Publications by authors named "Yannick Garcin"
Article Synopsis
- The central Congo Basin peatlands store approximately 29 billion tonnes of carbon, with a new model called DigiBog_Congo developed to simulate their carbon accumulation and loss over the last 20,000 years.
- Key factors influencing peat carbon dynamics include water levels at the surface and the slow decay of resistant plant material, with periods of gaining and losing carbon observed between the Late Glacial and early Holocene.
- A significant climatic dry phase starting around 5200 years ago led to extensive peat degradation, where 57% of the carbon stock was released, highlighting the potential impact of climate change on these vital carbon stores in the future.
Article Synopsis
- The forested swamps of the central Congo Basin contain about 30 billion metric tonnes of carbon in peat, but their vulnerability is not well understood.
- Peat accumulation in the region began over 17,500 years ago, with significant decomposition occurring between 7,500 and 2,000 years ago due to a drying climate that lowered the water table.
- Following 2,000 years ago, hydrologic conditions stabilized, leading to a resumption of peat accumulation; this suggests that the carbon stocks may be close to a threshold where climate change could trigger further losses.
Although climate change is considered to have been a large-scale driver of African human evolution, landscape-scale shifts in ecological resources that may have shaped novel hominin adaptations are rarely investigated. We use well-dated, high-resolution, drill-core datasets to understand ecological dynamics associated with a major adaptive transition in the archeological record ~24 km from the coring site. Outcrops preserve evidence of the replacement of Acheulean by Middle Stone Age (MSA) technological, cognitive, and social innovations between 500 and 300 thousand years (ka) ago, contemporaneous with large-scale taxonomic and adaptive turnover in mammal herbivores.
View Article and Find Full Text PDFEarly anthropogenic impact on Western Central African rainforests 2,600 y ago.
Proc Natl Acad Sci U S A
March 2018
A potential human footprint on Western Central African rainforests before the Common Era has become the focus of an ongoing controversy. Between 3,000 y ago and 2,000 y ago, regional pollen sequences indicate a replacement of mature rainforests by a forest-savannah mosaic including pioneer trees. Although some studies suggested an anthropogenic influence on this forest fragmentation, current interpretations based on pollen data attribute the ''rainforest crisis'' to climate change toward a drier, more seasonal climate.
View Article and Find Full Text PDF