Pollen density in sediment cores from St. Louis River and Lake Superior, Minn...

Pollen density is measured per dry weight of sediment.TRSHR - Trees & shrubs groupUPHRB - Upland herbs groupWETEM - Wetland emergents groupAQUAT - Aquatics groupPTERI -...花粉密度以沉积物干重计。TRSHR - 树木与灌木类群（Trees & shrubs group）；UPHRB - 山地草本类群（Upland herbs group）；WETEM - 湿地挺水植物类群（Wetland emergents group）；AQUAT - 水生类群（Aquatics group）；PTERI -……