Soil physicochemical gradient from headwaters to flooded riparian zones in the Falsino River, Eastern Amazonia 1Postgraduate Program in Environmental Sciences, Federal University of Amapá, Macapá, Amapá, Brazil 2Postgraduate Program in Tropical Biodiversity, Federal University of Amapá, Macapá, Amapá, Brazil 3Civil Engineering Department, Federal University of Amapá, Macapá, Amapá, Brazil 4Institute of Biodiversity and Forests, Federal University of West Para, Santarém, Pará, Brazil...