Multi-proxy paleolimnological records provide evidence for a shift to a new ecosystem state in the Northern Great Plains, USA

Wetlands in the Prairie Pothole Region of the North American Northern Great Plains perform multiple ecosystem services and are biodiversity hotspots. However, climatological changes can result in sudden shifts in these important ecosystems. For example, marked increases in precipitation in the last few decades have resulted in a widespread shift in wetlands across the Prairie Pothole Region to a new ecohydrological state. We used multi-proxy analyses (diatom community composition and invertebrate stable isotopes) of 210Pb-dated sediment cores from two adjacent, but morphologically and hydrologically different, prairie-pothole wetlands to assess the effects of hydroclimatic variability on these wetland ecosystems. Our results provide evidence that the recent ecohydrological shift in the region’s wetlands is unprecedented over the past ca.178 years. Oxygen stable isotopes in chironomid head capsules provide a record of paleo-hydrology changes. The most recent sediments (i.e., those deposi...

北美北部大平原的草原坑洼地带（Prairie Pothole Region）内的湿地兼具多重生态系统服务功能，同时亦是生物多样性热点区域。然而，气候变动可引发这类重要生态系统的突发性转变。例如，近数十年来降水的显著增加，已促使该区域的湿地大范围转向全新的生态水文状态。我们对两处相邻但形态与水文特征存在差异的草原坑洼湿地的210Pb定年（210Pb-dated）沉积物岩芯开展多代用指标分析，涵盖硅藻群落组成与无脊椎动物稳定同位素分析，以此评估水文气候变异对这类湿地生态系统的影响。我们的研究结果证实，该区域湿地近期发生的生态水文转变，在过去约178年的时间跨度内均无先例可循。摇蚊（chironomid）头部壳体的氧稳定同位素记录了古水文变化历程。最新的沉积物（即那些deposi……）