water and carbon -river exe case study (linking the river exe to water and carbon cycle)

Question 1

how does the river exe link to the carbon cycle?

Answer 1

.the very upper catchment of the river exe is moorland with large amounts of peat bogs -peat should be a carbon sink as dead organic matter is compacted in saturated conditions and is therefore unable to decompose due to the anaerobic conditions

Question 2

.how does the digging of drainage ditches effect the carbon cycle?

Answer 2

the digging of drainage ditches, means the dried peat is more succestible to erosion so the carbon contained within it dissolves in the water and gets transported downstream
.also means that carbon is no longer being sequestered in peatlands but is free to exchange from water to the atmosphere and become atmospheric carbon

Question 3

what does the digging of drainage ditches mean for the carbon cycle?

Answer 3

.it means that digging drainage ditches can therefore turn moorland peat from a sink to a source of carbon

Question 4

how does the river exe link to the water cycle?

Answer 4

.digging drainage ditches dries peat out and made it more sustainable for sheep farming however it also meant that water entered the river more quickly (as surface runoff), reducing lag time and increasing flood risk downstream

Question 5

what does the digging of drainage ditches mean for water quality?

Answer 5

.dissolved organic carbon makes water brown and therefore water companies have to remove the brown colour