What is nutrient cycling in ecosystems?

Nutrient cycling in ecosystems is the process where nutrients move between living organisms and the physical environment.

In an ecosystem, nutrients like carbon, nitrogen, and phosphorus are essential for the growth and survival of living organisms. These nutrients are continuously recycled through various processes, ensuring that they are available for use by plants, animals, and microorganisms. This recycling helps maintain the balance and health of the ecosystem.

One of the key components of nutrient cycling is the role of decomposers, such as bacteria and fungi. When plants and animals die, decomposers break down their organic matter, releasing nutrients back into the soil. Plants then absorb these nutrients through their roots, using them to grow and produce food. Herbivores eat the plants, and carnivores eat the herbivores, transferring the nutrients through the food chain.

Another important aspect of nutrient cycling is the role of biogeochemical cycles, such as the carbon cycle and the nitrogen cycle. In the carbon cycle, carbon dioxide is absorbed by plants during photosynthesis and converted into organic matter. When plants and animals respire, decompose, or burn, carbon is released back into the atmosphere as carbon dioxide. Similarly, in the nitrogen cycle, nitrogen-fixing bacteria convert atmospheric nitrogen into forms that plants can use. When plants and animals die, decomposers return nitrogen to the soil, where it can be taken up by plants again.

Human activities, such as agriculture, deforestation, and pollution, can disrupt nutrient cycles. For example, excessive use of fertilisers can lead to nutrient runoff into water bodies, causing problems like algal blooms and water pollution. Understanding nutrient cycling helps us manage ecosystems sustainably and minimise our impact on the environment.