2.4 Interrelationships between the natural environment and human activities

syllabus_link_buttonDemonstrate an understanding that the natural environment presents hazards and offers opportunities for human activities. Reference should be made to the hazards posed by volcanic eruptions, earthquakes, tropical storms, flooding and drought.

The natural environment has shaped human history and influences all aspects of life (settlement location, food and water supplies, types of industry and population size).  Nature has provides countless opportunities for human development but also poses many risks.

Floodplains & Deltas

Floodplains exist due to the natural deposition of fertile silt when rivers flood in the lower course.  They have provided excellent farming opportunities for populations due to the rich flat soils.  In addition to the soil, they have a reliable freshwater source in the form of the river that can provide water for irrigation of crops.

The Eastern lowlands of Costa Rica are used for extensive banana plantations.

Increasing populations and the desire to live in locations that have pleasant views have led to the building of homes on many floodplain areas.  This change in the use of floodplains is posing significant challenges as increasingly floods affect more and more properties and cause increasing economic damage.

The 2014 Winter flooding of Sommerset, UK which lasted for over a month highlighted the inability of humans to control natural processes.  Changing weather patterns and the impact on natural drainage processes due to urbanisation are leading to more frequent major flood incidents.

Volcanic Landscapes

The slopes of volcanoes offer rich fertile soils created by the ejection of mineral and nutrient rich ash and lava from volcanic eruptions.  Agriculture is often found on volcanic slopes and they benefit from reliable water sources as water vapour in the rising air condenses bringing clouds and rain. Pineapples,strawberries and coffee are grown on the slopes around Poas volcano in Costa Rica.

Volcanoes provide many other economic opportunities.  Sulphur is mined from Indonesian volcanoes which is found around the vent areas. Tourism industries often surround volcanoes (hotels, tour guides, cafes etc) which attract many trekkers and adventurers.

Volcanic environments come with well-known risks though.  Earthquakes and the effects of eruptions (lava, pyroclastic and mud flows) can cause major damage and loss of life.  Even when the risks are understood and measures have been put in place to protect the local populations nature often continues to pose major hazards.

Tropical Storms

Tropical locations have attracted settlers and tourists throughout history due to the warm climate, reliable rainfall, fertile soils, resources and natural beauty.  Early colonial powers established plantations in many tropical regions to supply exotoc fruits, spices, nuts and vegetables. Tropical beaches, coral reefs and rainforest have led to the emergence of major tourism infrastructure and generate significant sums of money.

These productive environments often pose many hazards such as disease (malaria, yellow fever) and tropical storms/hurricanes.  Despite huge advances in forecasting the formation of major storms and the likely path that they will travel humans are still highly vulnerable tp their effects.  The strength of the winds often damage buildings and infrastructure and the volume of water floods farmland and urban areas.

Hurricane Katrina highlighted the ability of nature to overwhelm even the most economically powerfull country in the world.  When it hit New Orleans in 2005 it caused major flooding and damage, dsiplacing tens of thousands of people from their homes.  Evacuation procedures were poor and emergency services struggled to find and rescue people.  The defences against such a storm failed and left the city at the mercy of nature.

Human Impacts

Humans have had significant impacts on most of the natural environments in the world.  One of the major changes has been managing the vegetation, usually replacing the natural plants with crops for consumption or trees to supply industries.  Presently there is global conern over the rate of deforestation of tropical rainforest. These forests play an important role in removing carbon dioxide from the air (they store it as biomass) and recycling oxygen.  They are vitally inportant in regulation some of the climatic cycles of the atmosphere and are home to vast numbers of plant, insect, bird and animal species.

Major causes of deforestation include:

  • clearing the land for mining (fossil fuels and precious metals).
  • flooding rainforest for hydro-electric dams.
  • replacing rainforest with plantations of palm trees for palm oil.
  • logging to provide timber.