Environmental impact of humans activities

• Environmental impact of human activities

  Ways in which humans can affect and change environments
• Exploiting natural resources

  • Environments far from human habitation, that have no resources worthy of exploitation, are relatively untouched by humans
  • Environments that have resources are often exploited to the extent that few plant and animal populations remain
• Genetically modified (GM) crops

  May produce higher food crop yields, but scientists believe they may also create environmental problems
• Invasive alien species (IAS)

  • Every area has communities of different plants and animals linked together in food webs
  • Numbers are controlled by such factors as availability of food and the number of organisms feeding in it
  • If a plant or animal is introduced to a new environment where there is unlimited food and no natural enemies, the result is a massive increase in its numbers
• Honey bee

  • From Venezuela to fly into human living areas
• Nature reserves

  Nature reserves are areas where human activity is strictly controlled so the organisms that live there do not become endangered or threatened with extinction
• Deforestation

  Large areas of forest are being cut down every day to provide wood and farmland.

  Forest provide lots of different habitats. Once these habitats are lost, the organisms that occupied them are also lost.
• Biodiversity

  Biodiversity is a measure of the number of different kinds of organisms in an area. Trinidad and Tobago has the highest level of biodiversity in the Caribbean. Keeping a high level of biodiversity requires maintaining and protecting lots of different habitats.
• Threatened species

  Although Trinidad and Tobago boasts a high level of biodiversity, it also has a number of species of plants and animals that now exist in small numbers and are threatened with extinction if positive action is not taken.
• The greenhouse effect and global warming

  As a result of increases in atmosphere carbon dioxide and some other gases, the surface temperature of the Earth is increasing. The increase in temperature is called global warming
• Biodegradable and non-biodegradable

  Natural materials, such as vegetable waste, rot when left in the ground. They are described as biodegradable. Materials made by humans , such as glass and plastics, are often non-, biodegradable. The build- up of non-, biodegradable waste is a problem that our society must solve.
• The three R's

  People can take three steps to reduce the amount of waste that they produce:

  • Reduce - by eliminating those things that are not really necessary
  • Reuse - by using articles multiple times before they are thrown away
  • Recycle - by reusing materials to make new articles
• Human activity has an impact on the environment. As the population of the world increases, the effect humans have on the environment increases.
• Urbanisation

  The increase in the proportion of people in a country who live in towns and cities
• Urbanisation is increasing in many countries as people come to towns looking for work or for other reasons. As towns and cities grow larger, so does their impact on the environment.
• As a country develops, its industry grows larger. Industry has an impact on the environment due to increased use of land for buildings and roads, and the creation of various types of pollution.
• Genetically modified (GM) crops

  • Increase the yield
  • Reduce the time until the crop is ready to harvest
  • Make the crop resistant to attack by insects
  • Make the crop resistant to drought
• GM crops appear to be the answer to world food shortages but some scientists believe that they may cause damage to the environment in different ways.
• Invasive alien species (IAS)

  Species of organism that have been transferred from one area of the world to another, either accidentally or deliberately. Where an organism has an abundance of food and no natural enemies, its population rapidly increases at the expense of native species. IAS may also carry diseases that can be transferred to native organisms.
• Invasive alien species in Trinidad and Tobago

  • Pink mealy bug
  • Black wattle acacia tree
  • Red palm mite
  • Asian green mussel
  • Coconut moth
• Nature reserves

  • Areas where human activity is strictly controlled. This allows the organisms that are found there to live in the absence of human activities, which increases their chances of flourishing. Reserves also provide a haven where people can observe and study wildlife.
• There are a number of nature reserves in Trinidad and Tobago.
• Deforestation

  The removal of trees so that land can be used for building or for farming. The removal of trees destroys many different habitats, both in the trees and on the ground beneath them. The results of deforestation are the loss of many species of organism from an area and an increase in soil erosion.
• Biodiversity

  The number of different species of organism found in an area. Biodiversity is high when an area has many different habitats.
• Trinidad and Tobago has the highest level of biodiversity in the whole of the Caribbean.
• Urbanisation, industry and deforestation all reduce the level of biodiversity in an area. Other human activities, such as changes in land usage, also impact on biodiversity.
• Examples of threatened species in Trinidad and Tobago

  • pawi
  • ocelot
  • West Indian manatee
  • Trinidad white-fronted capuchin monkey
  • white-tailed sabrewing hummingbird
• Global warming

  A small but significant increase in the average temperature of the Earth
• Global warming

  Responsible for changes in weather patterns, melting of polar ice caps, increase in forest fires and droughts
• Greenhouse effect

  Some gases, including carbon dioxide, trap heat radiation from the Earth and prevent it from passing out into space
• Over the past 200 years the concentration of carbon dioxide in the atmosphere has slowly risen due to activities like the large-scale burning of fossil fuel
• Biodegradable

  Materials that rot in the ground
• Non-biodegradable

  Synthetic materials, such as glass and plastic, that do not rot in the ground
• Large amounts of non-biodegradable waste are a serious threat to the environment
• Reducing waste

  1. Reducing the amount of materials used

  2. Reusing things until they are worn out

  3. Recycling materials to make new things
• Improving a local environment

  1. Removing litter and waste materials

  2. Providing a litter bin

  3. Planting shrubs and plants that will attract insects, birds and other animals

  4. Providing a source of water

  5. Creating lots of different habitats