Water cycle

Human beings have invented hundreds of stock-maintaining mechanisms to make inflows and outflows independent and stable. Reservoirs enable residents and farmers downriver to live without constantly adjusting their lives and work to a river’s varying flow, especially its droughts and floods.

Holistic management focuses on the four ecosystem processes and our potential impact on them. Those processes are: the water cycle, the mineral cycle (which includes the carbon cycle), energy flow, and community dynamics (the complex set of relationships of biology within the ecosystem).

globe. A planetary boundary for freshwater resources needs to secure water flows to regenerate precipitation, support terrestrial ecosystem functioning and services (such as carbon sequestration, biomass growth, food production, and biological diversity), and also ensure the availability of water for aquatic ecosystems.

A working definition of freshwater sustainability that is true to these attributes might be this: in any watershed, ensure that basic water needs are met for all people; preserve ecological infrastructure so as to provide the quantity, quality, and timing of water flows needed to sustain ecosystem services; and where groundwater is tapped, ensure t