Exploring and Understanding Concepts

Example

Explain what an ecosystem is.

1. An ecosystem is all the living things in a place together with their surroundings, working as one connected whole.

Example

Name three interactions in a pond that link living and non-living parts.

1. A non-living part is feeding a living one — the plants capture the sunlight's energy and build food with it.
2. A living thing is reshaping a non-living part — the worms' tunnels open the soil for water and roots.

Example

Name the biotic parts among sunlight, a fern, a rock, a beetle, water, a frog, air, soil, temperature, a tree.

1. Biotic — the living parts of an environment, all its plants, animals and other organisms: the fern, the beetle, the frog, the tree.

Example

Name the abiotic parts, and say how the biotic ones depend on them.

1. Abiotic — the non-living parts, such as sunlight, water, air and soil: sunlight, the rock, water, air, soil, temperature.
2. Every biotic part depends on abiotic ones: the fern on light and soil, the frog on water and warmth.

Example

Give the role of a maple and pond algae.

1. Maple: a producer — it makes its own food, capturing the energy that everything else will pass along. Algae: a producer — it captures sunlight and builds the food on which the pond's eaters all finally depend.

Example

Give the role of a rabbit.

1. Rabbit: a consumer — it cannot build food from sunlight, so it takes its energy by eating other living things.

Example

Give the role of a mushroom and an earthworm.

1. Mushroom: a decomposer — it breaks down dead material and returns its nutrients to the soil for new growth. Earthworm: a decomposer — it feeds on dead material and hands its nutrients back to the soil.

Example

Explain what the arrows carry and where it started.

1. Energy — each arrow points from a living thing to the one that eats it, handing the energy along. From sunlight — the chain's first member captures it; at every link some energy is used for living and movement, so less passes on.

Example

Predict what happens if the algae die.

1. Algae gone: the minnows lose their food and thin out, and then the bass go hungry in turn — the loss climbs the chain link by link.

Example

Predict what happens if the fox is removed from grass → rabbit → fox.

1. Fox gone: with nothing checking them, the rabbits multiply and the grasses are grazed down harder — the change travels down the chain.

Example

Describe how water cycles.

1. Water: the same water is travelling a loop — up as vapour, along as cloud, down as rain — used again and again, never used up.

Example

Describe how carbon in a fallen leaf cycles.

1. Carbon: it returns to the air and the soil as the leaf breaks down, ready for new leaves to build with — the same carbon goes around.

Example

Describe how soil nutrients cycle, and why cycling sustains an ecosystem.

1. Nutrients: what the plants drew from the soil returns to it as they break down, for the next roots to draw again. Sustainability is using what a place provides in ways that keep it healthy far into the future.

Example

Explain what succession is, and the test that tells its two kinds apart.

1. Succession is the slow change of a community over time, as one set of living things gives way to another. The test: is there soil?

Example

Classify as primary or secondary succession: a cooled lava field, a valley scraped by a glacier.

1. Lava: primary — with no soil on the bare rock, life starts from the very beginning, lichens first. Glacier: primary — the scraping left no soil at all.

Example

Classify as primary or secondary succession: a forest after fire, an abandoned farm field.

1. Fire: secondary — the soil and its stored seeds survived, so regrowth starts partway up. Field: secondary — the soil never left, so grasses, shrubs and then trees rebuild the community in turn.

Example

Explain what a limiting factor is.

1. A limiting factor is something in short supply that caps how many living things a place can support.

Example

Name the limiting factor for deer at a shrinking creek and fish in a pond whose smallest living things thin out.

1. Deer: the available water — every deer needs its daily share, and the shrinking creek sets how many shares exist. Fish: the food supply — there are only so many meals to divide.

Example

Name the limiting factor for seabirds on a cliff and owls in a wood.

1. Seabirds: living space — each pair needs its own patch of ledge, and the cliff holds only so many. Owls: shelter — each pair needs a hollow, and the wood grows only so many hollow trees.

Example

Name the harm and the restoring strategy for one crop every year.

1. One crop draws the same nutrients every year until they run low — rotating different crops lets the soil rebuild what each one takes.

Example

Name the harm and the restoring strategy for bare soil by a stream.

1. Rain strips uncovered soil into the stream — cover crops and a rooted strip along the bank hold the ground in place.

Example

Name the harm and the restoring strategy for a drained wetland corner.

1. The wetland had been soaking up storm water and holding nesting cover — letting that corner refill restores the sponge and the shelter together.

Example

Name the harm and the restoring strategy for broad pesticide spray and unrested grazing.

1. The broad spray reached the pollinators along with the pest — spraying narrowly and keeping flowering strips brings the pollinators back. Grazed without rest, the grass cannot regrow its roots — moving the herd between pastures gives each one time to recover.

Summary

• An ecosystem: living things and surroundings as one whole.
• Biotic depends on abiotic.
• Producers make, consumers eat, decomposers return.
• Energy passes along arrows and thins; a break travels up or down.
• Water, carbon and nutrients loop, never used up.
• Primary: no soil; secondary: soil survived.
• Water, food, space, shelter cap numbers.
• Rotate, cover, refill, spray narrowly, rest pastures.