Source: https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-16-coastal-defences-soft-engineering

[Revision notes](https://senecalearning.com/en-gb/revision-notes.md) › [IGCSE](https://senecalearning.com/en-gb/revision-notes/igcse.md) › [Geography](https://senecalearning.com/en-gb/revision-notes/igcse/geography.md) › [Edexcel IGCSE](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse.md) › Coastal Defences: Soft Engineering

# Coastal Defences: Soft Engineering

Geography: Edexcel IGCSE, topic 1.2.16

## Which Soft Engineering Strategies Can Protect the Coast?

Soft engineering strategies artificially use the sea, physical and natural processes to protect coastal areas from flooding and erosion.  Beach nourishment, dune regeneration, and beach reprofiling are examples of soft engineering strategies.

### What is beach nourishment?

![What is beach nourishment?](https://image-v2.cdn.app.senecalearning.com/2018-05/35b2d18e-32fe-4141-848e-865f3ac52939/shutterstock_98105777.jpg)

- Beach nourishment involves adding more sand to a beach.
- The sand can be purchased or moved from another part of the beach. 
- Sand and shingle will naturally be pushed up against groynes and this sediment can be put back on other parts of the beaches.

### What is beach reprofiling?

![What is beach reprofiling?](https://image-v2.cdn.app.senecalearning.com/2019-01/4af6eaea-5b1e-424c-a82b-beec925d38b7/sandcastle-beach-.jpg)

- Beach reprofiling involves changing the make-up of sediment and sand on a beach to protect the coastline. 
- Creating wider beaches can slow waves and reduce the energy that waves have when they hit the shore. 
- Reprofiling and moving sand & shingle can damage the wildlife living amongst it.

### What is dune regeneration?

![What is dune regeneration?](https://image-v2.cdn.app.senecalearning.com/2018-04/3b0f5bc5-8ff4-4f3e-bbce-5714b57c285b/shutterstock_387111535.jpg)

- Dune regeneration focuses on improving and maintaining sand dunes. 
- Nourishing or planting plants can help to support the dunes and help them resist wind and absorb destructive waves' energy. 
- Again, planting lots of vegetation all the way up and down sand dunes can be expensive.

## Test yourself on Coastal Defences: Soft Engineering

- Which of the following is a soft engineering coastal defence strategy?
- What are the three methods of soft engineering coastal defences?

[Practise this topic for free](https://app.senecalearning.com/classroom/course/ef6d2f62-5eb8-4168-aaaf-48efdb77968e/section/b2a1aec5-f013-4e1d-aceb-2ce621fb557f/session)

- Previous topic: [1.2.15 Coastal Defences: Hard Engineering](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-15-coastal-defences-hard-engineering.md)
- Next topic: [1.2.17 Coastal Defences: Managed Retreat](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-17-coastal-defences-managed-retreat.md)

## Geography: Edexcel IGCSE contents

### 1 Physical Geography
- 1.1 River Environments
  - [1.1.1 Weathering](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-1-weathering.md)
  - [1.1.2 Mass Movement](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-2-mass-movement.md)
  - [1.1.3 Erosion](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-3-erosion.md)
  - [1.1.4 Transportation](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-4-transportation.md)
  - [1.1.5 Deposition](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-5-deposition.md)
  - [1.1.6 River Landforms: Waterfalls & Gorges](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-6-river-landforms-waterfalls-and-gorges.md)
  - [1.1.7 River Landforms: Interlocking Spurs](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-7-river-landforms-interlocking-spurs.md)
  - [1.1.8 River Landforms: Flood Plains](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-8-river-landforms-flood-plains.md)
  - [1.1.9 River Landforms: Point Bars](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-9-river-landforms-point-bars.md)
  - [1.1.10 River Landforms: Levees](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-10-river-landforms-levees.md)
  - [1.1.11 River Landforms: Meanders](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-11-river-landforms-meanders.md)
  - [1.1.12 River Landforms: Oxbow Lakes](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-12-river-landforms-oxbow-lakes.md)
  - [1.1.13 River Landscape Changes: Long Profile](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-13-river-landscape-changes-long-profile.md)
  - [1.1.14 River Landscape Changes: Cross Profile](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-14-river-landscape-changes-cross-profile.md)
  - [1.1.15 Vertical & Lateral Erosion](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-15-vertical-and-lateral-erosion.md)
  - [1.1.16 Flood Risk Factors](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-16-flood-risk-factors.md)
  - [1.1.17 Human Activities on Rivers](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-17-human-activities-on-rivers.md)
  - [1.1.18 River Management: Hard Engineering](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-18-river-management-hard-engineering.md)
  - [1.1.19 River Management: Soft Engineering](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-19-river-management-soft-engineering.md)
  - [1.1.20 Case Study: The River Eden - Landforms](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-20-case-study-the-river-eden-landforms.md)
  - [1.1.21 Case Study: The River Eden - Climate](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-21-case-study-the-river-eden-climate.md)
  - [1.1.22 Case Study: The River Eden - Geology](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-22-case-study-the-river-eden-geology.md)
  - [1.1.23 Case Study: The River Eden - Management](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-23-case-study-the-river-eden-management.md)
  - [1.1.24 Case Study: The River Eden - Human Activity](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-24-case-study-the-river-eden-human-activity.md)
  - [1.1.25 End of Topic Test - River Environments](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-1-25-end-of-topic-test-river-environments.md)
- 1.2 Coastal Environments
  - [1.2.1 Weathering](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-1-weathering.md)
  - [1.2.2 Mass Movement](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-2-mass-movement.md)
  - [1.2.3 Erosion](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-3-erosion.md)
  - [1.2.4 Deposition](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-4-deposition.md)
  - [1.2.5 Longshore Drift](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-5-longshore-drift.md)
  - [1.2.6 Sediment Transportation](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-6-sediment-transportation.md)
  - [1.2.7 Wave Action on Coasts](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-7-wave-action-on-coasts.md)
  - [1.2.8 Other Factors Influencing Coasts](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-8-other-factors-influencing-coasts.md)
  - [1.2.9 Coastal Landforms: Wave-cut Platforms & Cliffs](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-9-coastal-landforms-wave-cut-platforms-and-cliffs.md)
  - [1.2.10 Coastal Landforms: Headlands & Bays](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-10-coastal-landforms-headlands-and-bays.md)
  - [1.2.11 Coastal Landforms: Caves, Arches & Stacks](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-11-coastal-landforms-caves-arches-and-stacks.md)
  - [1.2.12 Coastal Deposition](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-12-coastal-deposition.md)
  - [1.2.13 Spits, Bars & Sand Dunes](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-13-spits-bars-and-sand-dunes.md)
  - [1.2.14 Human Activity on Coasts](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-14-human-activity-on-coasts.md)
  - [1.2.15 Coastal Defences: Hard Engineering](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-15-coastal-defences-hard-engineering.md)
  - [1.2.16 Coastal Defences: Soft Engineering](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-16-coastal-defences-soft-engineering.md)
  - [1.2.17 Coastal Defences: Managed Retreat](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-17-coastal-defences-managed-retreat.md)
  - [1.2.18 Case Study: Holderness Coast Overview](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-18-case-study-holderness-coast-overview.md)
  - [1.2.19 Case Study: Holderness Coast Management](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-19-case-study-holderness-coast-management.md)
  - [1.2.20 Case Study: Holderness Coast Defences](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-20-case-study-holderness-coast-defences.md)
  - [1.2.21 End of Topic Test - Coastal Environments](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-2-21-end-of-topic-test-coastal-environments.md)
- 1.3 Hazardous Environments - Tropical Cyclones
  - [1.3.1 Characteristics of a Tropical Cyclone](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-3-1-characteristics-of-a-tropical-cyclone.md)
  - [1.3.2 Structure of a Tropical Cyclone](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-3-2-structure-of-a-tropical-cyclone.md)
  - [1.3.3 Physical Hazards of Tropical Cyclones](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-3-3-physical-hazards-of-tropical-cyclones.md)
  - [1.3.4 The Impacts of Tropical Cyclones](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-3-4-the-impacts-of-tropical-cyclones.md)
  - [1.3.5 Responses to Tropical Cyclones](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-3-5-responses-to-tropical-cyclones.md)
  - [1.3.6 Vulnerability to Tropical Cyclones](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-3-6-vulnerability-to-tropical-cyclones.md)
  - [1.3.7 Preparing for Tropical Cyclones](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-3-7-preparing-for-tropical-cyclones.md)
  - [1.3.8 Case Study: Katrina](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-3-8-case-study-katrina.md)
  - [1.3.9 Case Study: Nargis](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-3-9-case-study-nargis.md)
- 1.4 Hazardous Environments - Earthquakes & Volcanoes
  - [1.4.1 Earthquakes](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-4-1-earthquakes.md)
  - [1.4.2 Features of an Earthquake](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-4-2-features-of-an-earthquake.md)
  - [1.4.3 Types of Earthquake](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-4-3-types-of-earthquake.md)
  - [1.4.4 Case Study: L'Aquila](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-4-4-case-study-laquila.md)
  - [1.4.5 Case Study: Chile](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-4-5-case-study-chile.md)
  - [1.4.6 Case Study: Japan & Pakistan - Planning](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-4-6-case-study-japan-and-pakistan-planning.md)
  - [1.4.7 Volcanoes](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-4-7-volcanoes.md)
  - [1.4.8 Types of Volcanoes](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-4-8-types-of-volcanoes.md)
  - [1.4.9 Volcanic Eruptions](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/1-4-9-volcanic-eruptions.md)

### 2 Human Geography
- 2.1 Economic Activity & Energy
  - [2.1.1 Increasing Energy Consumption](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/2-1-1-increasing-energy-consumption.md)
  - [2.1.2 Non-Renewable Energy - Nuclear](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/2-1-2-non-renewable-energy-nuclear.md)
  - [2.1.3 Non-Renewable Energy - Fossil Fuels](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/2-1-3-non-renewable-energy-fossil-fuels.md)
  - [2.1.4 Renewable Energy - Solar](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/2-1-4-renewable-energy-solar.md)
  - [2.1.5 Renewable Energy - Water & Bio](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/2-1-5-renewable-energy-water-and-bio.md)
  - [2.1.6 Renewable Energy - Hydro](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/2-1-6-renewable-energy-hydro.md)
  - [2.1.7 Energy - Statistical Skills](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/2-1-7-energy-statistical-skills.md)
- 2.2 Rural Environments
  - [2.2.1 Rainforests](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/2-2-1-rainforests.md)
  - [2.2.2 Temperate Forests](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/2-2-2-temperate-forests.md)
  - [2.2.3 Characteristics of a Temperate Forest](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/2-2-3-characteristics-of-a-temperate-forest.md)
  - [2.2.4 Goods & Services in Temperate Forests](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/2-2-4-goods-and-services-in-temperate-forests.md)
  - [2.2.5 Deserts](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/2-2-5-deserts.md)
  - [2.2.6 Tundra](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/2-2-6-tundra.md)
- 2.3 Urban Environments
  - [2.3.1 Urbanisation in Different Countries](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/2-3-1-urbanisation-in-different-countries.md)
  - [2.3.2 Causes of Urbanisation](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/2-3-2-causes-of-urbanisation.md)
  - [2.3.3 Consequences of Urbanisation](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/2-3-3-consequences-of-urbanisation.md)
  - [2.3.4 Sustainable Urbanisation](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/2-3-4-sustainable-urbanisation.md)
  - [2.3.5 Case Study: Rapid Urbanisation in Mexico City](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/2-3-5-case-study-rapid-urbanisation-in-mexico-city.md)
  - [2.3.6 End of Topic Test - Urbanisation](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/2-3-6-end-of-topic-test-urbanisation.md)

### 3 Global Issues
- 3.1 Fragile Environments & Climate Change
  - [3.1.1 Natural Causes of Climate Change](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-1-1-natural-causes-of-climate-change.md)
  - [3.1.2 Effects of Climate Change on the Environment](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-1-2-effects-of-climate-change-on-the-environment.md)
  - [3.1.3 Effects of Climate Change on People](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-1-3-effects-of-climate-change-on-people.md)
  - [3.1.4 Impacts of Deforestation](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-1-4-impacts-of-deforestation.md)
  - [3.1.5 End of Topic Test - Climate Change](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-1-5-end-of-topic-test-climate-change.md)
  - [3.1.6 Increasing Water Supply](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-1-6-increasing-water-supply.md)
  - [3.1.7 Sustainable Rainforest Management](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-1-7-sustainable-rainforest-management.md)
- 3.2 Globalisation & Migration
  - [3.2.1 Globalisation - Transport](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-2-1-globalisation-transport.md)
  - [3.2.2 Globalisation - Communication Networks & Banking](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-2-2-globalisation-communication-networks-and-banking.md)
  - [3.2.3 Push & Pull Factors](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-2-3-push-and-pull-factors.md)
  - [3.2.4 TNCs & Globalisation](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-2-4-tncs-and-globalisation.md)
  - [3.2.5 Tourism Landscapes](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-2-5-tourism-landscapes.md)
  - [3.2.6 The Growth of Tourism](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-2-6-the-growth-of-tourism.md)
  - [3.2.7 The Economic Benefits of Tourism](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-2-7-the-economic-benefits-of-tourism.md)
  - [3.2.8 The Social & Cultural Benefits of Tourism](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-2-8-the-social-and-cultural-benefits-of-tourism.md)
  - [3.2.9 The Economic Costs of Tourism](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-2-9-the-economic-costs-of-tourism.md)
  - [3.2.10 The Social & Cultural Costs of Tourism](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-2-10-the-social-and-cultural-costs-of-tourism.md)
  - [3.2.11 Managing Tourism - Sustainability](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-2-11-managing-tourism-sustainability.md)
  - [3.2.12 Managing Tourism - Quotas & Tourism Hubs](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-2-12-managing-tourism-quotas-and-tourism-hubs.md)
- 3.3 Development & Human Welfare
  - [3.3.1 Ways of Defining Development](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-3-1-ways-of-defining-development.md)
  - [3.3.2 Different Ways of Measuring Development](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-3-2-different-ways-of-measuring-development.md)
  - [3.3.3 Environmental Factors Causing Uneven Development](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-3-3-environmental-factors-causing-uneven-development.md)
  - [3.3.4 Historical Factors Causing Uneven Development](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-3-4-historical-factors-causing-uneven-development.md)
  - [3.3.5 Economic Factors Causing Uneven Development](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-3-5-economic-factors-causing-uneven-development.md)
  - [3.3.6 Patterns of Development](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-3-6-patterns-of-development.md)
  - [3.3.7 How Can we Reduce the Global Development Gap?](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-3-7-how-can-we-reduce-the-global-development-gap.md)
  - [3.3.8 Top-Down & Bottom-Up Development](https://senecalearning.com/en-gb/revision-notes/igcse/geography/edexcel-igcse/3-3-8-top-down-and-bottom-up-development.md)
