Publications by authors named "Ian T Lawson"
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.
To date there have only been two studies using testate amoebae as palaeoecological indicators in tropical peatlands. Here we present a new ∼500-year testate amoeba record from San Jorge, a domed peatland in Peruvian Amazonia, which has a well-constrained vegetation history based on pollen analysis. We observe a major shift from Hyalosphenia subflava to Cryptodifflugia oviformis-dominated communities at ∼50 cm depth (c.
View Article and Find Full Text PDFPeatlands are carbon-rich ecosystems that cover just three per cent of Earth's land surface, but store one-third of soil carbon. Peat soils are formed by the build-up of partially decomposed organic matter under waterlogged anoxic conditions. Most peat is found in cool climatic regions where unimpeded decomposition is slower, but deposits are also found under some tropical swamp forests.
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