Changes in grassland ecosystem function due to extreme rainfall events: implications for responses to climate change

Climate change is causing measurable changes in rainfall patterns, and will likely cause increases in extreme rainfall events, with uncertain implications for key processes in ecosystem function and carbon cycling. We examined how variation in rainfall total quantity (Q), the interval between rainfall events (I), and individual event size (SE) affected soil water content (SWC) and three aspects of ecosystem function: leaf photosynthetic carbon gain (ACO2 ), aboveground net primary productivity (ANPP), and soil respiration (JCO2 ). We utilized rainout shelter-covered mesocosms (2.6 m 3 ) containing assemblages of tallgrass prairie grasses and forbs. These were hand watered with 16

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