6) Peat Swamp Forests Notes

Peat Swamp Forests

  • Peat forms in tropical regions where evapotranspiration exceeds mean precipitation annually.
  • Peatlands accumulate partially decayed organic matter (peat) from plant debris in waterlogged conditions.
  • Greatest peat depths and carbon stores are in peat swamp forests (PSF) at low altitudes in Southeast Asia.
  • PSF started developing around 7000 YBP due to sea level decline and vegetation expansion.

Peat Formation

  • Sediment accumulates at river mouths, forming lagoons.
  • Mangroves establish, increasing sediment deposit.
  • Litter raises an organic layer, leading to peat accumulation.
  • Peat accumulates over time, forming a dome.

Peat Dome Characteristics

  • Dependent on precipitation ('ombrotrophic').
  • Consists of 65% or more of organic matter.
  • Water is very acidic (pH < 4) due to lack of mineral input and leaching of organic compounds.

Vegetation

  • Vegetation changes along peat formation.
  • High species count: 927 species of flowering plants and ferns in Brunei and Sarawak.
  • Common species traits: defence compounds (latex, essential oils, resins, tannins, phenols) due to low nutrient levels.