clad oct09 igrieve (nx_power_lite)

Peatland disturbance & DOC fluxes: Braes of Doune, a

case study

Braes of Doune Windfarm

• Completed late 2006

• 400 ha site, 36 x 2 MW turbines, 20 km new roads

• Within River Teith Special Area of Conservation

• Altitude 370-540 m

• Mean annual precipitation 1600 mm

• Blanket peat soils

Disturbance: Pylons

Disturbance: Roads & Drains

Disturbance: Redistribution of peat

Mitigation??

Severie W

Annett

Severie E

Bheithe

Garvald

Criche

DateDist.

29/09/200813/02/200809/11/200709/10/200717/09/200707/09/200710/07/200715/10/2006y esnoy esnoy esnoy esnoy esnoy esnoy esnoy esno

35

30

25

20

15

10

5

0

DO

C m

g/L

Dissolved Organic Carbon, disturbed & control streams

35302520151050

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.1

0.0

DOC mg/L

Abs

orba

nce

(400

nm

)

noyes

Disturbance

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 50 100 150 200 250 300

Time h

Stag

e m

Dist ur bedCo nt r o l

0

5

10

15

20

25

30

0 50 100 150 200 250 300

Time h

DO

C m

g/L

Dist ur bedCo nt r o l

Aqueous carbon fluxes

Conclusions

• Increased DOC in disturbed streams, but DOC losses small compared to potential C savings

• Annual DOC losses of 5 g m-2 may be significant in the context of blanket peat soils as a net carbon sink.

• Downstream impacts on water discoloration and light transmission, especially if coupled with elevated turbidity.

• But only one study!!