Wetlands

Both indigenous and post-Conquest peoples living in the Amazon have had names for specific types of wetlands. Water types (whitewater, blackwater and clearwater) and vegetation are usually the two main characteristics used in these local classifications. Only with the general availability of satellite imagery, especially after about 2000 when Landsat and other imagery became widely available and cheaper, did it become possible for academics to better understand the extent of flooding in the Amazon Basin and distinguish major wetland types. This led to a considerable increase in the percentage of the Amazon recognized as wetlands, from 2-4% in the 1970s to as high as 12-14% as of 2014, depending on exactly how a wetland is defined. In 2010 John Melack and Laura Hess presented the first modern and nearly Amazon-wide wetland classification, less most of the Andes, the estuary and the Tocantins Basin. This classification leans heavily on vegetation types as proxies for distinct wetlands. The Estuary and Tocantins Basin have now been included in the classification. The Melack-Hess classification, which is in a Geographical Information System (GIS), can fairly easily be adapted to the Ramsar Convention on Wetlands (RCW) categories.

Another broad academic wetland classification was developed by the Max Planck Institute’s Tropical Ecology Workgroup (headed by Wolfgang Junk). It is based on climatic, hydrologic, chemical and biological criteria (especially vascular plants), but structures its top hierarchical level on flooding regimes. The classification hierarchy starts with two classes: 1) wetlands with relatively stable water levels; and 2) wetlands with oscillating water levels. Notably different than the RCW classification, the Max Planck classification is structured primarily by water levels, leaving floodplains as a major sub-class. RCW does not consider floodplain as a major wetland class; rather, various types of wetlands are identified on the floodplains. Finally, the Max Planck team classification does not explicitly consider the open areas of rivers and streams as a wetland type, thus resulting in somewhat disconnected wetlands within the classification. RCW considers rivers and streams to be a wetland type and ecologically this is extremely useful, particularly in showing the connectivity of wetlands and even fish migrations.

The classifications mentioned above should be considered first steps for developing regulatory classifications on which environmental policy can be based. Given the history of wetland regulation in the Amazon Basin, or lack thereof, it would probably be wise to begin with relatively simple and obvious regulatory wetland classifications. The main challenge will be application at various administrative scales: international, national, state/departmental, municipal, indigenous and/or other levels.