "The Evening Grosbeak in Minnesota" by Thomas S. Roberts, published in Bulletins of the Minnesota Academy of Science, 1910

STEM from Home Resources

Keep engaged in STEM this summer! Here's some new ideas from our continually updated STEM from Home resources page:

Explore Wolf Ridge Environmental Learning Center and your own backyard with Adventures in Learning guides, experiencing nature from a variety of perspectives including science, history, culture, art, and literature
Create tree cookies for classroom teachers through the Minnesota Department of Natural Resources
Investigate groundwater contamination in your area with the Minnesota Pollution Control Agency's new Groundwater Contamination Atlas
Learn about Minnesota carnivores with this new guide from the Natural Resources Research Institute at UMN- Duluth
Print out an archaeology coloring book from the Max Planck Institute for the Science of Human History featuring real research and archaeological projects

Check out our website, facebook, and twitter for many more ways to incorporate STEM into your life!

MAS Membership Updates

Support STEM education throughout Minnesota by becoming a Minnesota Academy of Science member. MAS voting members have the opportunity to participate in elections for Board officers and influence changes to our by-laws. We offer membership levels for students, individuals, and corporations. Renew or sign up directly on our website today! Please email us with any membership questions.

Science Museum Openings

Several Minnesota science museums and zoos are now open to the public with COVID-19 safety measures in place. If you choose to attend, remember to carefully read and observe all guidelines. If you're not comfortable with an in-person visit, opportunities abound for experiencing our local scientific institutions from the comfort of your own home, check our STEM from Home page for resources!

Bakken Museum*, Minneapolis
Bell Museum*, St. Paul
Como Zoo and Marjorie McNeely Conservatory*, St. Paul
Great Lakes Aquarium, Duluth
International Wolf Center*, Ely
Jay C. Hormel Nature Center, Austin
Landsacape Arboretum*, Chaska
Minnesota Zoo*, Apple Valley

*Advanced tickets required

If you know of additional reopened scientific institutions, let us know, and we will include them in the September newsletter.

Minnesota STEM News

Renewable Energy: UMN-Morris now has a net-zero electricity carbon footprint.

Archaeology: Red pine tree-ring data reveals Anishinaabeg land use and fire occurrence in the Boundary Waters Canoe Area Wilderness.

Biological Engineering: UMN-Twin Cities researchers work to quickly generate spike proteins for COVID-19 research and vaccine development.

Wildlife Biology: Statewide project studies trumpeter swan movement using GPS transmitters.

Invasive Species: DNR removes 18 invasive carp from watershed in southwestern Minnesota.

Biology: St. Cloud State professors study the ability of amphibians to fluoresce.

Environmental Engineering: UMN-Duluth professor works to develop low-cost sulfate reduction systems for Minnesota.

Wildlife Biology: Duluth's Natural Resources Research Institute monitors frog and toad populations in Great Lakes wetlands.

Engineering: UMN-Twin Cities team develops robot to disinfect areas during COVID-19 pandemic.

Environmental Research: 2020 summer Great Lakes water temperatures are breaking records.

MAS STEM Distance Learning Survey

STEM Educators, parents, and students - how can the Minnesota Academy of Science assist you with distance learning? Please complete our short survey to help us understand your biggest challenges so we can provide helpful resources and support for STEM learning in the upcoming school year. Ideas and comments are also welcome via email.