Research in Tropical Ecohydrology - CTAHR Website in Tropical Ecohydrology ... Hill evergreen : 0.60 . ... Wet-Canopy Evaporation vs Transpiration . 0.00 0.05 0.10 0.15 0.20 0.25

Research in Tropical Ecohydrology

Thomas Giambelluca Geography Department

University of Hawai‘i at Mānoa

Guest Lecture

NREM 680: Ecosystem Ecology Seminar 14 February 2012

Photo: Christopher McLeod

My Research Focus: Ecohydrology and Climatology

• Influence of land-cover change on hydrologic and climatic

processes (China, Thailand, Vietnam, Cambodia, Brazil) • Forest evapotranspiration and cloud-water interception in

Hawai‘i (Maui, Big Island) • Effects of global climate change on high elevation

ecosystems (Maui, Big Island) • Climate and climate change (Hawai‘i)

Land-Cover Change Research:

SE Asia • Deforestation effects on local hydrological processes

(streamflow and soil erosion) • Forest fragmentation effects on hydrological processes

(transpiration and overland flow) • Effects of forest roads on hydological processes

(streamflow and soil erosion) • Effects of land-cover change and climate change on

watershed processes • Impacts of rapidly expanding rubber cultivation on energy,

water, and carbon dynamics

Pang Khum THAILAND

Lisu

Karen

Streamgage

Flux tower

Shifting cultivation

Pang Khum THAILAND

Soil Erosion

Roads

Farming steep slopes

Sediment Delivery

Altered Hydrology

Landscape Fragmentation

Ban Tat Hamlet VIETNAM

CHINA: Nam Ken Field Sites

NASA PROJECT

67 Km2

THAILAND: Mae Sa Field Sites

85 Km2

CHINA: Nam Ken Field Sites

NASA PROJECT

67 Km2

Maite Guardiola found an unusual dip in soil moisture in the dry season at the rubber site.

Water and Carbon Dynamics of Rubber Plantations in Non-Tradition Growing Regions of Southeast Asia

Thomas Giambelluca Ryan Mudd Alan Ziegler Maoyi Huang Wen Liu Michael Nullet Qi Chen Jefferson Fox

University of Hawai‘i at Mānoa University of Hawai‘i at Mānoa

National University of Singapore Battelle Pacific NW National Laboratory

University of Hawai‘i at Mānoa University of Hawai‘i at Mānoa University of Hawai‘i at Mānoa

East-West Center

Traditional and non-traditional rubber-growing regions

Jeff Fox, EWC, 2010

Jeff Fox, EWC, 2010

Jeff Fox, EWC, 2010

Jeff Fox, EWC, 2010

Rubber distribution in 2009 in MMSEA derived from MODIS 250m NDVI time series

Jeff Fox, EWC, 2010

Prior Study

Guardiola-Claramonte M, Troch Ziegler A, Giambelluca TW, Vogler JB, Nullet M (2008)

Local hydrologic effects of introducing non-native vegetation in a tropical catchment. Ecohydrology 1: 13–22, DOI: 10.1002/eco.3.





Research Questions Hydrology of Hevea brasiliensis Plantations

• What are the hydrological consequences of conversion of land to rubber plantations in non-traditional rubber growing areas?

• What are the rates of ET in rubber stands, and how does it compare with other land-cover types in the region?

• To what extent are dry-season basin water storage affected by water use of rubber?

Tower Sites

Jeff Fox, EWC, 2010

Som Sanuk

CRRI

Instruments and Observations Micrometeorological instruments installed at two rubber (Havea brasiliensis) plantations to measure water, energy, and carbon exchange

Som Sanuk, Nong Khai, NE Thailand Trees planted in 1992 Tower installed February 2009

CRRI, Kampong Cham, Cambodia Trees planted in 2004 Tower Installed September 2009

Tower Instrumentation Cambodia Rubber Research Institute

Kampong Cham, Cambodia

3 air temperature sensors (TC wire, Omega) 10 biomass temperature sensors (TC wire, Omega)

3 dimensional sonic anemometer (CSAT3, Campbell Scientific)

infrared gas analyzer (LI-7500, Licor)

PAR sensor (LI-190, Licor)

4 component radiation (NR01, Hukseflux)

Temperature and relative humidity (HMP45, Vaisala)

3 wind speed sensors for wind height profile (014A, Met one)

2 Rain gauges (TI-525, Texas Instruments)

•Wind speed and direction (05106, RM young)

Underground sensors

• 2 soil temperature sensors (20 cm TC probes, Campbell Scientific)

• 4 soil heat flux plates (HFP01, Hukseflux)

• 5 TDR soil moisture probes – 30 cm (CS616, Campbell Scientific)

– 4 cm horizontal – 30 cm vertical – 1 m vertical – 2 m vertical – 3 m vertical

• 5 ADR soil moisture sensors

(Theta Probe, DeltaT) – in 2 stands (2001 and 2004) – 5, 10, 20, 30, and 50 cm all

horizontal

Collaboration with Kumagai Lab of Kyushu University for sap flow measurements

Sap

flux

(kg

m-2

s-1)

0

0.02

0.04

0.06

5/19 5/20 5/21 5/22 5/23 5/24 5/25 5/26

Som Sanuk, Thailand

Som Sanuk, Thailand

CRRI

Preliminary Eddy Flux Results from Som Sanuk Annual Mean Diurnal Cycles

-100

0

100

200

300

400

500

600

0:00 3:00 6:00 9:00 12:00 15:00 18:00 21:00 0:00

RnetGHLE

Mean Rnet = 124 W m-2

Mean G = 2 W m-2

Mean H = 27 W m-2

Mean ET = 87 W m-2

ECE = 8 W m-2

Rubber Energy BalanceSom Sanuk, NE Thailand

Preliminary Eddy Flux Results from Som Sanuk

-20

0

20

40

60

80

100

120

140

160

180

Feb-09 Apr-09 Jun-09 Aug-09 Oct-09 Dec-09 Feb-10 Apr-10

RnetGHLE


Seasonal Cycle Related to Leaf Area

-20

0

20

40

60

80

100

120

140

160

180


RnetGHLE


0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5


17 yr old

12 yr old

6 yr old

Preliminary Eddy Flux Results from Som Sanuk: Mean Diurnal NEE Cycles

NEE (µmol m-2s-1)

-30

-25

-20

-15

-10

-5

0

5

10

0 6 12 18 24 30 36 42 48

30-minute Timesteps

NE

E

Jan

Dec

Nov

OctSepAug

JunJul

May

Preliminary Eddy Flux Results from Som Sanuk: Mean Diurnal NEE Cycles

-30

-25

-20

-15

-10

-5

0

5

10

NEE

Feb 09 Mar 09 Apr 09 May 09 Jun 09 Jul 09 Aug 09 Sep 09 Oct 09 Noc 09 Dec 09 Jan 10 Feb 10 Mar 10

NEE (µmol m-2s-1)

Mean Annual ET: 1100 mm

Site Land Cover LE:Rnet Borneo Tropical rainforest 0.89

Amazon Tropical rainforest 0.86

Som Sanuk Rubber plantation 0.70 Chiang Mai Hill evergreen 0.60

Mato Grosso Transitional forest 0.66

Weimin Ju，Fangmin Zhang, Jingming Chen, Shuanghe Shen, Shaoqiang Wang, Guirui Yu, Xinquan Zhao, Shijie Han, J. Asanuma (2010) Trends of evapotranspiration in East Asia from 1982 to 2006 simulated using a remote sensing-driven ecological model. Presented at HESSS2, 22 June 2010, Tokyo.

Summary • Rubber ET may be higher than forest ET • Seasonal cycle significantly changed with lower Sep-Jan ET

and higher Mar-Jul ET • Question:

– What effect does the altered annual cycle have on basin water storage and river discharge at the start of rain season?

• Further work: – Continued monitoring-both sites – Integrate EC and Sapflux observations – Leaf level measurements – Carbon stocks and budget

Evapotranspiration in Native and Invaded Tropical Montane Cloud Forest in Hawai‘i

Thomas W. Giambelluca John K. DeLay Mami Takahashi Ryan G. Mudd

University of Hawai‘i at Mānoa Maoyi Huang

State University of New York-Buffalo Gregory P. Asner Roberta E. Martin

Carnegie Institution for Science Michael A. Nullet

University of Hawai‘i at Mānoa

Photo: Trade Wind Fruits

Strawberry Guava (Psidium cattleianum)

Photo credit: Michelle Clapper, USGS-BRD, UH

• Grows fast • Invades quickly • Already widespread in Hawai‘i • Difficult to eradicate • High stem density • Smooth bark


• State of Hawai‘i lists 106 highly invasive plant species in the Islands • Many tree species have been found to be invasive

Species Invasion in Hawaiian Forests

Field Study of Invasive Tree Impacts

• Compare Native (Thurston) and Invaded (Ola‘a) Sites • Water and Carbon Dynamics at Stand Level • Transpiration of Different Species • Fog Interception • Rainfall and Fog Water Partitioning

Photo credit: Michelle Clapper, USGS-BRD, UH


Field Sites

• Invaded Forest Site – ‘ōhi‘a forest invaded by

Psidium cattleianum (strawberry guava)

• Native Forest Site – Metrosideros

polymorpha (‘ōhi‘a) – Cibotium spp. (hapu‘u;

tree fern)

Epiphyte Study Master’s Student, Ryan Mudd

Thurston Ola‘a

Biomass (t ha-1) 2.57 0.89

Surface Area per Ground Area (%) 26.5 15.5

Water Storage Capacity (mm) 1.48 0.59

LEinvaded 27% higher

Difference is here. LEnative has lower minimum

Stand-level Comparison Eddy Covariance Measurements

Dry Canopy: LEinvaded 53% higher

Dry Periods

Transpiration enhanced at invaded site.

During dry canopy periods, when physiological control over gas exchange is important, ET is much higher in the invaded stand. Why?

Photo credit: Forest & Kim Starr

Native: ‘Ōhi‘a

Invasive: Guava

We looked to our sapflow measurements for answers.

Sapflow Study PhD Student, John DeLay

Sample period mean sapflow velocities: Native ‘Ōhi‘a 3.3 Native Ilex 3.6 Native Olapa 3.3 Invasive Guava 2.7

Are sapflow velocities higher in guava?

Stand Basal Area

Basal Area-Xylem Area Large ‘Ōhi‘a Small ‘Ōhi‘a Guava

16% Xylem 50% Xylem 100% Xylem

Based on 400-m2 survey areas

Basal Area (cm2) Xylem Area (cm2)

Native Invaded Thurston Invaded ‘Ōhi‘a 19195 4795 3000 2424 Ilex 1760 0 800 0 Guava 0 5392 0 5392 Cheirodendron 0 859 0 859 Total 20955 11046 3800 8675 Sapwood/Basal 0.18 0.79

How about the effects of canopy wetting?


48%56%56%

58%

36%34%

18%

27%

0%

10%

20%

30%

40%

50%

60%

PE Transpiration PE Transpiration

Native Site-‘Ōhi‘a Invaded Site-Guava

Am

ount

Rel

ativ

e to

Dry

Lea

f Con

ditio

ns

Partially Wet Wet

Leaf Wetness Effects

Leaf Wetness Effect (-)

No Leaf Wetness Effect

Canopy Water Balance Study Master’s Students Ryan Mudd and Mami Takahashi

Throughfall Measurements

Stemflow Measurements

Single-Layer Canopy Water Balance Model

Canopy

RF

CWI

IE

FF FF

TF SF

Wet-Canopy Evaporation vs Transpiration

0.00

0.05

0.10

0.15

0.20

0.25

0:00 3:00 6:00 9:00 12:00 15:00 18:00 21:00 0:00

Wet-Canopy EvapTotal ETTranspiration

Native

52%

48%

Mean Diurnal Cycle June 2007-May 2008

0.00

0.05

0.10

0.15

0.20

0.25

0:00 3:00 6:00 9:00 12:00 15:00 18:00 21:00 0:00

Wet-Canopy EvapTotal ETTranspiration

Invaded

36%

64%

Canopy Water Balance: Native vs. Invaded

IE EC ET Total ET Transpiration Native (mm yr-1)

500 1249 961 461

Invaded (mm yr-1)

396 1392 1102 706

Diff -21% +11% +15% +53%

Implications For Regional Water Resources: • Guava invasion has significant

negative impact on ground-water recharge

For Dynamics of Tree Invasion: • High stem density and small

diameter stems favor higher transpiration; improves carbon assimilation and growth?

• Gas exchange uninhibited by leaf wetting


Thank You

[email protected]

Documents

Research in Tropical Ecohydrology - CTAHR Website in Tropical Ecohydrology ... Hill evergreen : 0.60 . ... Wet-Canopy Evaporation vs Transpiration . 0.00 0.05 0.10 0.15 0.20 0.25