A year and a half after the outbreak of the corona pandemic, scientists, technical staff, stakeholders and guests gathered for a scientific exchange on the activities of the ICOS Germany network. The hybrid-format event was hosted by colleagues from the Technical University Dresden in Tharandt. In addition to status reports from the three domains (atmosphere, terrestrial ecosystems, oceans) and the laboratories, current scientific studies were presented and discussed.
One thematic focus was on contributions from German forest sites. It was shown, among other things, how CO2 and water fluxes behave after clear cuts and in forests on peat soils. Furthermore, the importance of long-term measurements was pointed out and the main meteorological and climate-related drivers for the CO2 exchange were outlined.
Further topics included general methodological work as well as comparative studies from the field of ocean measurements and new results from various research activities on greenhouse gas exchange in the Baltic Sea. The status of the establishment of an integrated greenhouse gas monitoring and networking with the remote sensing community was also reported.
In addition, scientists from ICOS Germany are participating in a special study that was initiated with regard to the warm winter of 2019/2020 with the subsequent transition to time of the corona lockdown, featuring a temporary reduction in traffic and industrial emissions. Another specific study that is currently starting includes a synthesis of the carbon fluxes of European arable sites. Here it is examined how the current management measures in combination with the prevailing meteorological conditions affect the CO2 fluxes and the carbon stocks in arable soils.
In the future, urban measuring stations will also be integrated into the ICOS Germany network. The first location will be the Berlin eddy-covariance station on Rothenburgstrasse. A concept for the holistic assessment of urban greenhouse gas emissions is being developed in the EU project PAUL (Pilot Application in Urban Landscapes) with strong German participation.
Since no public event was allowed to take place due to the corona situation, the hosts provided information about their research work in the TU Dresden cluster as part of a live stream, so that ICOS Germany could be presented to a wider public.
The three-day meeting was rounded off by an excursion to the Tharandt Forest anchor station, a stand of old spruce south of Dresden, being labelled as Class-1 ecosystem ICOS site. In addition to a variety of measurements, the CO2 and energy exchange between the forest and the atmosphere have been continuously determined since 1996. The observations form the longest time series of continuous eddy-covariance measurements in Germany. The spruce stand in the Tharandt Forest is over 130 years old with an average height of 30 m. The site has been cultivated since 1811 (including clearings, plantings, liming). The current measures for forest conversion (including planting beech and fir) aim to reduce the currently dominant share of spruce in favor of a mixed forest. The last major clearings took place in 2002 (removal of 60 m3 ha-1), 2011 and 2016 (53 m3 ha-1 each).