Ecosystems Science Unit (and survey)

Aerial photo of the creek behind the school.

SCIENCE

In science class we have spent some time down by the creek behind the school learning about the creek ecosystem. Last year I revamped how I taught the Next Generation Science Standards (NGSS), which call for a study of ecosystems and the transfer of energy and matter through the plants and animals in an ecosystem. Think food webs and food chains, but with a focus on energy.

Rather than teach these ideas through “book work”, we’ve been going down to the creek that runs behind the school. Being outside helps us get a sense of the diversity (and messiness) of actual habitats, even in that small, controlled space. As we looked closely, we found slow and fast parts of the creek. We spent some time over the last few weeks sitting and observing the animals and plants that call the creek home.

About a week ago we put some microscope slides into the water in order to grow a “biofilm”, that slimy layer of microscopic organisms that cover the rocks and plants in the creek. We’ll harvest the slides this week so we can to observe yet another layer of diversity in the biosphere of the creek.

Finally, late last week we headed back to the creek to collect “macroinvertebrates”: these are the larvae of dragonflies and damselflies, riffle beetles and mayflies, caddisflies, and stoneflies, as well as the adult versions of crayfish, minnows, and water striders. These critters form a crucial part of the freshwater aquatic food web.

After studying this diversity of organisms, we’ll be ready to construct a food web and learn more about ecosystem “niches” like producers, primary and secondary consumers, decomposers/detritivores. We’ll trace the flow of energy as it goes from the Sun, through the plant world, and on to all other organisms. Later, we’ll learn how plants and animals get their energy using the systems that they contain.

Here are some photos of our time at the creek!