A Look at Amazon Basin Seasonal Dynamics with the Biophysical ...

RAIN WATER INTERCEPTION BY SELECTIVELY LOGGED RAIN FOREST IN CENTRAL AMAZONIASávio J. F. Ferreira; Flávio J. Luizão; Ricardo G. Dallarosa.INPA - Geociências e Ecologia. E-mail: savio@inpa.gov.brRainfall, internal precipitation, and rain interception were studied over 2 years in selectively logged plots(logged in 1993) and control forest located 80 km North of Manaus, in Central Amazonia. During the firstyear, measurements were continuous and frequent; in the following period, several intensive campaignswere made at selected climatic periods of the year: dry, wet and transitional periods. The internalprecipitation reached 86.9-92.9 % in the selectively logged plots, against 74.2-87.1 % in the untouchedforest. Thus, an increase in the internal precipitation, together with a lower rain water interception, occurredsoon after timber extraction. Also, lower variability of data was observed in the plots subject to selectivelogging, when compared to the control forest. The older managed plots (selectively logged in 1987)presented higher rain interception and lower internal precipitation than plots logged in 1993, showing values(72.0-89.5% of internal precipitation) similar to the untouched forest. It is concluded that moderate selectivelogging changes rain water interception and internal precipitation during the first years after timber extration,but that is recovered when forest structure is recomposed, within a few years, by the secondary regrowth inthe gaps.