WHAT IS NATURE
HOW NATURE WORKS: FOOD CHAIN AND ENERGY FLOW
The Four Laws of Ecology
1. Everything is connected to everything else: Life relies on other life. Trees give us shelter from the weather, bees pollinate plants, plants give oxygen. The food we eat connects us to all four of earth’s systems; air, water, life, and land. Our food crops come from the environment, it’s grown in the soil where water and nutrients are provided, using carbon dioxide from the air and energy from the sun.
2. Everything must go somewhere: Waste doesn’t simply disappear. Waste created from one process will end up in another process. Oxygen is the waste product from plants when they create food during photosynthesis. It’s released back into the air and supports life that breathes oxygen.
3. Nature knows best: Everything in nature has a purpose and can be recycled into another form. Trying to improve or change the natural process always ends up having a negative effect. Adding fertilizers to make crops grow bigger and faster than nature intended can damage soil microbes and pollute waterways.
4. There’s no such thing as a free meal: Every resource we take from the environment has a cost attached. The burning of fossil fuels provides power and transport, but the waste-products increase the temperature of the atmosphere and decrease air quality by adding harmful gases, which can enter the food chain.
We’ll talk more about these laws throughout the various modules of this lesson. With these laws in mind, we can weigh the true cost and benefit of our actions, and make decisions for the present and future generations.
Let’s take a look at ecosystems to find out what they are and how they work.