Subject(s): Ecosystem -- Waterneeds -- Water functions in the life-support system -- Water -The bloodstream of the biosphere : Invisible water, water-plant interaction, Human landscape interventions -- Water availability-Expanding the perspective : Conceptual shifts to incorporate water for ecosystem, Introducing soil water into the water balance equation, water resource estimates -- Human water requirements : Household and industrial water needs, Water use and consumptive water use, Current green water requirements for food production, Generic human water requirement, Additional water requirements to feed humanity by 2050 -- Incorporating water for ecosystem service : Expanding the paradigm, Water flows to sustain food production, green water flows are sustaining major biomes, Committed and uncommitted water flows, Blue water bias in unwarranted -- Regional differences :Green water perspective, Blue water perspective, Combined perspective -- Closing upon the vulnerable savanna zone -- Vulnerability of the savann zone : dryland - cradle of mankind, Savannaagro-ecosystem, Hydroclimatic challenges and opportunities, Droughts and dry spells -- Water perspectives on feeding humanity : More crop per drop, Irrigation expansion and food scarcity, Potential to increase rainfed production Green water losses -- Closing the yield gap on the Savanna -The real world perspective : Changing farmers risk perception, Water sources for dry spell mitigation, Upstream-downstream perspective -- Socio-ecohydrological balancing -- Finding the balance between water for human and for nature -- Towards hydrosolidarity through integrated land/water/ecosystem management