Unintentional

Question 1

unintentioanl facts

Answer 1

Mangawhai - Pakiri
East coast of Northern Peninsula NZ.
Sand used from offshore, for construction and glass and soft engineering techniques such as beach nourishment
Dredging used to obtain sediment
Sediment budget closed system → nearshore mining of sediment not replaced by waves offshore
Extraction rates 5 times faster
Beaches wider and flatter, less good at absorbing wave energy
Dunes and spits become vulnerable
Loss of vegetation → wind erosion
Disturbed equilibrium. Coastal retreat

Holderness Coast
River Humber port, trade, construction of port led to disruption of sediment cell
Reduced input of coastal sediment from erosion
Hornsea Groynes → TGS
Repeated with M, A W and E.
Sea wall at Hornsea reduce wave energy at obstruc movement of sediment
Off shore dredging for help of construction of power plant at Easington can lead to sediment imbalance off-shore
Construction of ^^^ also lead to imbalance → + coastal erosion so retreat
1 million m3 of sediment results from cliff erosion and 2 million m3 from the erosion→ inc rate of erosion due to human activity
Unbalanced equilibrium → self regulation

-the effect of these impacts in changing coastal landforms, such as beach profiles

Question 2

New Zealand, Mangawhai, Pakiri

Answer 2

The coastal sediment budget is a closed system and therefore the outputs of sand through nearshore mining are not replenished by inputs from rivers and waves from offshore. Extraction rates are five times more than the input rates. Mining depletes the stores of sand in dunes, beaches and on the sea bed 2km offshore. Movements of sand between the major stores have reduced as a consequence. Current rates of extraction are unsustainable for the sediment cell.

Question 3

holderness coast

Answer 3

The trade port and dredging lead to an imbalance of sediment onshore to offshore. This meant that coastal retreat occurred along the sediment cell and undergoing self regulation in order to combat this. Furthermore, the materials will also have changed as the sediment in the sea will now be on the beach