The Sumatran freshwater swamp forests are scattered, disjunct patches of swamp forest on the low alluvial floodplains of eastern Sumatra, Indonesia, within the Indomalayan realm. These forests grow where meandering rivers periodically flood the land, sometimes for over four months at a time; because the flowing water flushes out biomass and deposits fresh alluvial soil, the substrate stays more fertile and less acidic than the neighboring peat swamps, supporting a diverse canopy of tree genera such as Alstonia, Campnosperma, Mallotus, Dillenia, Dyera, Erythrina, and Eugenia. The climate is tropical rainforest (Köppen Af) — hot, humid, and wet enough to receive at least 60 mm of rain in every month — across terrain that rises no higher than about 63 meters. Several sectors still shelter Asian elephants, Sumatran tigers, and the Malayan tapir, and the ecoregion's flagship is the flat-headed cat, a small fishing cat with webbed feet adapted to hunting in wetlands, though only a small fraction of the habitat is formally protected as logging and conversion to agriculture continue. For gardeners, the native flora includes the coral trees (Erythrina) and Dillenia, both grown ornamentally in suitably warm, wet climates.
Marker placed inside the RESOLVE 2017 polygon at 2.4°N, 100.0°E.
Climate snapshot for this ecoregion
°C
°F
Current zone range (2011–2040)
13b
Plotwright
CHELSA-derived typical winter month at this ecoregion's bbox grid.
Projected (2041–2070)
13b
Plotwright
Where the CHELSA models say the typical winter month is heading.
Average warming this ecoregion is on track for: +2.7°F by mid-century. SSP3-7.0 (current trajectory) · CHELSA v2.1 bio06 sampled across 10 of 10 points within this ecoregion's bounding box.
At a glance
Dominant biome
Tropical & Subtropical Moist Broadleaf Forests
Realm
Indomalayan
Approximate area
6,985 sq mi
Conservation tier
Nature Could Recover (Dinerstein NNH 3)
About the tropical & subtropical moist broadleaf forests biome
Warm, wet, highly productive forests — including tropical rainforests — with closed canopies, near year-round growing seasons, and the richest terrestrial biodiversity on Earth. Low seasonality and high rainfall sustain dense, layered vegetation from canopy to forest floor.
Catalog plants suited to this ecoregion
No catalog plants intersect this ecoregion's zone range. As the catalog grows to cover this region's climate band, suggestions will surface here.
Collections for this ecoregion
No curated collection's plants all fit this ecoregion's zone range. We surface a collection only when every member would grow here — partial fits get filtered out rather than mislead. As the catalog and the curated set both grow, this section will fill in.
Related ecoregions
Other tropical & subtropical moist broadleaf forests ecoregions to explore: