Table 1 Mean and standard deviation values of physical and chemical variables analysed during the study period in Zacarés rice fields

A

5

3

2,376 ± 34

1.2 ± 0.0

93.5 ± 29.4

25.8 ± 0.6

8.2 ± 0.7

296 ± 33

0.65 ± 0.20

0.06 ± 0.00

31.5 ± 2.8

0.12 ± 0.47

1.70 ± 0.18

B

6

4

2,906 ± 402

1.5 ± 0.2

138.2 ± 23.2

29.8 ± 2.6

8.8 ± 0.5

436 ± 70

0.38 ± 0.15

0.00 ± 0.00

33.7 ± 11.0

0.05 ± 0.04

0.58 ± 0.10

C

4

4

1,980 ± 184

1.0 ± 0.1

94.3 ± 42.1

27.8 ± 3.5

8.3 ± 0.1

209 ± 31

0.82 ± 0.26

0.00 ± 0.00

38.3 ± 12.5

0.71 ± 1.12

0.35 ± 0.13

D

4

4

2,503 ± 749

1.3 ± 0.4

112.5 ± 13.6

30.6 ± 2.3

8.7 ± 0.5

316 ± 70

0.64 ± 0.44

0.10 ± 0.20

33.7 ± 11.0

0.03 ± 0.00

0.35 ± 0.19

E

3

3

1,631 ± 218

0.8 ± 0.1

109.3 ± 50.9

29.8 ± 3.7

8.6 ± 0.2

152 ± 60

0.99 ± 0.02

0.00 ± 0.00

28.3 ± 14.1

0.33 ± 0.27

0.27 ± 1.27

F

4

3

2,610 ± 337

1.3 ± 0.2

128.6 ± 57.2

29.0 ± 1.4

8.5 ± 0.4

331 ± 61

0.48 ± 0.17

0.17 ± 0.14

25.0 ± 8.6

0.11 ± 0.12

0.97 ± 0.90

G

3

2

3,393 ± 1,034

1.8 ± 0.5

89.6 ± 33.5

29.9 ± 2.0

8.2 ± 0.2

448 ± 200

0.47 ± 0.40

0.17 ± 0.00

26.6 ± 11.5

0.19 ± 0.03

0.77 ± 0.12

H

2

1

1,845 ± 50

0.9 ± 0.0

161.0 ± 24.7

29.1 ± 0.1

8.5 ± 0.1

177 ± 3

0.73 ± 0.21

0.07 ± 0.07

30.0 ± 0.0

0.78 ± 0.18

0.05 ± 0.00

I

6

2

2,376 ± 410

1.2 ± 0.2

93.5 ± 23.5

25.8 ± 0.6

8.2 ± 0.3

296 ± 58

0.65 ± 0.19

0.06 ± 0.14

31.5 ± 12.8

0.12 ± 0.04

1.70 ± 0.29

J

4

3

2,506 ± 548

1.2 ± 0.3

83.7 ± 30.6

25.4 ± 1.0

8.3 ± 0.2

344 ± 141

0.53 ± 0.43

0.00 ± 0.00

33.0 ± 4.6

0.03 ± 0.04

0.53 ± 0.40