Appendix

Table 1: Summary of macroinvertebrate species richness data sets used in the meta-analyses.

Aciditya / Regionb / Length of pH gradient / MeanpH / n / Slope / Variance / Reference
A / CDN / 2.4 / 6.8 / 20 / -0.26 / 6.55 / Clarke & Scruton 1997
A / CDN / 1.9 / 5.4 / 8 / 8.23 / 3.55 / Mackay & Kersey 1985c
A / D / 3.8 / 5.8 / 41 / 7.06 / 1.35 / Braukmann 2001
A / DK / 3.2 / 6.4 / 6 / 1.48 / 0.32 / Friberg 1997
A / DK / 3.0 / 5.8 / 4 / 4.80 / 0.04 / Thomsen & Friberg 2002
A / F / 2.5 / 5.7 / 20 / 13.27 / 1.97 / Dangles & Guérold 1999
A / F / 2.3 / 5.9 / 8 / 8.22 / 3.96 / Guerold 2000
A / F / 2.8 / 5.9 / 28 / 13.08 / 2.59 / Guerold et al. 1993
A / F / 3.0 / 5.8 / 41 / 16.19 / 1.87 / Guerold et al. 2000
A / F / 1.5 / 5.8 / 7 / 7.08 / 4.04 / Tixier & Guérold 2005d
A / P / 1.9 / 6.4 / 8 / -6.94 / 7.18 / Graça et al. 2004
A / S / 1.2 / 5.7 / 13 / 19.91 / 23.47 / Otto & Svensson 1983
A / S / 2.7 / 5.9 / 11 / 6.54 / 4.08 / Petrin et al.unpublished
A / S / 2.6 / 5.4 / 111 / 2.04 / 0.10 / Petrin et al. 2007a
A / GB / 3.6 / 5.7 / 6 / 11.11 / 26.39 / Armitage 1980e
A / GB / 2.4 / 5.3 / 9 / 4.80 / 8.05 / Harriman & Morrison 1982
A / GB / 1.9 / 5.5 / 9 / 4.68 / 12.02 / Lancaster et al. 1996
A / GB / 1.8 / 6.2 / 17 / 7.94 / 3.33 / Soulsby et al. 1997
A / GB / 2.1 / 6.0 / 5 / 6.97 / 5.39 / Tipping et al. 2002
A / GB / 1.5 / 5.6 / 11 / 6.41 / 13.82 / Townsend et al. 1983
A / GB / 2.9 / 6.3 / 4 / 6.55 / 1.55 / Ventura & Harper 1996
A / USA / 3.4 / 5.7 / 4 / 1.84 / 0.11 / Courtney & Clements 1998f
A / USA / 1.5 / 6.5 / 6 / 7.13 / 0.89 / Feldman & Connor 1992
A / USA / 1.5 / 6.5 / 6 / 4.87 / 0.49 / Feldman & Connor 1992g
A / USA / 1.8 / 6.0 / 4 / 6.34 / 3.46 / Kimmel et al. 1996
A / USA / 1.9 / 5.5 / 4 / 3.84 / 2.60 / Mulholland et al. 1986h
A / USA / 1.9 / 5.5 / 4 / 16.65 / 13.51 / Rosemond et al. 1992
N / CR / 1.1 / 5.7 / 6 / -0.15 / 7.31 / Ramírez et al. 2006
N / FIN / 3.9 / 6.5 / 203 / 2.34 / 0.31 / Heino et al. 2003
N / IRL / 2.0 / 6.1 / 4 / 16.57 / 9.72 / Clenaghan et al. 1998
N / NZ / 2.9 / 6.1 / 4 / 5.54 / 5.03 / Collier & Winterbourn 1987b
N / NZ / 2.8 / 6.1 / 4 / 2.50 / 1.49 / Collier & Winterbourn 1987ai
N / NZ / 3.8 / 6.0 / 18 / 3.08 / 0.78 / Olsson et al. 2006
N / NZ / 3.1 / 5.3 / 4 / 0.31 / 0.32 / Tank & Winterbourn 1995
N / S / 2.5 / 5.3 / 6 / -1.78 / 2.94 / Dangles et al. 2004b
N / S / 2.6 / 5.6 / 10 / 4.09 / 10.58 / Petrin et al.unpublished
N / S / 3.2 / 5.5 / 360 / 1.29 / 0.02 / Petrin et al. 2007a
N / S / 2.2 / 5.1 / 12 / 0.06 / 0.76 / Petrin et al. 2007b
N / ZA / 1.4 / 6.4 / 4 / -2.64 / 1.72 / Kinvig & Samways 2000k

Note:mean pH, mean gradient pH; n, number of replicate streams; slope, effect size measure.

aA, anthropogenic; N, natural.

bBOL, Bolivia; CDN, Canada; CR, Costa Rica; D, Germany; DK, Denmark; F, France; FIN, Finland; GB, United Kingdom; IRL, Ireland; NZ, New Zealand; P, Portugal; S, Sweden; USA, United States; ZA, South Africa.

cEphemeroptera-Plecoptera-Trichoptera genera.

dAdult Plecoptera.

eMine drainage caused acidity.

fExperimental acidification.

gEphemeroptera.

hGrazers.

iLeaf packs.

kOdonata.

Table 2: Summary of ecological functioning data sets used in the meta-analyses.

Mesha / Acidityb / Regionc / Length of pH gradient / Mean pH / n / Slope / Variance / Reference
fine / A / CDN / 3.0 / 6.0 / 6 / 2.89E-04 / 1.75E-08 / Mackay & Kersey 1985d,m
fine / A / F / 2.6 / 5.9 / 7 / 2.44E-05 / 6.54E-10 / Dangles & Guérold 2001e,n,v
fine / A / S / 2.7 / 5.9 / 11 / 5.25E-04 / 1.46E-06 / Petrin et al.unpublishedf,o
fine / A / GB / 1.9 / 5.9 / 7 / 9.83E-04 / 2.36E-07 / Chamier 1987g
fine / A / GB / 1.9 / 5.9 / 7 / 5.86E-03 / 9.76E-07 / Chamier 1987f
fine / A / GB / 1.9 / 5.9 / 7 / 5.71E-04 / 4.55E-08 / Chamier 1987h
fine / N / NZ / 2.9 / 6.1 / 4 / 2.36E-04 / 1.82E-08 / Collier et al. 2006i,m
fine / N / S / 2.5 / 5.3 / 6 / 3.78E-04 / 5.86E-08 / Dangles et al. 2004bk,n
fine / N / S / 2.6 / 5.6 / 10 / 3.55E-04 / 6.62E-07 / Petrin et al.unpublishedk,o
fine / N / S / 2.1 / 5.0 / 11 / 1.17E-04 / 9.26E-08 / Petrin et al. 2007bf,k,o
coarse / A / CDN / 3.0 / 6.0 / 6 / 1.09E-03 / 7.84E-08 / Mackay & Kersey 1985d,p
coarse / A / F / 2.2 / 6.0 / 7 / 3.62E-03 / 1.39E-07 / Dangles et al. 2004ae,p
coarse / A / S / 2.7 / 5.9 / 11 / 5.11E-04 / 9.14E-06 / Petrin et al. unpublishedf,r
coarse / A / USA / 3.2 / 5.9 / 4 / 5.47E-04 / 1.87E-07 / Griffith & Perry 1994d,s,v
coarse / A / USA / 3.2 / 5.9 / 4 / 2.90E-04 / 1.42E-07 / Griffith & Perry 1994l,t,v
coarse / A / USA / 1.9 / 5.4 / 4 / 1.12E-03 / 6.30E-08 / Mulholland et al. 1992d,t
coarse / A / USA / 1.4 / 5.4 / 5 / 2.35E-03 / 3.85E-06 / Mulholland et al. 1992d,t
coarse / N / NZ / 2.9 / 6.1 / 4 / 1.65E-03 / 1.79E-07 / Collier et al. 2006i,u
coarse / N / S / 2.5 / 5.3 / 6 / 2.24E-03 / 3.06E-05 / Dangles et al. 2004bk,p
coarse / N / S / 2.6 / 5.6 / 10 / -4.16E-04 / 1.64E-06 / Petrin et al. unpublishedk,r
coarse / N / S / 2.1 / 5.0 / 11 / 1.07E-02 / 5.55E-05 / Petrin et al. 2007bf,k,r

Note: mean pH, mean gradient pH; n, number of replicate streams; slope, effect size measure.

aMesh: decomposition in fine mesh bags is mainly mediated by microbes, that in coarse mesh bags by both microbes and macroinvertebrates.

bA, anthropogenic; N, natural.

cCDN, Canada; F, France; GB, United Kingdom; NZ, New Zealand; S, Sweden; USA, United States.

dLeaf species: Acer saccharum.

eLeaf species: Fagus sylvatica.

fLeaf species: Alnus glutinosa.

gLeaf species: Nardus stricta.

hLeaf species: Quercus robur.

iLeaf species: Weinmannia racemosa.

kLeaf species: Alnus incana.

lLeaf species: Quercus alba.

mMesh: 0.2mm.

nMesh: 0.3mm.

oMesh: 0.5mm.

pMesh: 5mm.

rMesh: 10mm.

sMesh: 3mm.

tMesh: 4mm.

uMesh: 7mm.

vTemperature-corrected.

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