case study - Sunderbans Flashcards
location and background
- SW Bangladesh and East India
- a delta in the Bay of Bengal
- part of largest mangrove forest in the world
- home to over 4 million
- flat and low lying
- intersected by many channels
- in dynamic equilibrium - rivers deposit sediment, growing mangrove and is also being eroded by the sea
what is a mangrove forest?
forest in tropical areas
trees adapted to living in salty water and grow on mudflats
goods provided by Sunderbans
timber - construction, firewood
rich ecosystem gives food - fish, crabs, honey
flat, fertile land in river delta - growing crops such as rice
services provided by Sunderbans
natural defence - absorbs energy and water
- protects against coastal flooding
- erosion, roots bind soil
- storms and cyclones
makes it easier to live and grow crops
tourism opportunities - attracted by wildlife and mangroves
carbon sink
- absorbs 4 billion tonnes a year
risks
coastal flooding
- salinisation of soil, more salty, harder to grow crops
- contamination of groundwater supplies
cyclones
- impact people and infrastructure
- mangroves absorb energy from storms, reducing their impact on people
erosion
- mangroves protect people
- tree roots hold soil together
mangroves protect against these risks
but are being destroyed due to increasing populations
- more need for fuel and space
- mangroves destroyed
reduced protection from risks
energy and water not absorbed
risks increasing
- climate change
- eustatic sea level rise
make risks more likely
exploitation of resources due to growing population
mangroves to agricultural land
how do they respond to risks?
resilience - being able to cope with challenges the environment presents
mitigation - reducing the severity of hazards and other issues
adaptation - adjusting behaviour to fit the environment
(more now due to climate change)
resilience
Public Health Engineering Department
increasing access to clean water and sanitation
- improve health and quality of life
NGOs offering training of more suitable methods of fishing and farming - more sustainable
- prevent environmental damage and exploitation
improving access
- building roads and bridges
but leads to deforestation and environmental damage
farming subsides
- efforts to decrease poverty
- improve food security and jobs available
mitigation
3500km of embankments
- prevent flooding, protect people
but being eroded, 800km vulnerable to being breached in storms
coastal management project
- protect mangroves
- replant lost areas
increase protection against flooding and erosion
but hard to stop illegal deforestation
(sea level rise making it harder)
mitigate impacts of hazards
NGOs provide funding for
- cyclone shelters
- warning systems
help protect people from storms and floods
adaptation
salt resistant crops grown
- survive flooding and sea level rise
- allows residents to maintain food and jobs
but reduces biodiversity
increasing tourism
- provides jobs and income
- eg boat trips
but environmental damage if not managed
adapting to sea level rise
- houses on stilts
but roads hard to protect
sustainable adaptations
- ecotourism
- sustainable farming
reducing damage to environment
future
challenge and risks increasing
due to climate change and sea level rise
mitigation and resilience may be insufficient
natural processes involved in creation of the landscape
deposition
tides
winds
vegetation succession
role of deposition
created many islands in river = network of connected channels
carry and deposit sediment when energy lost in Bay of Bengal
role of tides
delta flooded by high tides - 2x a day
= larger channels running north to south
role of winds
creates sand dunes inland
role of vegetation succession
sediment builds up to create mudflats
develops into mangrove by succession
colonised by pioneers etc
mangrove trees help to further stabilise ground
also occurs on sand dunes further inland
