Natural ecosystems are communities of living organisms, including plants, animals, and microorganisms, interacting with their physical environment. These ecosystems can be found in various forms, such as forests, wetlands, deserts, and oceans. Each ecosystem has its own unique set of species and environmental conditions that support life. In a natural ecosystem, energy flows through food chains, where producers like plants convert sunlight into energy, and consumers, such as herbivores and carnivores, rely on these producers for food. Decomposers, like fungi and bacteria, break down dead organic matter, returning nutrients to the soil and maintaining the balance of the ecosystem.