Necromass Carbon Stock in a Secondary Atlantic Forest Fragment in Brazil

Abstract

Necromass has a relevant role to play in the carbon stock of forest ecosystems, especially with the increase of tree mortality due to climate change. Despite this importance, its quantification is often neglected in tropical forests. The objective of this study was to quantify the carbon storage in a secondary Atlantic Forest fragment in Viçosa, Minas Gerais, Brazil. Coarse Woody Debris (CWD), standing dead trees (snags), and litter were quantified in twenty 10 m x 50 m plots randomly positioned throughout the forest area (simple random sampling). Data were collected during 2015, from July to December. The CWD and snags volumes were determined by the Smalian method and by allometric equations, respectively. The necromass of these components was estimated by multiplying the volume by the apparent density at each decomposition classes. The litter necromass was estimated by the proportionality method and the average of the extrapolated estimates per hectare. The carbon stock of the three components was quantified by multiplying the necromass and the carbon wood content. The total volume of dead wood, including CWD and snag, was 23.6 ± 0.9 m3 ha−1, being produced mainly by the competition for resources, senescence, and anthropic and climatic disturbances. The total necromass was 16.3 ± 0.4 Mg ha−1. The total carbon stock in necromass was 7.3 ± 0.2 MgC ha−1. The CWD, snag and litter stocked 3.0 ± 0.1, 1.8 ± 0.1, and 2.5 ± 0.1 MgC ha−1, respectively. These results demonstrate that although necromass has a lower carbon stock compared to biomass, neglecting its quantification may lead to underestimation of the carbon balance of forest ecosystems and their potential to mitigate climate change.

Physical and chemical properties of Coarse Woody Debris submitted to the natural process of decomposition in a Secondary Atlantic Forest Fragment in Brazil

“…This reduction in density can be explained by the weight loss due to wood-decomposing microorganisms’ action 61 . Previous studies have also found this pattern of data behavior for CWDs density 37 – 39 , 50 .…”

“…The arithmetic means of the diameters measured at the ends of the residues was calculated to separate the material into diameters classes with an amplitude of 5 cm. The CWDs found into these plots were divided into 4 classes according to their stage of decomposition 48 – 50 : (i) Materials that have just fallen to the ground with leaves and bark intact; (ii) Materials similar to those of class “i”, but with the bark showing rotting or peeling; (iii) Materials with a high stage of decomposition and showing some resistance to being broken; (iv) Materials that are rotten, friable and without resistance to being broken.…”

A Necromassa Nos Ecossistemas Florestais: Uma Revisão Sobre Os Métodos E Iniciativas De Quantificação Do Estoque De Carbono

“…Assim, o conhecimento dos vários métodos disponíveis para a quantifi cação da necromassa é fundamental para tirar conclusões válidas e para desenvolver estratégias para o manejo destes resíduos fl orestais (Clark et al, 2017). Além disso, o conhecimento de iniciativas que contabilizam o estoque de carbono na necromassa em seus relatórios ou pesquisas científi cas podem contribuir para a valorização dos ecossistemas fl orestais como sumidouro de carbono (Villanova et al, 2019). Desta forma, o objetivo deste boletim técnico foi realizar uma revisão de literatura a respeito dos métodos e iniciativas de quantifi cação do estoque de carbono na necromassa, levando em consideração as principais limitações de cada método e o potencial existente frente à incorporação deste parâmetro às métricas de análise dos ecossistemas fl orestais como sumidouro de carbono.…”

Can fallen trees enhance aboveground biomass estimation? A proposal for the Brazilian Atlantic Forest

“…In the Atlantic Forest, studies on necromass are in their initial stages. Particularly on the thick necromass compartments (CWD and SDT), there are even fewer studies (Sanquetta, Corte, Pinto, & Melo, 2014;Deus, Bonete, Figueiredo, Dias, & Bonete, 2018;Moreira, Gregoire, & Do Couto, 2019;Fonsêca, Meunier, & Silva, 2019;Villanova et al, 2019).…”