Table 2.

A summary of the magnitude of Na⁺ fluxes in algae and plants, based on area of the membrane

	NaCl (mm)	Na flux (nmol m–2 s–1)
Freshwater algae	0.1	5	MacRobbie (1971a)
Freshwater algae	1–2	1–20*	Raven (1976)
Marine algae	550	170	Raven (1976)
Suaeda maritima roots	340	262	Yeo and Flowers (1986)
Suaeda maritima leaves	66†	17	Flowers and Yeo (1986)
Arabidopsis thaliana root protoplasts§	100	700	Volkov and Amtmann (2006)
Eutrema halophilum root protoplasts§	100	150	Volkov and Amtmann (2006)
Cynodon dactylon gland	75$	408	Oross et al. (1985)
Limonium perezii gland	300	4200‡	Faraday and Thomson (1986a)

*Flux across the plasma membrane in the light.

†Estimated xylem concentration (Clipson and Flowers, 1987).

‡Efflux was, in the words of the authors (Faraday and Thomson 1986a), calculated as though ‘evenly distributed across the non-transfusion zone plasma membrane of the secreting gland’.

$Fed to the cut shoots.