Pasture degradation modifies the water and carbon cycles of the Tibetan highlands

The Tibetan Plateau has a significant role with re- gard to atmospheric circulation and the monsoon in partic- ular. Changes between a closed plant cover and open bare soil are one of the striking effects of land use degradation observed with unsustainable range management or climate change, but experiments investigating changes of surface properties and processes together with atmospheric feed- backs are rare and have not been undertaken in the world's two largest alpine ecosystems, the alpine steppe and the Ko- bresia pygmaea pastures of the Tibetan Plateau. We con- nected measurements of micro-lysimeter, chamber, 13 C la- belling, and eddy covariance and combined the observations with land surface and atmospheric models, adapted to the highland conditions. This allowed us to analyse how three degradation stages affect the water and carbon cycle of pas- tures on the landscape scale within the core region of the

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