The Arctic terrestrial food web includes the exchange of energy and nutrients. Arrows to and from the driver boxes indicate the relative effect and counter effect of different types of drivers on the ecosystem. STATE OF THE ARCTIC TERRESTRIAL BIODIVERSITY REPORT - Chapter 2 - Page 26- Figure 2.4

Geographic area covered by the Arctic Biodiversity Assessment and the CBMP–Terrestrial Plan. Subzones A to E are depicted as defined in the Circumpolar Arctic Vegetation Map (CAVM Team 2003). Subzones A, B and C are the high Arctic while subzones D and E are the low Arctic. Definition of high Arctic, low Arctic, and sub-Arctic follow Hohn & Jaakkola 2010. STATE OF THE ARCTIC TERRESTRIAL BIODIVERSITY REPORT - Chapter 1 - Page 14 - Figure 1.2

Marine primary productivity is not available from the NASA Ocean Color website. Currently the best product available for marine primary productivity is available through Oregon State University’s Ocean Productivity Project. A monthly global Net Primary Productivity product at 9 km spatial resolution has been selected for this analysis. The algorithm used to create the primary productivity is a Vertically Generalized Production Model (VGPM) created by Behrenfeld and Falkowski (1997). It is a “chlorophyll-based” model that estimates net primary production from chlorophyll using a temperature-dependent description of chlorophyll photosynthetic efficiency (O’Malley 2010). Inputs to the function are chlorophyll, available light, and photosynthetic efficiency.

Regional differences are more pronounced in the insectivore guild (Figure 3-24). Although diversity of waders was moderate in the East Asian–Australasian Flyway, 88% (15 of 17) of taxa with known trends were declining—the largest proportion of any group. Both short-term (the last 15 years) and long-term (more than 30 years) trends were available for 157 taxa. Trends were unchanged over the two time periods for 80% of taxa, improved for 11% and worsened for 9%.. STATE OF THE ARCTIC TERRESTRIAL BIODIVERSITY REPORT - Chapter 3 - Page 56 - Figure 3.24

Trends and distribution of muskoxen populations based on Table 3-5. Modified from Cuyler et al. 2020. STATE OF THE ARCTIC TERRESTRIAL BIODIVERSITY REPORT - Chapter 3 - Page 79 - Figure 3.30

Many population counts of gregarious migrant species, such as waders and geese, take place along the flyways and at wintering grounds outside the Arctic which stresses the importance of continued development of movement ecology studies. Monitoring of FEC attributes related to breeding success and links to environmental drivers within the Arctic takes place in a wide network of research sites across the Arctic, although with low coverage of the high Arctic zone (Figure 3-25) STATE OF THE ARCTIC TERRESTRIAL BIODIVERSITY REPORT - Chapter 3 - Page 58 - Figure 3.25

The Snow Covered Area product is based on a Normalized Difference Snow Index(NDSI), which is similar to NDVI, but exploits different bands in the equation (Equation 3),namely Green (Band 4) and Short Wavelength Near-infrared (SWNIR, Band 6). It isimportant to note that the Band 6 sensor on MODIS Aqua malfunctioned shortly after launch,so Snow Covered Area from the Aqua sensor is calculated using Bands 3 and 7. This mayintroduce errors in identifying snow in vegetated areas, as the use of Band 7 results in falsesnow detection. For this reason the MODIS Terra product has been provided for the CAFF-system.

Population estimates and trends for Rangifer populations of the migratory tundra, Arctic island, mountain, and forest ecotypes where their circumpolar distribution intersects the CAFF boundary. Population trends (Increasing, Stable, Decreasing, or Unknown) are indicated by shading. Data sources for each population are indicated as footnotes. STATE OF THE ARCTIC TERRESTRIAL BIODIVERSITY REPORT - Chapter 3 - Page 70 - Table 3.4

The MODIS Land Cover Type product is created yearly using three landclassification schemes; the International Geosphere Biosphere Programme (IGBP)classification scheme, the Univertiy of Maryland (UMD) classification scheme, and aMODIS-derived Leaf Area Index /Fraction of Photosynthetically Active Radiation(LAI/fPAR) classification scheme (Table 3). The International Geosphere Biosphere Programme (IGBP) identifies seventeenland cover classes, including eleven natural vegetation classes, three non-vegetated landclasses, and three developed land classes. The product provided is derived using the samealgorithm as the 500 m Land Cover Type (MOD12Q1), but is on a 0.05° Climate Model Grid(CMG), that has been clipped to the pan-Arctic extent. The UMD classification scheme issimilar to the IGBP classification scheme, but it excludes the Permanent wetlands,Cropland/Natural vegetation mosaic, and the Snow and ice classes. The LAI/fPARclassification scheme is the smallest of the three, and focuses on forest structure; it only haseleven classes. All three land cover classification schemes are provided, but the IGBPclassification scheme is the most amenable to the Pan-Arctic region.

Temporal trends of arthropod abundance for three habitat types at Zackenberg Research Station, Greenland, 1996–2016. Data are grouped as the FEC ‘arthropod prey for vertebrates’ and separated by habitat type. Solid lines indicate significant regression lines at the p<0.05. Modified from Gillespie et al. 2020a. STATE OF THE ARCTIC TERRESTRIAL BIODIVERSITY REPORT - Chapter 3 - Page 39 - Figure 3.9