| Ecoregion: Northern Vietnam lowland rain forests | |
|---|---|
 Lake Song Muc inBen En National Park | |
 Ecoregion territory (in purple) | |
| Ecology | |
| Realm | Indomalayan |
| Biome | Tropical and subtropical moist broadleaf forests |
| Geography | |
| Area | 22,532 km2 (8,700 sq mi) |
| Country | |
| Coordinates | 19°N105°E / 19°N 105°E /19; 105 |
TheNorthern Vietnam lowland rain forestsecoregion (WWF ID: IM0141) covers the central-eastern coast ofVietnam from theRed River delta in the north toTam Kỳ in the center of the country and neighboring adjacent parts ofLaos. The region is one of thewet evergreen forests, with rain over 50 mm in every month. The forests have been highly degraded by human use, and the high levels of biodiversity have been pushed back into relatively small protected areas likePu Mat National Park.[1][2][3]
The region is about 380 km from north to south, and about 50 km wide on average. It is bounded by the coast on the east, and theNorthern Annamites rain forests to the west. The geological base features extensive limestone ('karst') mountains and valleys. Elevations range from sea level to 1,000 meters, with an average of 88 meters.[3] The primary wet evergreen forest has mostly been cleared in the past by humans; by one estimate only 10% of the original remains.[1]
The climate of the ecoregion isTropical rainforest climate (Köppen climate classification (Af)). This climate is characterized as hot, humid, and having at least 60 mm of precipitation every month.[4][5] Annual rainfall increases towards the south, averaging 1,500 mm in the north nearHanoi, and reaching 3,000 mm in the south nearHuế. The wet seasons are typically September to January.
The original wet evergreen forest has been mostly broken up by human agriculture and use, and now exists in scattered patches.[1] Over the ecoregion as a whole, only 28% is currently under forest cover; 31% is under agricultural cultivation.[3] The primary forest that exists exhibits a three-tiered canopy rising 25–35 meters, but emergents can grow up to 45 meters. The highest tier is dominated by trees of theHopea genus,Castanopsis hystrix andMadhuca pasquieri. A common sub-canopy tree is the Taraw palm (Livistona saribus), used for thatching on huts.
The treeLeoheo domatiophorus is endemic to the ecoregion. It is native toHuế,Quang Tri andQuang Nam provinces, where it typically grows at the edges of primary and secondary forests.[6]
The ecoregion supports some rare animals, including the largest viable population of the critically endangeredNorthern white-cheeked gibbon (living inPu Mat National Park), the critically endangeredRed-shanked douc, and populations ofGray langurs (a genus ofOld world monkey).[1]
Officially protected areas in the ecoregion include:
Media related toNorthern Vietnam Lowland Rainforests Ecoregion at Wikimedia Commons