Linkages Among Water Vapor Flows, Food Production, and Terrestrial Ecosystem Services

• Main Authors: Johan Rockström, Line Gordon, Carl Folke, Malin Falkenmark, Maria Engwall
• Format: Article
• Language: English
• Published: Resilience Alliance 1999-12-01
• Series: Ecology and Society
• Subjects: catchment management; ecohydrological landscape; evapotranspiration; food production; freshwater management; global freshwater assessment; resilience; terrestrial ecosystem services; trade-offs; water use efficiency; water vapor flows.
• Online Access: http://www.ecologyandsociety.org/vol3/iss2/art5/

Global freshwater assessments have not addressed the linkages among water vapor flows, agricultural food production, and terrestrial ecosystem services. We perform the first bottom-up estimate of continental water vapor flows, subdivided into the major terrestrial biomes, and arrive at a total continental water vapor flow of 70,000 km3/yr (ranging from 56,000 to 84,000 km3/yr). Of this flow, 90% is attributed to forests, including woodlands (40,000 km3/yr), wetlands (1400 km3/yr), grasslands (15,100 km3/yr), and croplands (6800 km3/yr). These terrestrial biomes sustain society with essential welfare-supporting ecosystem services, including food production. By analyzing the freshwater requirements of an increasing demand for food in the year 2025, we discover a critical trade-off between flows of water vapor for food production and for other welfare-supporting ecosystem services. To reduce the risk of unintentional welfare losses, this trade-off must become embedded in intentional ecohydrological landscape management.