Full text
| |
| Author(s): |
Larissa Giorgeti Veiga
Total Authors: 1
|
| Document type: | Master's Dissertation |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Instituto de Biologia |
| Defense date: | 2010-08-23 |
| Examining board members: |
Carlos Alfredo Joly;
Flávio Jesus Luizão;
Simone Aparecida Vieira
|
| Advisor: | Carlos Alfredo Joly |
| Abstract | |
Tropical forests store large amounts of carbon in their biomass. Above ground biomass includes living and dead biomass (also known as necromass). Necromass is composed by dead wood (or woody debris) and litter. Woody debris stock is composed by standing dead wood (snags) and fallen dead wood (coarse woody debris) and resultants from the balance between input (via mortality) and output (via decomposition). There are few studies of dead wood in tropical forests and they have mostly focused on dicotyledons. However, Arecaceae, Poaceae Cyatheaceae families are very abundant in tropical forests. This study aimed to quantify biomass and carbon stocks in dead wood components (standing and fallen) along an elevational gradient of Atlantic rain forest of northeastern State of Sao Paulo. Therefore, we studied at 14 permanent plots of 1 ha each established by the project BIOTA / FAPESP - Functional Gradient in physiognomies of "Restinga" at 0 m (sea level), Lowland Ombrophilous Dense Forest (FOD in portuguese) at 100 m altitude, FOD Submontane at 400 m elevation and FOD Montane at 1000 m altitude. For submontane and montane forest sites were established eight (four each one) 1 ha plots, for lowland were established five 1 ha plots and for Restinga was established 1 ha plot. Dead wood biomass tended to increase along the gradient. Coarse woody debris was the component that most contributed to the total stock and represented for 46.8 (Mg / ha) for Restinga; 32.7 (Mg / ha) for FOD Lowlands, 44.4 (Mg / ha) for FOD Submontane and 69.5 (Mg / ha) for FOD Montana. For snags stocks represented for 0.4 (Mg / ha) for Restinga, 0.6 (Mg / ha) for FOD Lowlands, 10.1(Mg / ha) for FOD Submontane and 19.6 (Mg / ha) for FOD Montana. Stocks of Arecaceae was 9.2 (Mg / ha); Cyatheaceae was 7.6 Mg / ha and Poaceae was 18.4 Mg / ha. Carbon stocks were 33.5 Mg / ha for FOD Montana, around 21Mg/ha both FOD Submontane and Restinga, and 14.8 Mg / ha for FOD Lowlands. Densities of standing dead wood and fallen dead wood decreased according to advance in decomposition. For snags and for coarse woody debris the values ranged from 0.1 to 0.4 (g/cm³) for dicotyledons. For Euterpe edulis (Mart.) values ranged from 0.3 to 0.4 (g/cm3). For Cyathea sp. ranged from 0.18 to 0.28 (g/cm³) and for bamboo density was 0,09 (g/cm3). The families Arecaceae, Poaceae and Cyatheaceae, contributed little to the total stock of dead wood. The dead biomass responded, on average, by 18% of the total biomass above ground, and must be considered an important reservoir of biomass and carbon in these ecosystems. As the output of this carbon component is highly dependent on humidity and temperature, this can be a particularly sensitive compartment, anticipated changes to the climate and therefore must be better evaluated in future studies. This study is included in Biota Gradiente Funcional Project (FAPESP 03/12595-7). (AU) | |