nutrient cycle

The uptake, use, release, and storage of nutrients by plants and their environments. In temperate ecosystems, far more nutrients are stored in the soil than can be used immediately by plants. The soil then acts as a reservoir for nutrients. In tropical ecosystems, almost all the nutrients are stored in the plants and the soil is impoverished. The living parts of the ecosystem fulfil a number of functions in the nutrient cycle such as regulation of nutrients in outgoing water, the storage of combined nitrogen, and the control of water loss through transpiration.