Collaborative Research: LTREB- Long-Term Ecosystem Responses to More Extreme Precipitation Patterns and Warming

温度和降雨量极大地影响着草原的结构和功能，使它们特别容易受到预计气候变化的影响。 在中部平原，平均气温预计将上升，降雨模式预计将变得更加多变和极端，大降雨事件的频率将增加，降雨间干旱的时间将延长。 这些变化的生态后果难以预测。该LTREB项目通过支持在一个独特的实验设施（降雨操纵图，RaMP）中长期操纵降雨和温度来解决潜在气候变化的后果。 七年来，我们一直在评估改变降雨模式的影响（更大的降雨事件与更长的降雨间干旱，但总降水量没有变化）在复制的，完整的草地地块。 我们的中心假设是，降雨事件的时间的变化将显着改变时间模式和土壤水分的深度分布，植物，社区和生态系统过程的长期后果。 2003年，我们增加了一个变暖处理，以评估更极端的降雨模式（增加气候变异性）和温度升高（增加气候平均值）的组合的后果。 更多的极端降雨模式和更高的温度的相互作用的影响预计将是复杂的，但对于预测未来气候情景下草地资源和生态系统服务的可持续性至关重要。 该项目将支持本科生和研究生的培训，为科学界提供新的数据，并向公众宣传全球变化研究的重要性。

Temperature and rainfall greatly influence the structure and function of grasslands, making them particularly vulnerable to projected climate changes. In the Central Plains mean temperatures are expected to increase and rainfall patterns are predicted to become more variable and extreme, with an increased frequency of large rainfall events and extended inter-rainfall droughts. The ecological consequences of these changes are difficult to predict. This LTREB project addresses the consequences of potential climate change by supporting the long-term manipulation of rainfall and temperature in a unique experimental facility (the Rainfall Manipulation Plots, RaMPs). For seven years, we have been assessing the impacts of altered rainfall patterns (larger rain events with longer inter-rainfall droughts, but no change in total precipitation amount) in replicated, intact grassland plots. Our central hypothesis is that changes in the timing of rainfall events will significantly alter temporal patterns and depth distributions of soil moisture, with long-term consequences for plant, community and ecosystem processes. In 2003 we added a warming treatment to assess the consequences of a combination of more extreme rainfall patterns (increased climatic variability) and increased temperatures (increased climatic mean). The interactive effects of more extreme rainfall patterns and warmer temperatures are expected to be complex, but will be critical for predicting the sustainability of grassland resources and ecosystem services under future climate scenarios. This LTREB project will support the training of undergraduate and graduate students, provide new data to the scientific community, and inform the general public on the importance of global change research.