Table 1.

Effects of selected abiotic factors on N₂ fixation in different moss species from boreal and arctic environments.

Moss species	Abiotic factor	Effect on N2 fixation	References
Sphagnum riparium	Temperature	+ up to 15°C; Topt 16°C	Basilier and Granhall, 1978
Brachythecium subplicatum	Temperature	+ up to 25°C; Topt 25–27°C	Smith, 1984
Pleurozium schreberi-Nostoc –associate	Temperature	Tmax 13°C	Gentili et al., 2005
Pleurozium schreberi-Calothrix –associate	Temperature	Tmax 30°C	Gentili et al., 2005
Pleurozium schreberi	Temperature	+ Topt 25°C	Gundale et al., 2012a
Hylocomium splendens	Temperature	−	Gundale et al., 2012a
Hylocomium splendens	Temperature	No effect	Sorensen et al., 2012
Aulacomnium turgidum	Temperature	−	Sorensen et al., 2012
Pleurozium schreberi	N-addition	− (4.25; 25.5 kg N ha−1 yr−1)	Zackrisson et al., 2004
Pleurozium schreberi	N-addition	− (3; 6; 12; 50 kg N ha−1 yr−1)	Gundale et al., 2011
Hylocomium splendens	N-addition	− (100 kg N ha−1 yr−1)	Sorensen et al., 2012
Aulacomnium turgidum	N-addition	− (100 kg N ha−1 yr−1)	Sorensen et al., 2012
Brachythecium subplicatum	Moisture	+	Smith, 1984
Pleurozium schreberi	Water addition	+	Gundale et al., 2009
Pleurozium schreberi	Water addition	+	Gundale et al., 2012b
Pleurozium schreberi	P-addition	+	Zackrisson et al., 2004
Hylocomium splendens	P-addition	No effect	Zackrisson et al., 2009
Sphagnum riparium	P-addition	+	Basilier and Granhall, 1978
Brachythecium subplicatum	P-addition	−	Smith, 1984

P, Phosphorus; N, Nitrogen; T_opt, optimum temperature; T_max, maximum temperature; positive, +; negative, −; or no effects are given.