U MINH PEATSWAMP FORESTS VIETNAM Tran Triet Vietnam National - - PowerPoint PPT Presentation

U MINH PEATSWAMP FORESTS VIETNAM

Tran Triet Vietnam National University – Ho Chi Minh City Duong Van Ni Can Tho University

Vo Doi U Minh Thuong

Peat swamps

• Hydrology:

– precipitation dominated – permanently waterlogged

• Geomorphological setting:

– raised peats

• Vegetation:

– swamp forest dominated by Melaleuca cajuputi – grasslands

Cross section of U-Minh Thuong Peat dome

Colored water C

• l
• r

e d w a t e r Melaleuca forest Marine sediment layer in 12,000-6,000yBP Pyritic sediment layer 6,000-3,000 yBP

Fresh water sediment <3,000 yBP

฀e at

A B C Rain water Depend on locations, the soil are Non-acid soil (A), Medium acid soil (B), and Severely acid soil (C). Fossil as shell is indicator of marine sediment; Jarosite mottles is indicator of acid soils (Pyritic materials could not see). Water come in to the area is rain water only due high elevation of peat dome.

U Minh Thuong National Park

24,000 ha with 8000 ha core zone One of the two peat swamp forest areas of Vietnam

Peat dome grassland grassland grassland

MIXED SWAMP FOREST

20 40 60 80 100 120 140 160 180 200 1 5 A u g 9 9 1 5 S e p 9 9 1 5 O c t 9 9 1 5 N

• v

9 9 1 5 D e c 9 9 1 5 J a n 1 5 F e b 1 5 M a r 1 5 A p r 1 5 M a y 3 J u n 2 8 J u l 3 A u g 3 S e p 2 5 O c t 3 N

• v

2 8 D e c Elevation in cm (Average mean sea level)

Peat Water table Clay

March – April 2003

Catastrophic fire March-April 2002

Melaleuca regeneration after fire

Buø i Moá p Daá u daà u Traâ m Traø m

B Traø m Buø i Daá u daà u Moá p

C Traø m Daá u daà u

Forest fire

Euodia Alstonia Euginia Melaleuca llex Melaleuca Euodia

Before and after fire

Biodiversity is totally depend on the disturbance of the soil environment. If peat layer was removed (fire) or digging canal to expose the pyritic materials into the air, then oxidation processes will take place and actual acid soils will

• ccurred and biodiversity will be affected by acid water.