Table 4.

Theil slope (single value) or quartile distance (25-percentile to 75-percentile) Theil slope values and probability (P) for statistically significant trends over the period 1996–2009 for some acidity-related parameters in total deposition (throughfall for pH), soil water, groundwater, and streamwater at the Swedish IM catchments

Parameter	Source	Aneboda		Gårdsjön		Kindla		Gammtratten
		Slope	P	Slope	P	Slope	P	Slope	P
SO42− meq m−2 year−1	Total deposition	−1.9	***	−2.2	**	−1.6	**	−0.7	**
NO3− meq m−2 year−1	Total deposition	nm		nm		nm		nm
Cl− meq m−2 year−1	Total deposition	nm		nm		nm		nm
BC meq m−2 year−1	Total deposition	nm		nm		nm		nm
ANC meq m−2 year−1	Total deposition	1.5	***	nm		1.3	**	1.0	**
pH year−1	Throughfall	0.03	***	0.04	***	0.03	***	0.01	*
pH year−1	Soil water	0.01 to 0.04	**	0.01 to 0.03	*	0.01 to 0.02	***	−0.03 to 0.01	ns
	Groundwater	−0.08 to −0.01	**	−0.02 to 0.01	ns	−0.05 to 0.02	**	−0.01 to 0.03	a
	Streamwater	0.013	**	0.007	ns	0.015	***	0.014	*
Alt μg l−1 year−1	Soil water	−58 to −3	ns	−39 to −13	ns	−35 to −15	***	−14 to 7	ns
	Groundwater	−7 to 74	ns	−78 to −32	**	−37 to 41	ns	−0.6 to 0.5	a
	Streamwater	0.7	ns	−30	***	−19	**	−1.3	ns
SO42− μeq l−1 year−1	Soil water	−13 to −4.4	***	−9.9 to −4.7	**	−8.4 to −6.7	***	−1.6 to −0.1	**
	Groundwater	−13 to −0.9	**	−13 to 8.9	**	4.7 to 0.1	ns	−2.9 to −0.8	a
	Streamwater	−7.3	***	−7.8	**	−6.8	***	−2.0	**
DOC mg l−1 year−1	Soil water	−0.2 to −0.1	ns	−0.2 to 0	**	−0.2 to 0	*	−1.2 to 0.1	ns
	Groundwater	<0.1 to 1.1	ns	<0.1 to 1.1	**	−0.1 to <0.1	ns	−0.2 to 0.1	a
	Streamwater	0.2	ns	0.1	ns	0.2	***	<0.1	ns
ANC μeq l−1 yearr−1	Soil water	1.7 to 9.5	***	4.1 to 6.7	*	4.6 to 6.3	***	−1.9 to 1.0	ns
	Groundwater	−18 to 4.4	**	3.9 to 7.6	**	−5.9 to 7.0	**	−4.5 to 0.9	a
	Streamwater	3.6	**	2.2	ns	4.7	***	1.9	**
IS mmol l−1 year−1	Soil water	−0.034 to −0.008	***	−0.009 to −0.002	ns	−0.021 to −0.018	***	−0.003 to 0.001	ns
	Groundwater	−0.029 to −0.007	***	−0.025 to 0.001	ns	−0.008 to −0.001	a	−0.002 to −0.001	a
	Streamwater	−0.013	***	−0.008	ns	−0.010	***	<0.001	ns

1998–2009 for Gammtratten

ns non-significant, nm non-monotonic

^aToo few observations for statistically reliable results

* P < 0.05, ** P < 0.01, *** P < 0.001