Conservation of Biodiversity (Cambridge (CIE) AS Environmental Management)

Native & Invasive Species

• Native species is the term given to species that have originated, evolved and developed in a specific ecosystem or region and are highly adapted to living in that area

• An invasive species is a species that has moved into a new ecosystem where it was previously unknown:

  • An invasive species can occur naturally as a result of a species migrating or expanding their habitat but most recorded incidents of invasive species have been caused by humans

  • In the past humans have:

    • Knowingly collected and traded species between countries via ships and aeroplanes

    • Unknowingly provided transport for invasive species to a new ecosystem (for example, rats were often living aboard explorers' ships when they landed in new locations – the rats would then leave the ship and become an invasive species)

    • Introduced alien species deliberately as biological control for pests

Problems Caused by Invasive Species

• The biological process of evolution often brings balance to an ecosystem

• Through evolution, the environment a species lives in strongly influences the adaptations that the species evolves in order to survive and reproduce successfully in that environment

• An invasive species will have evolved adaptations for survival in different environmental conditions, so when they are introduced into a new ecosystem they can upset the balance

• In a new ecosystem, invasive species will have little or none of the natural population controls that existed in their previous ecosystem:

  • For example, they will have no natural predators or competitors

• As a result they are able to increase in number at a rapid rate

• This can affect the processes within an ecosystem:

  • Competition may occur between invasive species and native species that occupy a similar niche, with the native species getting displaced, outcompeted or eventually even pushed to extinction. It could be competition for things such as prey, soil nutrients, light and space

  • Many invasive species are highly successful predators, which can potentially cause a rapid decline in their prey species (particularly if these prey species are not well adapted to this new predator)

    • For example, the introduction of the brown tree snake (Boiga irregularis) to Guam led to the rapid decline and extinction of many native bird species due to the snake's predation on bird eggs and nestlings

  • Invasive species can introduce new diseases, to which the native species have no natural immunity

  • The biodiversity of an ecosystem is negatively impacted, which reduces its overall productivity

• Humans can also feel the knock-on effects of an invasive species taking over an ecosystem:

  • The economy of a country can be impacted by the financial costs of trying to control invasive species and their negative effects

Benefits of Conserving Biodiversity

Resources of Potential Medicines

• Biodiversity is a significant source of potential medicines that are yet to be discovered:

  • Over half of all pharmaceuticals come from natural sources, with plants being a major source

  • Many medicines derived from nature are already being used to treat diseases like cancer, malaria and heart disease

• Conserving diverse ecosystems, such as tropical rainforests, ensures a wider range of potential medicines for future discovery

• For example, quinine, used to treat malaria, comes from the cinchona tree found in South America:

  • Deforestation threatens its availability, highlighting the importance of habitat preservation

Food, Wood, Fibres, Oils and Fuels

• Biodiversity is vital to our food security:

  • Diverse ecosystems with healthy populations of pollinators (e.g. bees, butterflies) ensure efficient crop pollination, leading to higher yields

  • Biodiversity also provides diverse food sources and helps maintain soil fertility

• Wood, fibres, oils and fuels:

  • Forests and other diverse ecosystems provide us with timber, cotton, palm oil, biofuels and other resources

  • Sustainable use and conservation are crucial to avoid depletion and maintain these resources for future generations

• For example, the loss of coral reefs threatens fisheries, impacting food security for millions:

  • Conservation efforts are vital to protect these ecosystems and their resources.

Diversity in Genes

• Genetic diversity within species enhances their resilience to diseases and environmental changes:

  • By conserving biodiversity, we protect this genetic diversity, ensuring species' survival and their continued ability to adapt and evolve in a rapidly changing world

• Protecting genetic diversity amongst other species can also directly benefit humans in many ways:

  • For example, diverse rice varieties with different disease resistance traits are crucial for agricultural sustainability

  • Conserving these varieties improves food security in the face of potential disease outbreaks

Ecological Services

• Healthy ecosystems offer numerous ecological services essential for life:

  • These include water purification, air filtration, flood control and soil conservation, as well as many others

• Biodiversity loss disrupts these services, ultimately impacting human health and well-being

• Combating climate change:

  • Forests and other ecosystems (e.g. seagrass beds) absorb carbon dioxide, mitigating climate change

  • Conserving these carbon sinks is crucial for tackling the global challenge of climate change

• For example, mangrove forests protect coastlines from storms and floods, while also storing large amounts of carbon:

  • Their conservation not only protects local communities but contributes to climate change mitigation too

Cultural and Recreational Value

• Biodiversity enriches our lives culturally and recreationally

• Nature provides inspiration for art, music and literature

• It also offers opportunities for outdoor recreation, improving physical and mental health

• Cultural significance:

  • Many cultures have deep connections to specific species and ecosystems

  • Conserving biodiversity helps preserve these cultural values and traditions

• For example, ecotourism relies on healthy ecosystems and diverse wildlife:

  • Conservation efforts not only protect nature but also support local economies and cultural traditions