Water yield depends on the water and carbon trade-off in forest ecosystems
- Resumen
- The cycling of water and carbon between vegetation and the atmosphere is an essential biospheric process with feed-backs to the physical system at various spatial and temporal scales (Claussen 1998; Houghton et al. 1998; Waring and Running 1998; Prentice et al. 2001). A key element of the water/carbon cycles comprises the fixation of atmospheric carbon dioxide (CO2) by photosynthesis and its release by autotrophic and heterotrophic respiration. Net ecosystem exchange (NEE) is the net uptake or release of carbon by terrestrial ecosystems. <br/> The terrestrial water cycle includes the precipitation that enters vegetation from the atmosphere and its recycling to the atmosphere by evapotranspiration (evaporation from wet surfaces and transpiration through the stomata) and runoff to lakes or oceans. The partitioning of incoming precipitation into evapotranspiration and runoff is determined in part by climate (Monteith and Unsworth 1990) and in part by factors such as Leaf Area Index (LAI), canopy structure and hydraulic properties of the vegetation and soil. The carbon and water cycles are tightly coupled because stomatal responses simultaneously control transpiration and CO2 uptake and because microbial decay is strongly constrained by soil moisture conditions, as both too much and too little water reduce microbial activity.
- Autor
- Gracia, Carlos
- Palabras Clave
- Ciclo hidrológico
- Idioma
- Inglés
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