igapó forest

…that add to their fertility—and igapó—i.e., forests flooded annually by black water (in which tannins and humic acid cause the water to appear darker and increase its acidity) that contain slow-growing trees and a few other plants (see also Amazon River).

…of inundated rainforests, várzea and igapó, which constitute about 3 percent of the total Amazon Rainforest. Várzea forests can be found in the silt- and nutrient-rich floodplains of whitewater rivers such as the Madeira and the Amazon, with their ever-changing mosaic of lakes, marshes, sandbars, abandoned channels, and natural levees.…