This document summarizes a case study on watershed ecosystem investigation for climate change adaptation in the Sirindhorn International Environmental Park in Thailand. It analyzes two watersheds - Bang Tra Noi and Huay Sai - examining land use, soil, forest, water resources, wildlife, and socioeconomics from 1954 to 2015. Key findings include moderate soil erosion, mixed deciduous forests covering 25-34% of the watersheds, higher water quality parameters during wet versus dry seasons, and need for more efficient water use, forest protection, and community participation in management. The study provides guidelines for sustainable integrated watershed management.

1. Watershed Ecosystem Investigation
for Climate Change Adaptation
: Case Study for the Sirindhorn
International Environmental Park
Dr.Sonjai Havanond

2. Climate Change
Relation, Lingkage and Variation
Watershed Ecosystem
Adaptive Watershed Management
Researchers, Land Managers, Communities &
Other stakeholders
Soil, Water, Forest,
Wildlife, Socio-economics

3. 1954 1967
1976 1993
Bang Tra Noi and Huay Sai Watersheds

4. Bang Tra Noi Watershed Condition in 1982

5. Huai Sai Head Watershed area in 1916

6. Reforestation area from Huai Sai down to
coastal area ff Sirindhorn International Park

7. Mangrove Rehabilitation and Coastal Protection
in SIEP

8. Mangrove Learning Classroom in SIEP

9. http://www.mygreengardens.com
Drip Irrigation System

10. http://www.dripirrigationsystemguys.com/vt/
Drip Irrigation System

12. Artificial Reef : Laboratory test
Wave Basin
Wave Flume
Physical Model test in Laboratory Wave Basin

14. Before
After
14 February 2005
11 January 2008

15. ARTICIFIAL REEF

17. 17
Forest resource sampling plots
Pasture and Livestock
Pasture and Scrub forest
Paddy field
Mixed deciduous forest
Horticulture
Agronomy
Swamp area
Government office
Communication station
Forest plantation
Village
Others
Mining
Reservoir
Water body
Orchard
Symbol
Landuse Map 2014
17

18. Huay Sai Royal
Development Study
Center(1983)
20061997
Wet
Forest
Check dam and
ponds
Vetiver grass
Forest plantation 3
types for 4 benefits

19. Coastal Landscapes Management
Topography Mosaic
Watershed
area
Agriculture area +
Community
From Huai Sai watershed area down to
coastal area of The Sirindhorn International
Environmental Park
Coastal Zone
Brackish
area
Low land
River

20. Objectives
1. Gathering watershed resources information:- land use,
soil, forest, water, wildlife, and socio-economic within 2
watershed which cover SIEP area
2. Study integrated linkage relationship of 2 watershed
ecosystem and adjacent area
3. Formulation guideline for sustainable integrated
watershed management with people participation
Study
watersheds
- SIEP
- Adjacent
SIEP

21. Land use change of the year 2009 and 2015
for Bangtranoi (BTN) and Huaisai (HS) Watershed
Land use type
Bangtranoi (sq.km.) Huaisai (sq.km.)
2009 2015 2009 2015
Agriculture 19.50 17.61
(27.47 %)
7.06 4.66
(23.89 %)
Forest 16.54 16.07
(25.07 %)
6.41 6.64
(34.03 %)
Communities 17.49 21.55
(33.62 %)
3.86 6.04
(30.96 %)
Water Bodies 1.32 2.94
(4.59 %)
0.71 0.99
(5.07 %)
Miscellaneous 9.25 5.93
(9.25 %)
1.47 1.18
(6.05 %)
Total 64.10 64.10 19.51 19.51
Land use type

22. Soil sampling location
1. Slope complex ; Sc
2. Nhong Kae ; Nk
3. Hup Ka Pong ; Hg
4. Chonburi ; Cb
5. Samutprakavn ; Sm
6. Watana ; Wa

23. • Soil texture was classified as sandy loam
• Soil infiltration showed very high rate for BTN
and HS with an average of 31.52 and 30.91
cm./hr. respectively
• Soil fertility focus on N, P, K and Ca are under
low rate while Mg showed high rate
• Soil erosion was classified as moderate rate
for BTN (20.29 tons/ha./yr.) whereas low rate
was defined for HS (7.18 tons/ha./yr.)

24. • Remain forests covered were approximately 25
and 34% for BTN and HS WS respectively
• Forest types were comprise of mixed deciduous
with dry dipterocarp forest, reforestation, beach,
and mangrove forest
• Approximately 150 tree species were discovered

25. 








25
(Whole) Water
sample sites

26. Water yield/Streamflow
(MCM)
BTN % of total
flow
HS % of total
flow
% of rainfall 9.69 2.63
Wet flow 16.35 14.32
Dry flow 8.60 (88.75) 2.33 (88.59)
% wet flow/dry flow 1.09 (11.25) 0.30 (11.41)
BTN HS
Water supply (MCM) 9.69 2.63
Water demand (MCM) 11.06 5.95
Number of population
(person)
8,592 4,620
(an average of water for domestic use 1,288 m3/person/year)
Water supply
Water requirement

27. • Most of water quality parameters in wet season
(August 2015) of BTN and HS WS was higher than dry
season (April 2015)
• For BTN, BOD, DO, TDS, Nitrate, Phosphate, TCB, and FCB in wet
season were higher than dry season
• Both BTN and HS WS shown higher TCB (415 and 170 MPN/100
ml) and FCB (182.5 and 130 MPN/100 ml.) respectively in wet
season may cause from livestock activities along the stream
channel and organism activities in water
• Both BTN and HS WS water quality were in surface
water quality standard class 3

28. 1) For water shortage, concern agencies should motivated people
in both WS to know how to use water more efficiency and
conservation of water both in term of amount and quality
2) For forest resource, concern government agencies must strictly
on land use change and maintain remaining forest. Additionally,
increase forest area is strongly recommend
3) For low participation of all activities, relevant organism should
encourage the community for more effective participation for all
activities