Wetland extent, vegetation cover, and inundation state were mapped for the first time at moderately high (100 m) resolution for the entire lowland Amazon basin, using mosaics of Japanese Earth Resources Satellite (JERS-1) imagery acquired during low-and high-water seasons in 1995-1996. A wetlands mask was created by segmentation of the mosaics and clustering of the resulting polygons; a rules set was then applied to classify wetland areas into five land cover classes and two flooding classes using dual-season backscattering values. The mapped wetland area of 8.4×10 5 km 2 is equivalent to 14 % of the total basin area (5.83×10 6 km 2 ) and 17 % of the lowland basin (5.06×10 6 km 2 ). During high-water season, open water surfaces accounted for 9 % of the wetland area, woody vegetation 77 %, and aquatic macrophytes 14 %. Producer's accuracy as assessed using high-resolution digital videography was better than 85 % for wetland extent. The mapped flooding extent is representative of average highand low-flood conditions for latitudes north of 6°S; flooding conditions were less well captured for the southern part of the basin. Global data sets derived from lowerresolution optical sensors capture less than 25 % of the wetland area mapped here.
We applied spatial data analysis and geostatistical procedures to pH, total suspended sediment and chlorophyll-a concentration data gathered on an Amazon floodplain lake. Variographic analysis and ordinary kriging interpolation were used to identify and describe spatiotemporal patterns of variability in these parameters, which are relevant to understand the dynamics of water circulation on the floodplain lake. In spite of the complexity of the processes underlying the spatiotemporal patterns, this approach demonstrated that the heterogeneity in the seasonal water composition is forced not only by the Amazon River flood pulse, but also by the lake bottom topography and the wind intensity.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.