Geography 3.1 AS 90701 ANALYSE NATURAL PROCESSES IN THE CONTEXT OF A GEOGRAPHIC ENVIRONMENT

Natural Processes are related sequences of actions that create or modify natural features. Natural features are phenomena in a geographic environment that result from natural processes over time. Geographic environments are spatial areas which are classified by the dominant natural processes that operate within them eg volcanic environments and coastal environments.

biological fluvial climatic Main natural processes aeolian geologic soil glacial coastal

Putting these into processes into high order processes we see 3 major processes interacting. uplift energy from the earth cloud Rain/snow sediment evaporation decomposition Salt water biogeographical geomorphological new land transpiration Nutrient uptake new rock weathering hydrological erosion Ocean water

Systems Systems are dynamic Systems seek dynamic equilibrium Change in one part of a system may lead to change in other parts of the system Landscapes are the results of processes interacting within the environment Processes vary in time and space Processes vary in magnitude and frequency

Systems have 4 main components: inputs feedbacks processes outputs

For the coastal system identify the elements of each component. inputs processes outputs feedbacks

Processes are high order and low order Geomorphological Hydrological Climatological Biogeographical Pedological Crustal movement/Igneous activity/weathering/mass wasting/slope development Wave energy/wave erosion/wave refraction/weathering/longshore transportation/fluvial action Aeolian action/land and sea level change Erosion and deposition of landforms Beach sorting/beach slope development

Look at the features that follow and discuss the various factors that have been involved in its formation. Remember to think in geological time as well as current actions. Specific detail needs to be included to explain the feature.

Whakataki (north of Castlepoint) And next picture…

Castlepoint

Raised terraces

Whatarangi Bluff

Cape Palliser

Putangirua Pinnacles

Turakirae Head

Beach

Cape Palliser Cape Palliser

Honeycombe Rock

Kupe’s Sail

Fan

Coastline types – sea level change Submerged steep terrain – river valleys (ria) Drowned glacial valleys – fiords Coastal plain Steep terrain Merging alluvial fans Volcanic

Coastline types – rock structure Atlantic – at 90 degrees to the coast (discordant), bays and headlands Pacific (Dalmation) – parallel to coast, straight with small bays

Coastal classification model After Valentin

Issues around the coast? Cost Protection Erosion Issues around the coast? Deposition Stabilisation Innundation

Uses of the coast Settlement – harbours, recreational centres Commercial – ports, industry, fishing Agriculture Reserves

Erosion management options Advantages Disadvantages No Action Minimum interference with the coast Political unpopular with residents Relocation Minimum interference with the coast Expensive. Politically unpopular with residents Seawall or revetment Reflects destructive wave energy away from coast, perceived as real protection Expensive, causes enhanced scour in front of wall Offshore breakwater Causes wave breaking and therefore energy dissipation, real protection Expensive, leads to possible changes to wave environment Groynes Prevents longshore rift, real protection Expensive, transfers problem down coast Beach nourishment Uses natural processes, doesn’t ruin natural character of beach Expensive, needs regular and appropriate replacement material

Pre Post

Perspectives of coastal management approaches Scientific, materialistic approach Maori spiritual approach Ownership and responsibility issues Compartmentalisation Holistic Let nature take its course Law and legislation