Question

What specific change in soil chemistry occurs when you use mulch to block light that prevents weeds from growing while still allowing soil respiration?

Accepted Answer

When you put mulch on the ground, you create a layer that stays moist and cool. This mulch blocks sunlight, which stops weed seeds from waking up and growing. As the mulch slowly rots, it breaks down into organic matter, which is just bits of old plants. This stuff eventually mixes into the soil and turns into humus, a dark and crumbly material that acts like a sponge. Humus is special because it holds onto nutrients, like nitrogen, that plants need to grow. Because the mulch allows soil respiration—which is just the soil breathing in oxygen and breathing out carbon dioxide—the tiny living things in the dirt can keep working. These tiny creatures break down the mulch and turn those nutrients into a form that plants can easily drink up through their roots. The main change in soil chemistry is that this process raises the soil&#x27;s cation exchange capacity. Think of this as the soil having more parking spots to hold onto plant food so it does not wash away when it rains. By keeping the soil covered and fed, you make the ground much better at holding onto the building blocks that help your plants grow big and strong.

Home → All Courses → Environmental Science Courses → Climate-Resilient Farming → Flashcard

What specific change in soil chemistry occurs when you use mulch to block light that prevents weeds from growing while still allowing soil respiration?

Community Answers