P1254413685sOpNf

1
Chinese Terrestrial Ecosystem Flux Network
(ChinaFLUX)
Guirui Yu
Institute of Geographical Sciences and Natural
Resources Research, CAS
2
Contents

• About ChinaFLUX
• Site description and operation
• Data processing
• Results
• Prospects

3
About ChinaFLUX
The ChinaFLUX was established in 2002 based on
the Chinese Ecosystem Research Network (CERN), a
backbone infrastructure of ecological research in
China
CERN is supported and managed by Chinese Academy
of Sciences (CAS), consisting of 36 research
stations nationwide
4
Objectives
The ChinaFLUX Network aims to obtain quantitative
and mechanistic understanding of ecosystem
dynamic responses to environmental changes by

• establishing a coordinated research network for
  guiding, collecting and synthesizing data of CO2,
  water, and energy fluxes of major terrestrial
  ecosystems in China
• providing quantitative, mechanistic information
  on environmental and biotic controls over
  ecosystem processes
• Developing and verifying mechanistic models for
  diagnostic and prognostic analysis of ecosystem
  changes at different scales

5
Scientific questions

• Magnitude and spatio-temporal variability of
  carbon, water and energy fluxes of major
  terrestrial ecosystems
• Environmental and biological mechanism affecting
  the magnitude and variability of the fluxes
• Coupling of water, C and nutrient cycles in
  different ecosystems
• The linkage of the fluxes with ecosystem
  functions (e.g. productivity, carbon
  sequestration, water and nutrient cycling)
• Spatial patterns and temporal trends in the
  fluxes and ecosystem functions under
  environmental change, human disturbance and
  management

6
Strategically planning and designing
ChinaFlux is unique in central planning, funding
and management

• The sites are strategically located to represent
  ecosystems in different biomes at different
  status (natural and managed)
• Some sites are located along ecological
  transects for facilitating studies on the
  environmental control mechanisms

7
(No Transcript)
8
Flux site description and operation
9
Flux site description
10 ecosytems with 2-year measurements
10
Changbai Mountain Station
Height 62.8 m
11
Qianyanzhou Station
Height 45.04 m
12
Dinghushan Station
13
Xishuangbanna Station
14
Grassland in Inner Mongolia
15
Haibei Grassland Station
Alpine shrub
Alpine swamp
Alpine meadow
16
(No Transcript)
17
Dangxiong at Tibetan Plateau
18
Yucheng Agricultural Station
19
Close-path Eddy Covariance system (CPEC)
Open-path Eddy Covariance system (OPEC)
20

• ChinaFLUX promotes
• continuous, long-term eddy flux measurements
  using uniform standard and protocols at all sites
• using various ancillary techniques, such as
  stable isotope measurements, biometric
  inventories, and remote sensing to measure
  ecosystem changes in processes and structures

21
Background data investigation

• micrometeorology
• photosynthesis
• Soil respiration
• Other Background data

22
ChinaFlux has been registered in FLUXNET
23
Data processing
24
ChinaFlux has centralized data management system
Data storage Data processing Data synthesis
Data sharing
CERN Synthesis Center
25
Database construction
26
Data processing procedures
27
Results
28
Diurnal variations of NEE
Haibei
Changbaishan
Qianyanzhou
Monthly averages of hourly mean CO2 exchange
29
Seasonal variations of NEE,Re, GEP for forests
NEE,Re,GEP(g CO2 m-2 d-1)
30
Seasonal variations of NEE, Re, GEP for grassland
NEE,Re,GEP(g CO2 m-2 d-1)
31
Seasonal variation of NEE, Re, GEP for cropland
Winter wheat
Winter wheat
maize
maize
NEE,Re,GEP(g CO2 m-2 d-1)
32
Seasonal variations of NEE, Re, GEP for
Changbaishan
Seasonal course of daily integrated FGPP (a), RE
(b), FNEE (c) and monthly averaged z (d). The
stair line is the monthly mean value of the
corresponding variable.
33
Response of photosynthesis to PAR
34
Response of photosynthesis to PAR
Seasonal variations of ecosystem a, Pmax and Re
in 2003
35
Response of photosynthesis to PAR
36
NEE vs temperature
Seasonal change of daily mean CO2 exchange and
air temperature in different alpine ecosystems
The top, middle and bottom panels are for the
alpine meadow, shrub and swamp ecosystems at
Haibei station, respectively.
37
Ecosystem respiration vs temperature
Qianyanzhou
Changbai Mountain
Haibei
38
BEPS model
Data and model comparison
39
CO2 flux of the Changbai Mountains
NEP (gC m-2)
Day of year
40
Latent heat of the Changbai Mountains
LE(W/m-2)
Day of year
41
SMPTSB model

42
Data and model comparison

43
Chinese Terrestrial Ecosystem Flux
Network ChinaFlux
achievements
Workshop on flux observation in Asia was held
successfully in Beijing in 2003
Special issue inScience in China, Series D, in
2004, systematically reported the results
obtained by each site of ChinaFlux
Special issue inAgricultural and Forest
Meteorology, 9 papers focused on typical issues
in ChinaFlux observation has passed the
peer-review
44
ChinaFLUX Prospects
45
Chinese Terrestrial Ecosystem Flux
Network ChinaFlux
Assimilation of data from various measurements
into mechanistic models
Remote sensing
Data-model fusion and simulation
Flux and stable isotope measure-ments
Biometric inventories
ChinaFlux
CERN
46
(No Transcript)