Table 5.1  Goshen Swamp water quality parameters one year before and one year after clearcut in June 1998; n=12 in both periods.

Before

After

parameter

mean

st dev

range

mean

st dev

range

temperature (oC)

16.7

5.3

10.1 - 26.3

17.3

7.7

2.8 - 26.8

pH

6.5

0.3

5.7 - 7.1

6.2*

0.4

5.8 - 6.9

specific conductivity (mS/cm)

153

57

70 -240

199*

62

100 - 280

total suspended solids (mg/L)

3

1.9

1 - 7

9.2

12.8

turbidity (NTU)

9.5

11.2

1.8 - 41.1

16.2

30.4

1.4 - 111.4

dissolved oxygen (mg/L)

6.3

2.9

1.7 - 10.5

5.1

4

0.0 - 12.6

fecal coliforms (colonies/100 mL)

118

100

9 - 330

2148

6698

11 - 23400

chlorophyll a (mg/L)

4.6

8.1

0.5 - 29.6

22.5

49.5

0.5 - 166.3

total phosphorus (mg P/L)

113

74

10 - 300

238

209

40 - 700

phosphate (mg P/L)

32

15

5 - 61

66

81

16 - 293

total nitrogen (mg N/L)

1425

366

920 - 1900

1525

1004

560 - 3460

total kjeldahl nitrogen (mg N/L)

1116

456

680 - 1800

1464

1047

440 - 3460

nitrate (mg N/L)

309

387

20 - 1220

64*

151

5 - 530

ammonia (mg N/L)

61

53

5 - 190

208*

283

20 - 960

* indicates significant difference (p<0.05) between before and after means