Months (2009-2010 monthly average values)

pH

Water temperature (˚C)

Oxygen (mg∙l−1)

Light porous effect (m)

April

8.14

13.6

9.48

7

May

8.5

17.2

9.36

6.1

June

7.76

19.8

8.62

7.7

July

7.84

22.2

8.04

8.9

August

8.12

23

8.28

9.6

September

8.16

18.4

8.36

7.1

October

8.8

14.5

8.7

6.6

November

8.24

9.7

9.9

7.6

December

8.04

5.2

9.72

8.6

January

7.8

4

10.6

10.8

February

7.8

4.4

11.2

9.2

March

8.04

10.4

9.06

7