Flux Tower Sites, State of the Art, and Network Design

  • A. Johannes Dolman
  • Riccardo Valentini
  • Margriet Groenendijk
  • Dimmie Hendriks
Part of the Ecological Studies book series (ECOLSTUD, volume 203)

Direct observations of the exchange fluxes of water, energy, carbon dioxide, trace gases, and momentum have been possible since the 1960s. Most of this early work comprised campaigns of short duration, and has contributed substantially to our process understanding of surface atmosphere exchange. The data obtained in these studies were fundamental in assessing the validity of Monin-Obhukov similarity over natural surfaces, in testing resistance analogue formulations (e.g., Monteith 1965), and were also used to calibrate flux models against single site data. The seminal two volume work by J.L. Monteith “Vegetation and the Atmosphere” provides an excellent summary of the micrometeorology of natural vegetation of this period (Monteith 1976). It was also during this period that climate modelers became increasingly aware of the important role of the biosphere in climate. In the 1980s and 1990s, the early observational work was extended to study variability along climatic or other transects. The analysis of Valentini et al. (2000) describing the variation of net ecosystem exchange (NEE) of CO2 along a North-South gradient in Europe typifies this stage. New developments in technology (e.g., Moncrieff et al. 1998), such as the availability of “off the shelf” fast response instrumentation, gave opportunity to the development of the eddycovariance technique. The “la Thuile workshop” in 1994 which resulted in a special issue of Global Change Biology (Baldocchi et al. 1996) was fundamental in bringing together micrometeorologists and ecologists in studying exchange fluxes, not only of water and energy but also of carbon. At the political level, the Kyoto process provided extra impetus to these studies, particularly for carbon, although the direct relevance of flux measurements to the Kyoto process remains somewhat controversial (Körner 2003; Dolman et al. 2003). The data coverage (Fig. 11.1) of this FLUXNET network (Baldocchi et al. 2001) is now near global, from Siberian sites (Dolman et al. 2004) to tropical rainforest (Araújo et al. 2002). Since around 2000 the analysis has begun to take advantage of this near global coverage of sites, and studies have emerged of interannual variability, data assimilation, and continent scale estimation of carbon uptake (Knorr and Kattge 2005; Papale and Valentini 2003).


Network Design Gross Primary Production Sonic Anemometer European Forest Global Change Biology 


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Copyright information

© Springer Science + Business Media, LLC 2008

Authors and Affiliations

  • A. Johannes Dolman
    • 1
  • Riccardo Valentini
    • 2
  • Margriet Groenendijk
    • 1
  • Dimmie Hendriks
    • 1
  1. 1.Department of Hydrology and Geo-Environmental SciencesVU University AmsterdamAmsterdamNetherlands
  2. 2.Department of Forest Science and EnvironmentUniversity of TusciaViterboItaly

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