LiDAR-based reference aboveground biomass maps for tropical forests of South Asia and Central Africa.
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ABSTRACT:
SUBMITTER: Rodda SR
PROVIDER: S-EPMC10995191 | biostudies-literature | 2024 Apr
REPOSITORIES: biostudies-literature
Publications
LiDAR-based reference aboveground biomass maps for tropical forests of South Asia and Central Africa.
Rodda Suraj Reddy SR Fararoda Rakesh R Gopalakrishnan Rajashekar R Jha Nidhi N Réjou-Méchain Maxime M Couteron Pierre P Barbier Nicolas N Alfonso Alonso A Bako Ousmane O Bassama Patrick P Behera Debabrata D Bissiengou Pulcherie P Biyiha Hervé H Brockelman Warren Y WY Chanthorn Wirong W Chauhan Prakash P Dadhwal Vinay Kumar VK Dauby Gilles G Deblauwe Vincent V Dongmo Narcis N Droissart Vincent V Jeyakumar Selvaraj S Jha Chandra Shekar CS Kandem Narcisse G NG Katembo John J Kougue Ronald R Leblanc Hugo H Lewis Simon S Libalah Moses M Manikandan Maya M Martin-Ducup Olivier O Mbock Germain G Memiaghe Hervé H Mofack Gislain G Mutyala Praveen P Narayanan Ayyappan A Nathalang Anuttara A Ndjock Gilbert Oum GO Ngoula Fernandez F Nidamanuri Rama Rao RR Pélissier Raphaël R Saatchi Sassan S Sagang Le Bienfaiteur LB Salla Patrick P Simo-Droissart Murielle M Smith Thomas B TB Sonké Bonaventure B Stevart Tariq T Tjomb Danièle D Zebaze Donatien D Zemagho Lise L Ploton Pierre P
Scientific data 20240404 1
Accurate mapping and monitoring of tropical forests aboveground biomass (AGB) is crucial to design effective carbon emission reduction strategies and improving our understanding of Earth's carbon cycle. However, existing large-scale maps of tropical forest AGB generated through combinations of Earth Observation (EO) and forest inventory data show markedly divergent estimates, even after accounting for reported uncertainties. To address this, a network of high-quality reference data is needed to ...[more]
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Project description:BackgroundLong-term studies of community and population dynamics indicate that abrupt disturbances often catalyse changes in vegetation and carbon stocks. These disturbances include the opening of clearings, rainfall seasonality, and drought, as well as fire and direct human disturbance. Such events may be super-imposed on longer-term trends in disturbance, such as those associated with climate change (heating, drying), as well as resources. Intact neotropical forests have recently experienced increased drought frequency and fire occurrence, on top of pervasive increases in atmospheric CO2 concentrations, but we lack long-term records of responses to such changes especially in the critical transitional areas at the interface of forest and savanna biomes. Here, we present results from 20 years monitoring a valley forest (moist tropical forest outlier) in central Brazil. The forest has experienced multiple drought events and includes plots which have and which have not experienced fire. We focus on how forest structure (stem density and aboveground biomass carbon) and dynamics (stem and biomass mortality and recruitment) have responded to these disturbance regimes.ResultsOverall, the biomass carbon stock increased due to the growth of the trees already present in the forest, without any increase in the overall number of tree stems. Over time, both recruitment and especially mortality of trees tended to increase, and periods of prolonged drought in particular resulted in increased mortality rates of larger trees. This increased mortality was in turn responsible for a decline in aboveground carbon toward the end of the monitoring period.ConclusionProlonged droughts influence the mortality of large trees, leading to a decline in aboveground carbon stocks. Here, and in other neotropical forests, recent droughts are capable of shutting down and reversing biomass carbon sinks. These new results add to evidence that anthropogenic climate changes are already adversely impacting tropical forests.
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