Aastrup, P., Nymand, J., Raundrup, K., Lauridsen, T.L., Krogh, P.H., Schmidt, N.M., Illeris, L. & Ro-Poulsen, H. 2009: NuukBasic. Conceptual design and sampling procedures of the biological programme of NuukBasic. National Environmental Research Institute, Aarhus University. 70 pp. NERI Technical Report No. 745.
Below is given a short overview of all monitoring elements. The following sections give detailed descriptions of each element.
Plants
Table 1 (please see full report for Table 1) gives an overview of the monitoring of plants.
The NERO-line
The NERO line is a permanent vegetation transect which was established in July 2007 in order to monitor future changes in the distribution and composition of vascular plant species in the plant communities. Surveys of the transect will take place with 5 year intervals. It is intended to include mosses and lichens in the monitoring programme in the following years.
The concept relies on the assumption that changes in the distribution of plant communities can be seen by changes of boundary lines between vegetation zones. Therefore each boundary between vegetation zones has been marked by pegs. The species composition of the vegetation zones has been documented by Raunkjær analyses. Immigration of new species is assumed to be documented by the surveys with five year intervals. The concept is also used for the ZERO-line in Zackenberg in high arctic North East Greenland (Fredskild & Mogensen 1996, Bay 2001, 2006).
Movement of zones is documented by the position of pegs, while changes in species composition are recorded by Raunkjær–analyses.
Reproductive phenology
It is expected that plant phenology will give an early and distinct response to climate change. This has already convincingly been shown in Zackenberg. In Nuuk we follow four species: Salix glauca, Loiseleuria procumbens, Eriophorum angustifolium (only total flowering) and Silene acaulis. These species were chosen because they are widely distributed in the area and they cover a spectrum of different growth forms (deciduous dwarf shrub, evergreen dwarf shrub, graminoids and cushion forming herb), and they are comparable to species monitored in Zackenberg.
Please see full report for Table 1
For each species four observation plots were established. The specific sites of the plots were chosen in order to cover the ecological amplitude of the species with respect to duration of snow cover, difference in soil moisture at the site and altitude. The size of each plot varies depending on the abundance of individual flowering shoots of the species in question.
Total flowering
Total flowering in the reproductive phenology plots is followed for Salix glauca, Loiseleuria procumbens, Eriophorum angustifolium, and Silene acaulis. The number of flowers is counted at peak flowering as the total number of buds, flowers/catkins and senescent flowers/catkins.
Normalized Difference Vegetation Index (NDVI)
The progression in vegetation greenness is followed along the vegetation transect and in the plant phenology plots by measuring NDVI with a scanner. NDVI is used as an index of plant production and vigorousness. The scanner measures the spectral reflectance of the plant canopy.
CO2 flux plots
The CO2 flux is important for understanding the balance between CO2 emission and uptake. This study aims at documenting the present state, but it will also provide data from manipulations simulating increased temperature, increased cloud cover, shorter growing season, and longer growing season.
UV-B exclusion
UV-B radiation will increase as a result of the expected depletion of the ozone layer in the atmosphere. We monitor the effect of increased UV-B radiation on plant stress is monitored indirectly by measuring chlorophyll fluorescence in three series of plots: Controls, plots with a filter excluding UV-B, and filter controls with film without exclusion of UV-B. Measurements of chlorophyll fluorescence are carried out on Betula nana and Vaccinium uliginosum in a mesic dwarf shrub heath dominated by Empetrum nigrum and with Betula nana and Vaccinium uliginosum as subdominant species.
Arthropods
Arthropods are sampled by means of yellow pitfall traps. The traps are emptied weekly throughout the summer season (early June – late September). At the time being, samples are stored at Greenland Institute of Natural Resources (GINR) awaiting final decision of the future of the programme. Presently there is no financing for determination of the sampled specimens.
Microarthropods and decomposition
Microarthropods are sampled in soil cores from which the organisms are extracted in an extractor by gradually heating up. Microorganisms are determined at NERI, Dpt. of Terrestrial Ecology.
The rate of decomposition of filter paper is measured in the microarthropods plots.
Birds
The avifauna is monitored with special emphasis on small passerine birds representing the highest trophic level. Breeding phenology (first egg dates, hatching, fledging) is monitored throughout the season on an ad hoc basis.
Weekly counts of birds are carried out at census points during the entire season from May untill all the birds have left the area in August-September. Other bird observations are recorded ad-hoc during the entire field season.
Mammals
Only few terrestrial mammals occur in the study area: Arctic fox Alopex lagopus, arctic hare Lepus arcticus, and caribou Rangifer tarandus. The first year’s observations, however, indicate that mammals are not observed very often. In 2007 only arctic fox was actually observed, and there were no new signs like footprints or droppings of caribou. In 2008 two caribou were observed at one occasion and fresh foot prints were also observed during the season. All observations of mammals will be recorded ad-hoc. If arctic fox dens are discovered, reproduction will be followed.
Lakes
The two sampling lakes are located in the Kobbefjord catchment area in the bottom of Kobbefjord (Badesø 64º07’48’’N, 51º21’23’’ W and Qassi Sø, 64º09’11’’N, 51º18’18’’ W).
Monitoring include ice cover, water chemistry, physical conditions, species composition of plankton, vegetation, bottom organisms and fish. Physical-chemical parameters, phytoplankton and zooplankton are monitored monthly in the period when the lakes are ice-free.
Full report in PDF format (4 MB)
