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

Effect of selective logging on biomass and tree growth in Tapajos National ForestC.A.de Sousa 1 , A.M.Figueira 2 , M.Goulden 3 , H.da Rocha 4 , M.Menton 3 , S. Miller 3 , R.Juarez 4 ,A. Maia 51Iniciação Científica CNPq/LBA2Desenvolvimento Regional RHAE/LBA3University of California, Irvine4Universidade de S. Paulo5 Universidade Federal do ParaAuthor address: Rua 24 de Outubro, 3707. Caixa Postal 31.CEP: 68040010. Santarem – Para– BrazilEmail: albert_bio@hotmail.comSelective logging creates a mosaic of gaps in a forest and alters species composition, forestmicroclimate, and water and carbon cycling. We are using biometry and dendrometry todetermine the biomass and tree growth before, during, and after selective logging in a tropicalforest. We inventoried a 600 by 300-m block in an undisturbed stand in the Floresta Nacionaldo Tapajós, south of Santarém, PA during April 2000. The block contained 1036 trees withDBH > 35 cm and 784 trees with DBH between 10 and 35 cm. All of the trees wereidentified to species and tagged, and a subset of 400 trees were equipped with stainless steeldendrometers. The stand was subsequently logged in September 2001, resulting in a mosaicof gaps and relatively intact forest. After logging, we installed an additional 400dendrometers near gaps created by the logging. The dendrometers were measured at 6 weekintervals, and we plan to continue these measurements for several more years. Thedendrometer observations prior to the logging are being used to determine the seasonal patternof stem increment in the absence of disturbance. The dendrometer observations following thelogging are being used to gauge the regrowth of the forest, and to determine the relativeimpact of logging on tree growth in patches of intact forest vs gaps vs the edges of gaps.Keywords: biomass, carbon, primary tropical forest, selective logging