124
A. Solarczyk
Table 6.1 Basic statistics of annual average values of selected quality indicators of Polish river
waters examined in 2010–2015 (own calculations according to data of Voivodeship Inspectorates
for Environmental Protection)
Indicator Unit
Number Min.
Max.
Median Mean
95th
percentile
SEC
(20 °C)
µS/cm
2,362
46
33,249
476
636
1,119
Total
hardness
mgCaCO 3 /L 2,296
5.2
3,598
235
257
449
BOD 5
mgO 2 /L
2,383
0.4
58.4
2.5
3.0
5.6
TOC
mgC/L
2,353
0.3
88.1
8.8
9.5
18.3
TP
mgP/L
2,374
0.008
5.350
0.160
0.222
0.560
TN
mgN/L
2,371
0.09
38.25
2.63
3.43
8.65
Fig. 6.1 Spatial diversity of average specific electrical conductivity (µS/cm) in Polish river catchments and subcatchments in the years 2010–2015 (own elaboration based on the data of Voivodeship Inspectorates for Environmental Protection). Explanations: catchments and subcatchments
numbered as in Tables 6.2, 6.3, and 6.4