Table 1.

Surface water and sediment characteristics of 14 study sites in USA (California) and Europe; the Netherlands (NL) and France (Fr).

Site #	Site name	Location	Site type	Surface water				Sediment
				$\left[N{O}_3^{-}\right]$ (mM)	$\left[S{O}_4^{2-}\right]$ (mM)	pH	Salinity	%N	%C	Corg/N	%S	[Fe] μmol g−1 dry sed.	[As] nmol g−1 dry sed.	Mean grain size (μm)
1	Tresmes	Fr	River	480	0.27	7.7–8	0.5	0.11	2.53	19.1	0.11	11.70	Bdl	317.0
2	Créteil	Fr	Lake	20	5.8	8	0.5	0.05	0.70	11.6	0.10	5.53	Bdl	46.3
3	Waarde	NL	Estuary	60	9.1	8.2	5.5	0.08	0.85	9.1	0.11	41.13	94.53	115.7
4	Elkhorn Slough marsh	USA	Estuary	10	25.8	8	5.6	0.11	1.13	8.7	0.19	34.63	50.56	251.2
5	Elkhorn Slough	USA	Estuary	19	27.5	8	6.1	0.05	0.36	6.2	0.07	44.20	75.85	120.0
6	Baylands	USA	Salt marsh	420	24.4	7.5–7.6	17–19	0.20	1.75	7.6	0.24	108.68	52.45	16.8
7	Pescadero	USA	Estuary	140	8.0	8	15–25	0.04	0.17	3.6	0.19	31.76	Bdl	293.9
8	Hourdel salt marsh	Fr	Estuarine	0	1.30	8.7	25	0.10	0.77	6.6	0.21	24.13	57.08	53.7
9	Hourdel port	Fr	Estuary	60	1.10	8.9	25	0.11	0.82	6.2	0.13	18.18	34.59	81.8
10	Rattekaai	NL	Estuary	Bdl	23.0	8.7	27.2	0.88	7.25	7.1	2.04	112.11	229.42	63.6
11	Humboldt Bay	USA	Near shore marine	Bdl	29.3	6.5	33.5	0.10	1.08	9.7	0.16	54.90	38.70	45.2
12	North CA Coast	USA	Near shore marine	Bdl	28.8	7.9	34.0	0.07	0.73	9.0	0.36	59.29	49.54	7.0
13	Mono Lake boat launch	USA	Hyperalkaline lake	Bdl	98.1	9.8	79.6	0.09	1.06	10.2	0.19	9.68	696.62	298.4
14	Mono Lake Black point	USA	Hyperalkaline lake	Bdl	39.1	10.8	79.6	0.12	0.83	5.7	0.16	84.67	379.55	246.0

Bdl, below detection limit.

The detection limit for nitrate is 5 μM.