https://www2.ib.unicamp.br/profs/cjoly/0%20-%20Produ%e7%e3o%20Tematico/4%20-%20Publica%e7%f5es/2010/Alves%20et%20al%202010.pdf

Forest structure and live aboveground biomass variation along an elevational gradient of tropical Atlantic moist forest (Brazil)

Tropical forests account for approximately half of above-ground carbon stored in global vegetation. However, uncertainties in tropical forest carbon stocks remain high because it is costly and laborious to quantify standing carbon stocks. Carbon stocks of tropical forests are determined using allometric relations between tree stem diameter and height and biomass. Previous work has shown that the inclusion of height in biomass allometries, compared to the sole use of diameter, significantly improves biomass estimation accuracy. Here, we evaluate the effect of height measurement error on biomass estimation and we evaluate the accuracy of recently published diameter–height allometries at four areas within the Brazilian Amazon. As no destructive sample of biomass was available at these sites, reference biomass values were based on allometries. We found that the precision of individual tree height measurements ranged from 3 to 20% of total height. This imprecision resulted in a 5–6% uncertainty in biomass when scaled to 1 ha transects. Individual height measurement may be replaced with existing regional and global height allometries. However, we recommend caution when applying these relations. At Tapajos National Forest in the Brazilian state of Para, using the pantropical and regional allometric relations for height resulted in site biomass 21% and 25% less than reference values. At the other three study sites, the pantropical equation resulted in errors of less that 2%, and the regional allometry produced errors of less than 12%. As an alternative to measuring all tree heights or to using regional and pantropical relations, we recommend measuring height for a well-distributed sample of about 100 trees per site. Following this methodology, 95% confidence intervals of transect biomass were constrained to within 4.5% on average when compared to reference values.

/pdf/tree-height-and-tropical-forest-biomass-estimation-35d535nsku.pdf

Tree height and tropical forest biomass estimation

Tropical forest deforestation is a major source of CO2 emissions, yet potential additional emissions through the creation of forest edge areas has been largely overlooked. Here, the authors combine remote sensing and knowledge on spatial processes to estimate carbon loss due to forest fragmentation.

/pdf/long-term-carbon-loss-in-fragmented-neotropical-forests-13kw086q2h.pdf

Long-term carbon loss in fragmented Neotropical forests

O conteudo e apresentado em seis capitulos: Capitulo 1 - Principais iniciativas de restauracao florestal na Mata Atlântica, apresentadas sob a otica da evolucao dos conceitos e dos metodos aplicados; Capitulo 2 - Diagnostico ambiental das areas a serem restauradas visando a definicao de metodologias de restauracao florestal; Capitulo 3 - Monitoramento das areas restauradas como ferramenta para avaliacao da efetividade das acoes de restauracao e para redefinicao metodologica; Capitulo 4 - Quantificacao e monitoramento da biomassa e carbono em plantios de areas restauradas; Capitulo 5 - Metodologia de restauracao para fins de aproveitamento economico (reserva legal e areas agricolas); Capitulo 6 - Descricao das acoes operacionais de restauracao; Referencias bibliograficas; Anexo.

Pacto pela restauração da Mata Atlântica: referencial dos conceitos e ações de restauração florestal

Climate change and high rates of global carbon emissions have focussed attention on the need for high-quality monitoring systems to assess how much carbon is present in terrestrial systems and how these change over time. The choice of system to adopt should be guided by good science. There is a growing body of scientific and technical information on ground-based and remote sensing methods of carbon measurement. The adequacy and comparability of these different systems have not been fully evaluated. A systematic review will compare methods of assessing carbon stocks and carbon stock changes in key land use categories, including, forest land, cropland, grassland, and wetlands, in terrestrial carbon pools that can be accounted for under the Kyoto protocol (above- ground biomass, below-ground biomass, dead wood, litter and soil carbon). Assessing carbon in harvested wood products will not be considered in this review. Developing effective mitigation strategies to reduce carbon emissions and equitable adaptation strategies to cope with increasing global temperatures will rely on robust scientific information that is free from biases imposed by national and commercial interests. A systematic review of the methods used for assessing carbon stocks and carbon stock changes will contribute to the transparent analysis of complex and often contradictory science.

https://www.cifor.org/publications/pdf_files/articles/AMenton1201.pdf

Comparison of methods for measuring and assessing carbon stocks and carbon stock changes in terrestrial carbon pools. How do the accuracy and precision of current methods compare?: a systematic review protocol

The main objective of this paper is to present and discuss the best methods to estimate live above ground biomass in the Atlantic Forest. The methods presented and conclusions are the products of a workshop entitled "Estimation of Biomass and Carbon Stocks: the Case of Atlantic Rain Forest". Aboveground biomass (AGB) in tropical forests is mainly contained in trees. Tree biomass is a function of wood volume, obtained from the diameter and height, architecture and wood density (dry weight per unit volume of fresh wood). It can be quantified by the direct (destructive) or indirect method where the biomass quantification is estimated using mathematical models. The allometric model can be site specific when elaborated to a particular ecosystem or general that can be used in different sites. For the Atlantic Forest, despite the importance of it, there are only two direct measurements of tree biomass, resulting in allometric models specific for this ecosystem. To select one or other of the available models in the literature to estimate AGB it is necessary take into account what is the main question to be answered and the ease with which it is possible to measure the independent variables in the model. Models that present more accurate estimates should be preferred. However, more simple models (those with one independent variable, usually DBH) can be used when the focus is monitoring the variation in carbon storage through the time. Our observations in the Atlantic Forest suggest that pan-tropical relations proposed by Chave et al. (2005) can be confidently used to estimated tree biomass across biomes as long as tree diameter (DBH), height, and wood density are accounted for in the model. In Atlantic Forest, we recommend the quantification of biomass of lianas, bamboo, palms, tree ferns and epiphytes, which are an important component in this ecosystem. This paper is an outcome of the workshop entitled "Estimation of Biomass and Carbon Stocks: the Case of Atlantic Rain Forest", that was conducted at Ubatuba, Sao Paulo, Brazil, between 4 and 8 December 2006 as part of the Brazilian project "Ombrophylus Dense Forest floristic composition, structure and function at the Nucleos Picinguaba and Santa Virginia of the Serra do Mar State Park", BIOTA Gradiente.

/pdf/estimation-of-biomass-and-carbon-stocks-the-case-of-the-3nzcvtjq8w.pdf

Luciana Spinelli Araújo

Papers

Estimation of biomass and carbon stocks: the case of the Atlantic Forest