1. Biodiversity: A sustainable ecosystem boasts a wide variety of species, both plants and animals. This biodiversity ensures a strong food web, resilience to environmental change, and the ability to adapt to new challenges.

2. Nutrient Cycling: Sustainable ecosystems efficiently recycle nutrients within their system. This means they effectively utilize resources, minimize waste, and maintain a balance of essential elements like nitrogen, phosphorus, and carbon.

3. Homeostasis: Sustainable ecosystems are characterized by a natural ability to maintain a stable internal environment despite external fluctuations. This includes regulating temperature, water levels, and the populations of different species. This stability ensures the long-term health and survival of the ecosystem.