CHAT Flashcards
Explain how coastal landscapes can be viewd as systems (8 marks)
Inputs:
. Coastal systems receive inputs both from the land and sea
Processes:
. Within coastal systems numerous processes operate simultaneously
Stores:
. Coastal landscapes consist of various components or stores that store and transfer energy and materials
Outputs:
. Coastal systems produce outputs in the form of sediment transport, nutrient cycling, and energy dissipation
Feedback
To what extent are long term changes more
influential on coastal landscape systems than short term changes?
Long term:
Geological processes
Sedimentation patterns
Climate change
Ecological succession
Short term:
Storm events
Seasonal variability
Human activities
Extreme events
Inputs
Coastal systems receive various inputs from both the land and the sea. These inputs include sediment from rivers, nutrients from terrestrial runoff, energy from waves and currents, and atmospheric factors such as wind and precipitation
Stores and components
Coastal landscapes consist of various components or stores that store and transfer energy and materials. These components may include beaches, cliffs, dunes, estuaries, and coral reefs. Each of these components interacts with others within the system, influencing its overall behavior
Processes
Within coastal systems, numerous processes operate continuously. These processes include erosion, transportation, and deposition of sediment, as well as biological processes such as plant growth and animal activities. Additionally, physical processes like wave action, tides, and longshore currents play significant roles in shaping coastal landforms
Outputs
Coastal systems produce outputs in the form of sediment transport, nutrient cycling, and energy dissipation. Sediment may be exported to offshore areas or accumulate within the system, influencing its morphology over time. Nutrients may be released into the water column, affecting biological productivity, while energy may be dissipated through wave breaking and frictional losses
Feedback
Feedback mechanisms play a crucial role in regulating coastal systems. Positive feedback loops, such as beach erosion leading to increased wave energy, can amplify system changes. Conversely, negative feedback loops, like vegetation growth stabilizing dunes, help to maintain system equilibrium by counteracting disturbances.
Geological processes
Long-term changes, such as tectonic activity and sea level changes over millennia, profoundly shape coastal landscapes. Tectonic movements can uplift or subside coastlines, leading to the formation of features like coastal cliffs or raised beaches. Similarly, fluctuations in sea levels over geological timeframes can result in the creation of coastal landforms like barrier islands and estuaries
Sedimentation patterns
The long-term accumulation and redistribution of sediment significantly influence coastal morphology. Processes like erosion and deposition shape coastlines over centuries, with sediment transport driven by factors like ocean currents, wind patterns, and geological structures. Over time, these processes can lead to the formation of extensive coastal features such as spits, deltas, and coastal plains
Climate change
Long-term shifts in climate, including changes in temperature, precipitation patterns, and sea level rise, have profound effects on coastal landscapes. Rising sea levels, for example, can result in increased coastal erosion, inundation of low-lying areas, and changes in shoreline configuration over centuries
Ecological succession
Long-term changes in vegetation and ecological succession influence coastal ecosystems and landforms. Over decades to centuries, plant colonization, growth, and decay contribute to the stabilization of coastal dunes, marshes, and other landforms, affecting sediment dynamics and ecosystem services
Storm events
Short-term events such as storms, hurricanes, and tsunamis can exert rapid and significant impacts on coastal landscapes. These events can cause erosion, sediment transport, and deposition in a matter of hours to days, reshaping coastlines and altering coastal morphology temporarily
Seasonal variability
Short-term changes associated with seasonal variations in weather patterns, tides, and wave energy influence coastal processes. For example, winter storms may lead to increased erosion and sediment transport along coastlines, while calmer summer conditions may promote sediment deposition and beach accretion
Human activity
Anthropogenic activities, including coastal development, dredging, and beach nourishment, can induce rapid changes in coastal landscapes over short timeframes. Construction of coastal structures, extraction of resources, and alteration of natural drainage patterns can alter sediment dynamics, erosion rates, and ecosystem functioning in relatively short periods
Extreme events
Short-term extreme events, such as storm surges and king tides, can exacerbate coastal hazards and accelerate erosion rates. While these events may have immediate impacts, their longer-term effects depend on factors such as sediment availability, coastal management strategies, and natural recovery processes.
