Using networks of eddy covariance towers to explore linkages between ecosystem

structure and function

Marcy Litvak

Assistant Professor, Biology Department, University of New Mexico

YESS Workshop October 22-24, 2007

3-D Eddy Covariance

Sensor

•Direct measurement of net ecosystem exchange of carbon, water and energy

•Advantages of using networks of these towers (Ameriflux, FLUXNET)

How does carbon cycling in boreal forests change following wildfire?

1989 1981

19641850

1930

5km

1850

1930

1964

1981

1989

1998

1951 1974 1991 200441.1% 43.3 % 54.8% 63.4%

Freeman Ranch Edwards Plateau in central Texas

Woody encroachment in karst terrain: implications for regional carbon, water and energy cycles

Day of Year

0 100 200 300

Cu

mu

lativ

e c

arb

on

ga

in (

g m

-2)

-100

0

100

200

300

400

GrasslandTransitionForest

2005

Positive = carbon sinkNegative = carbon source Day of Year

0 100 200 300

Cu

mu

lativ

e E

T (

mm

)

0

200

400

600

800

GrasslandForestTransition

2005Twine correction

ET = 13 mm

Grassland

Day of Year

140 180 220

NEE

(g

m-2

d-1

, C)

-8

-6

-4

-2

0

2

4

6

Forest

Day of Year

140 180 220

Day of Year

140 180 220

Transition

EPSCoR: Experimental Program to Stimulate Competitive Research – Hydrology

Goal: Leadership in instrumentation and algorithm development for regional hydrologic modeling and ET estimation in semiarid environments

Ground-BasedMeasurements(input and validation forModels)

Satellite Imagery(input for maps of ET, vegetation change)

Geospatial Integrated Modeling & Geographic Information SystemDatabases and Products

NM EPSCoRHydrology

NM EPSCoR Core Network

Rio Grande riparian corridor

Lower Rio Grande agriculture and open water

Arid upland (grassland, desert, juniper savanna, piñon-juniper, ponderosa pine, mixed conifer)

PiPiññon mortality in on mortality in pipiññon-juniper on-juniper

woodland in NMwoodland in NM

Link to workshop

Eddy covariance towers give integrated measurement over large area

Need detail of how principal components of ecossytem function to interpret

Dispersed sensors across tower footprint crucial

Interested in learning about more efficient ways to link sensors in one tower footprint, across network, and synthesis efforts