Biomass and Necromass in Three Undisturbed Forests in the Brazilian Amazon
Michael
William
Palace, University of New Hampshire, palace@kaos.sr.unh.edu
(Presenting)
Michael
M.
Keller, University of New Hampshire,USDA Forest Service, International Institute of Tropical Forestry, michael.keller@unh.edu
Gregory
Paul
Asner, Department of Global Ecology, Carnegie Institution of Washington, Stanford University, gpa@stanford.edu
José
Natalino Macedo
Silva, EMBRAPA-Amazonia Oriental, natalino@cpatu.embrapa.br
Necromass (Coarse Woody Debris [CWD]) is important component of the carbon cycle in tropical forests. The relationship between necromass and biomass may provide interesting insight into the functioning of a forest. Forests with the same biomass but differing necromass pools might have experienced different disturbance and mortality events or have different decomposition histories. This study examined three undisturbed Amazonian forests, Cauaxi, Para (3.75° S, 48.37° W), Tapajos National Forest, Para, Brazil (3.08° S, 54.94° W) and Juruena, Mato Grosso, Brazil (10.48° S, 58.47° W). We compared biomass, DBH distributions, standing necromass, fallen necromass and CWD decay class distributions. Relationships between each of these parameters were used to compare carbon cycling across the sites. At Tapajós, the average mass (+/- S.E.) of fallen CWD was 50.7 (1.1) Mg ha-1 for duplicate sites. The average mass of fallen CWD at Juruena was 44.4 (16.3)Mg ha-1 for duplicate sites. At Cauaxi, fallen CWD mass average was 55.2 (4.7) Mg ha-1. Small (> 2 cm and < 5 cm dia ) and medium sized material (> 5 cm and < 10 cm dia) accounted for 8-18% of the total fallen CWD mass. Standing dead average mass was 33.5 (4.0) Mg ha-1 for duplicate sites at Tapajos. At Juruena, the average mass of standing dead was 24.8 (6.5) Mg ha-1 for duplicate sites. Standing dead was not measured at Cauaxi. The biomass estimate for > 10 cm DBH for Juruena was 313 Mg ha-1. Cauaxi biomass for trees > 20 cm DBH was 249 Mg ha-1. Tapajos biomass estimate for trees > 15 cm was 224 Mg ha-1. Finally, estimates from an automated crown detection algorithm were used to compare disturbances across each of these sites.
Submetido por Michael William Palace em 18-MAR-2004
Tema Científico do LBA: CD (Armazenamento e Trocas de Carbono)