Appendix-Table 1: Spearman correlations of water parameters in the waters of the reservoir system, analyzed in biweekly values between May 2008 and September 2014

a) Spearman correlations of water parameters in Quergraben tributary

DOC / dis-charge / NO3- / As total / As diss. / P total / turbi-dity / Fe / water T / SO42-
DOC / 1
discharge / .830** / 1
NO3- / n.s. / n.s. / 1
As total / .631** / .415** / -.499** / 1
As dissolved / .698** / .487** / -.401** / .937** / 1
P total / .602** / .384** / -.537** / .645** / .583** / 1
turbidity / .404** / n.s. / -.242* / .428** / .359** / .545** / 1
Fe / .614** / .356** / -.391** / .543** / .587** / .648** / .429** / 1
water T / -.262* / -.440** / -.650** / n.s. / n.s. / n.s. / n.s. / n.s. / 1
SO42- / -.245* / n.s. / .288* / -.547** / -.524** / -.509** / -.409** / -.382** / -.395** / 1
pH / -.592** / -.805** / -.326** / n.s. / n.s. / n.s. / n.s. / n.s. / .630** / n.s.

b) Spearman correlations of water parameters in Neugraben tributary

DOC / dis-charge / NO3- / As total / As diss. / P total / turbi-dity / Fe / water T / SO42-
DOC / 1
discharge / .801** / 1
NO3- / n.s. / .332** / 1
As total / n.s. / n.s. / -.501** / 1
As dissolved / .378** / .333** / -.259* / .730** / 1
P total / .527** / .330** / -.319** / .495** / .470** / 1
turbidity / n.s. / n.s. / n.s. / .331* / n.s. / .545** / 1
Fe / .771** / .570** / n.s. / n.s. / n.s. / .646** / .449** / 1
water T / n.s. / -.359** / -.792** / .551** / .432** / .332** / n.s. / n.s. / 1
SO42- / -.689** / -.525** / n.s. / -.402** / -.627** / -.553** / -.302* / -.470** / -.375** / 1
pH / -.547** / -.708** / -.543** / .360** / n.s. / n.s. / n.s. / -.539** / .608** / n.s.

c) Spearman correlations of water parameters in Galgenteich water (transfer flow to Altenberg reservoir)

DOC / NO3- / As total / As diss. / P total / turbi-dity / Fe / water T / SO42- / pH
DOC / 1
NO3- / n.s. / 1
As total / .258** / -.638** / 1
As dissolved / .336** / -.569** / .945** / 1
P total / .338** / -.606** / .888** / .869** / 1
turbidity / n.s. / -.413** / .484** / .457** / .489** / 1
Fe / .402** / -.277* / .761** / .729** / .663** / 0.13 / 1
water T / -.211* / -.502** / n.s. / n.s. / n.s. / .297** / -.388** / 1
SO42- / -.608** / n.s. / n.s. / -.360** / -.354** / n.s. / n.s. / -.338** / 1
pH / -.275** / -.532** / .476** / .435** / .415** / .361** / n.s. / .351** / n.s. / 1

d) Spearman correlations of water parameters in Altenberg reservoir water, depth profile 12.5m deep

DOC / NO3- / As total / As diss. / P total / turbi-dity / Fe / water T / SO42- / pH
DOC / 1
NO3- / 0.233 / 1
As total / -.257** / -.597** / 1
As dissolved / -.257** / -.528** / .957** / 1
PO4 total / n.s. / -.369** / .484** / .478** / 1
turbidity / .271** / n.s. / n.s. / n.s. / n.s. / 1
Fe / .197* / -.389** / .448** / .431** / .587** / .223* / 1
water T / -.317** / n.s. / .409** / .455** / n.s. / -.377** / -.284** / 1
SO42- / -.399** / n.s. / n.s. / n.s. / n.s. / n.s. / n.s. / n.s. / 1
pH / n.s. / -.317** / .235** / .176* / .335** / .479** / .421** / -.235** / -.276* / 1
O2 / n.s. / n.s. / n.s. / n.s. / .334** / .406** / .313** / -.603** / n.s. / .541**

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