NUUK BASIC: The BioBasis programme

• Main Authors: Bay, Christian, Nymand, Josephine, Aastrup, Peter, Raundrup, Katrine, Krogh, Paul Henning, Lauridsen, Torben Linding, Lund, Magnus
• Other Authors: Jensen, Lillian Magelund, Rasch, Morten
• Format: Other Non-Article Part of Journal/Newspaper
• Language: English
• Published: Aarhus University, DCE - Danish Centre for Environment and Energy 2013
• Subjects: Nero; Nuuk; Empetrum nigrum; Silene acaulis; Snow Bunting; Lapland
• Online Access: https://pure.au.dk/portal/da/publications/nuuk-basic-the-biobasis-programme(29ecbf1a-6570-4a63-a960-4d4bf3fd7902).html; http://www.nuuk-basic.dk/fileadmin/Resources/DMU/GEM/Nuuk/nye/NERO_2013.pdf

The 2011 season was the fourth full season for the BioBasis monitoring programme. Generally, there is a high consistency in data collected during the four years indicating that the data and the procedures used are reliable and sound. A preliminary review of data related to fl owering and plant reproductive phenology indicates that 2011 was characterised by late fl owering, an extreme impact of the noctuid moth, Eurois occulta, and no rebudding events in Loiseleuria procumbens and Silene acaulis. The year 2011 had a late melt-off of snow so the recording period covers early June to early October. Loiseleuria procumbens fl owered one month later than the earliest year 2010. The buds of all the monitored species were heavily impacted by larvae of the noctuid moth, Eurois occulta. This is the second year in a row with impact of this moth species. The number of larvae peaked in early July with nearly 2000 trapped during one week. Because of the larvae impact, it was only possible to record of Salix glauca were eaten by the moth larvae. Consequently, the seed production was at a minimum this year. Generally, the NDVI (Normalized Difference Vegetation Index) values in the permanent plots were signifi cantly lower for Empetrum nigrum, Eriophorum angustifolium, and Salix glauca and they peaked later at the end of the growing season compared to previous years. The lower values are presumably caused by the heavy impact of the larvae. Generally, the NDVI values along the NERO line in the heaths and the copses were lower than the previous years, especially in the beginning of the season and reached the level from previous years in late August. The NDVI values peaked in the heaths by the end of the season. The fen plot reached the peak of NDVI later than in previous seasons and the greening was slower in the beginning of the growing season presumably due to the late snow melt. Generally, all plots functioned as sinks for atmospheric CO2 in August and September, whereas fl uxes were close to zero in June, July and October. Similar to earlier years NEE (Net Ecosystem Exchange) is more negative in C-plots (control) compared with T- and S-plots (increased temperature and shading, respectively). The ecosystem respiration showed a constant pattern of higher emissions in T-plots compared with other treatments, which can be explained by warmer and drier conditions leading to increased respiration rates. The highest rates of gross primary production were generally observed in C-plots, while especially S-plots showed lower GPP (Gross Primary Production) rates compared with other treatments. In general, there are huge variations in the number of trapped arthropod specimen within all taxonomical groups both within the season and between years. The peak number of specimens trapped is often reached in the beginning of the season. The most abundant group is Acarina, which peaks with more than 160 specimens trapped during one week. A microarthropods and arthropod isotope campaign was implemented in 2011 as an increasing number of studies have applied analysis of natural abundance of stable isotopes to soil invertebrate communities and primary producers. Soil, turf and detritus were sampled for determination of natural abundance of stable isotopes in invertebrates. the time of 50 % fl owering in one of the monitoring species. It is the latest date of 50 % fl owering ever recorded for Silene acaulis during the years of monitoring. The maximum number of buds of Loiseleuria procumbens is the largest number recorded since the monitoring programme started but all were eaten and no re-budding occurred later in the season. All the catkins The most common bird species were Lapland bunting and snow bunting as observed in previous years and there was a slight increase in numbers of Lapland bunting, snow bunting and northern wheatear over the years. There has been a decline in the numbers of redpolls since 2009. Both Badesø and Qassi-sø are oligotrophic lakes. However, nitrogen level has been increasing during the past four years, except for the dry year 2009, where the nitrogen level was very low, probably due to a reduced nutrient run-off. During the four-year period, a slight increase in chlorophyll a and consequently a small decrease in Secchi depth have been observed. The decrease in Secchi depth has not affected macrophyte growth. The depth limit of the macrophyte growth is slowly increasing particularly in Qassisø. The zooplankton community and biomass reflects the conditions in the two lakes. We fi nd a higher zooplankton biomass in the Qassi-sø (without fi sh) indicating a small predation pressure on zooplankton and consequently a slightly lower phytoplankton/zooplankton ratio compared to Badesø, which has fish and therefore a higher predation pressure on zooplankton.