A time-series analysis of airborne photographs and Landsat thematic mapper (TM and ETM+) images and hydrochemical data were used to examine the effects of land-use change from 1930 to 2001 on solute inputs to Lake Calado, a floodplain lake in the central Amazon. Deforestation from slash-and-burn agricultural activities has dramatically decreased the amount of primary growth upland and flooded forests in the basin.

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Major solute concentrations in wet deposition were measured for 115 individual events From October 1988 to June 1990 at Lake Calado, Amazonas, Brazil. A continuous record from July 1989 through June 1990 included 210 events that ranged in size from 0.2 to 85 mm (annual total, 2754 mm). The 95 events chemically analyzed during this period (45% of the total) were evenly distributed over all storm sizes.

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Hydrochemical changes caused by slash-and-bum agricultural practices in a small upland catchment in the central Amazon were measured. Solute concentrations were analyzed in wet deposition, overland flow, shallow throughflow, groundwater and bank seepage in a forested plot (about 5 ha) and an adjacent plot (about 2 ha) which had been deforested in July 1989 and planted to manioc, and in stream water in partially deforested and forested catchments.

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The hydrochemical responses to slash-and-bum agriculture in a small rainforest catchment of the central Amazon were investigated for one year. Disturbances in the partially deforested catchment began in 1987, and during the study a 2-ha plot was cut (July 1989) and burned (October 1989) in preparation for the cultivation of manioc; the partially deforested catchment was approximately 80% deforested at the time of this study.

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