Table 1 Description and location of the datasets plant functional traits and associated data from an ITEX warming experiment and two elevation gradients, with and without marine nutrient input from nesting seabirds, near Longyearbyen, Svalbard.

i

Plant community composition

1,273^a

689^b

26 vascular plants, 1 fungus, 8 lichens, 22 bryophytes^a

50 vascular plants^b

2003, 2009, 2015^a

2018^b

Raw data⁶⁶, clean data⁶⁶, code⁶⁷

ii

Vegetation structure and height

61^a

756^b

2003; 2009, 2015^a

2018^b

Raw data⁶⁶, clean data⁶⁶, code⁶⁷

iii

Vascular plant and bryophyte traits

5,339^a

11,345^b (10,297 vascular plants; 1048 bryophytes)

19 vascular plants^a

31 vascular plants, 19 bryophytes^b

2018^a,b

Raw data⁶⁶, clean data⁶⁶, code⁶⁷

vi

Soil carbon and nitrogen

70^b

2022^b

Raw data⁶⁶, clean data⁶⁶, code⁶⁷

v

Ecosystem CO₂ fluxes

raw flux measurements

129^a

59^b

2018^a,b

Raw data⁶⁶, clean data⁶⁶ code⁵

vi

Remote sensing

7 sites, 28,500 (x5) individual multispectral images;

340 leaf spectroscopy readings,

117 ground-truthing points^a,b

18 species of moss, graminoid, and dwarf shrub^a,b

2018^a,b

Clean data⁶⁶

vii

Climate data

station: 815,339^a

loggers: 937,388^a

162^b

station: 2015–2018^a

loggers: 2004–2005; and 2015–2018^a

2018^b

Raw data⁶⁶, clean data⁶⁶, code⁶⁷