Paleoclimate and paleoecology of the northern lowland Neotropics, Phase I and II: Limnological survey of modern aquatic environments and paleoclimate reconstructions from fossil species assemblages recovered by the Lago Petén Itzá Scientific Drilling Proj

我们提议在尤卡坦半岛进行第二次实地考察(2007年2月至3月)，以完成我们根据2005/2006年第一次实地考察期间收集的生态、水生地球化学和湖泊学数据开始建立的训练集。这是必要的，因为我们需要一个统计上合理的数据库，由至少50个湖泊的数据组成。这将使我们能够(1)恢复对Lago Petén Itzá科学钻探项目(PISDP)的第一阶段的贡献，这是对现代水环境的湖泊学调查，以及(2)将传递函数和干扰统计应用于介形虫和摇蚊的物种组合(合作伙伴正在对硅藻和枝角类进行分析)、钙质介形虫阀门的稳定氧和碳同位素以及水生地球化学数据，以便为解释2005年在Petén Itz湖进行的湖泊调查期间从短岩心中恢复的化石物种组合建立培训集。我们还建议开始第二阶段，即分析和解释化石物种组合，从2006年2月至3月从Petén Itzá湖采集的长岩芯的第一组样本开始。

We propose a second field campaign of a limnological survey (February-March 2007) across the Peninsula Yucatán in order to complete the training set that we started to build from ecological, aquatic geochemical and limnological data collected during the first field campaign in 2005/2006. This is necessary because we need a statistically sound database, consisting of data from a minimum of 50 lakes. This will allow to (1) resume Phase I of our contribution to the Lago Petén Itzá Scientific Drilling Project (PISDP), the limnological survey of modern aquatic environments, and (2) to apply transfer functions and interference statistics to species assemblages of ostracodes and chironomids (diatoms and cladocerans are being analyzed by cooperation partners), stable oxygen and carbon isotopes of calcareous ostracode valves as well as aquatic geochemical data in order to build training sets for the interpretation of fossil species assemblages recovered from short cores taken during the limnological survey in Lake Petén Itzá in 2005. We also propose to start Phase II, the analysis and interpretation of fossil species assemblages with a first set of samples from long cores recovered from Lake Petén Itzá in February-March 2006.