Pollen rain and pollen representation across a forest-páramo ecotone in northern Ecuador

Modern pollen spectra were studied in forest and páramo vegetation from the Guandera area, northern Ecuador. Pollen representation was estimated by comparing the presence of plant taxa from a recent vegetation survey with the pollen spectra in moss polsters and pollen traps. In total, 73 pollen taxa were identified in the pollen rain. Per relevé, moss polsters and pollen traps contained 21 pollen taxa on average. Redundancy analyses (RDA) of pollen rain spectra against vegetation types yielded similar results for moss polsters and pollen traps. Spectra from forest, páramo, and cultivated field/meadows were well separated along the principal RDA axes, showing the potential to distinguish these vegetation types in pollen records. The modern pollen spectrum from a patch of páramo vegetation located in Andean forest was similar to the spectra of the surrounding forests. Likewise, the pollen spectrum from a forest patch in páramo was similar to spectra from the nearby páramo matrix. The modern pollen spectra from cultivated field/meadows hardly contained pollen taxa typically found in páramo or forest. In both forest and páramo, pollen taxa with wind-dispersed pollination syndromes were overrepresented. Clusia, Ilex, and Weinmannia (only with high percentages) seemed best to infer local presence of forest from pollen records. Puya, Apiaceae, Poaceae (only with high percentages), and Cyperaceae came out as best candidates to infer the presence of páramo vegetation.