Final answer:
The water cycle is essential for maintaining water balance, distributing nutrients, and cooling the atmosphere, thus supporting life by regulating the hydrologic cycle and maintaining fertility within ecosystems.
Step-by-step explanation:
The role of the water cycle in sustaining life encompasses several crucial functions, such as maintaining water balance in ecosystems, distributing nutrients, and moderating the climate. Through the water cycle, water enters the atmosphere by evaporation from land and bodies of water, as well as through transpiration from plants, contributing to cooling the atmosphere. It then returns to the Earth's surface in the form of precipitation, replenishing rivers, lakes, and underground aquifers. This continuous movement of water ensures that ecosystems retain their productivity by providing the necessary hydration for plants and animals, distributing nutrients necessary for life, and aiding in soil fertility renewal through decomposition of organic matter.
The atmosphere interacts with the water cycle by providing necessary gases like oxygen for cellular respiration and carbon dioxide for photosynthesis. Ecosystems, such as forests, wetlands, and others, regulate the water resources which are vital for not only direct consumption by organisms but also for agricultural practices that feed populations. In addition, the interaction between biotic and abiotic elements within the hydrologic cycle contributes to the regulation of major element cycles like carbon and nitrogen, which are essential for maintaining the balance of life on Earth.