1
Q
Rock Type
A
upper course of Ribble is Millstone Grit with few pore spaces and therefore increased overland flow
2
Q
soil
A
peat in the upper course is a major source of groundwater, slowing down increase in discharge
3
Q
shape and size of drainage basin
A
- elongated basin = water taking more time to reach channel
- basin is very big, extensive floodplains
4
Q
rainfall
A
- rainfall is evenly distributed around year
- infiltration excess -> overland flow following summer thunderstorms
- saturation so excess flooding common at end of winter
5
Q
urbanisation
A
- tributary calder runs through Burnley suburb, with rapid discharge as water is directed into river
6
Q
agriculture
A
in the lower Ribble, overstocking w sheep has led to vegetation degrading = increased soil erosion
- peat cover has been lost due to fire
