![Massive algal bloom](/sites/default/files/styles/resource_card_image_360x300_/public/2019-09/massive-algal-bloom.jpg?itok=pqgXB2yc)
Eutrophication: Why you should care about pond scum
STEM Explained
When fertilizers from agriculture get into lakes and rivers, big problems can result for aquatic ecosystems, food chains & webs!
![A beaver looks up from the water. Image © Jillian Cooper, iStockPhoto.com](/sites/default/files/styles/resource_card_image_360x300_/public/2019-09/A%20beaver%20looks%20up%20from%20the%20water.jpg?itok=KHUwOIhq)
Canadian Invaders!
STEM Explained
Beavers are a Canadian symbol. But in South America, they’re considered an invasive species.
![Image © TLFurrer, iStockPhoto.com](/sites/default/files/styles/resource_card_image_360x300_/public/2019-09/6675.jpg?itok=rmr9LK-v)
Are Microbes Your Friend or Foe?
STEM Explained
Microbes are everywhere, even in your digestive tract. Some of these microbes are helpful, and some aren’t.
![heavy metal band](/sites/default/files/styles/resource_card_image_360x300_/public/2019-09/Heavy_metal_band_0.jpg?itok=-Zc4rYXH)
A Taste of Heavy Metal
STEM Explained
Heavy metal is a term for some toxic chemical elements. They can cause problems like bioaccumulation, but are useful in nuclear medicine and medical imaging.
![Timea Filer - Urban Forestry Field Technologist](/sites/default/files/styles/career_image/public/2019-08/Timea%20Filer_28.jpg?itok=fEY8NK3Q)
Timea Filer (Video)
Career Profiles
Urban Forestry Field Technologist
![Timea Filer | Urban Forestry Field Technician Timea Filer | Technicienne de terrain en foresterie urbaine](/sites/default/files/styles/career_image/public/Timea%20Filer_26.jpg?itok=isJEd7as)
Timea Filer
Career Profiles
Urban Forestry Field Technician, City of Guelph
![Heather Dover | Arborist Heather Dover | Arboricultrice](/sites/default/files/styles/career_image/public/Heather%20Dover_13.jpg?itok=kijAxCZD)
Heather Dover
Career Profiles
Arborist
![Fred Sheppard | Visitor Experience Product Development Officer Fred Sheppard | Agent de développement de produits, expérience des visiteurs](/sites/default/files/styles/career_image/public/5173_13.jpg?itok=JPK62eih)
Fred Sheppard
Career Profiles
Visitor Experience Product Development Officer