3.2 Human impact on biodiversity

Guiding question

What causes biodiversity loss, and how are ecological and societal systems impacted?

Here’s part 1 of a 2-part video series explaining the big ideas in the slide deck at the top of the page.

This is the second part of the series for the SL content in ESS topic 3.2.

Click here for a Quizlet flashcard et about topic 3.2 Human impacts on biodiversity.

SL and HL knowledge statements

3.2.1. Biological diversity is being adversely affected by both direct and indirect influences.

3.2.2 Most ecosystems are subject to multiple human impacts.

This video nicely explains how combinations of human activities negatively influence biodiversity and ecosystem resilience. I suggest listing the impacts mentioned in the video, then creating a feedback diagram to show how they reinforce one another.

3.2.3 Invasive alien species can reduce local biodiversity by competing for limited resources, predation and introduction of diseases or parasites.

This TED-Ed video succinctly explains several examples of invasive species that are relevant to our ESS syllabus.

This short video demosntrates how invasive species may have both positive and negative impacts on ecosystems.

3.2.4 The global conservation status of species is assessed by the International Union for Conservation of Nature (IUCN) and is published as the IUCN Red List. Status is based on number of individuals, rate of increase or decrease of the population, breeding potential, geographic range and known threats.

3.2.5 Assigning a global conservation status publicizes the vulnerability of species and allows governments, non-governmental agencies and individual citizens to select appropriate conservation priorities and management strategies.

Here’s a video that explains the IUCN Red List and the factors it uses to classify organisms by vulnerability to extinction.

3.2.6 Investigate three different named species: a species that has become extinct due to human activity; a species that is critically endangered; and a species whose conservation status has been improved by intervention.

The dodo is one of the most famous examples of a species that was driven to extinction by humans.

The kakapo is a flightless parrot native to New Zealand. It is critically endangered, with only around 200 individuals remaining in the wild.

The California condor is a good example of a species that has (at least partially) recovered from its threatened status.

It’s not all doom and gloom – here are some examples of species whose Red List status has improved thanks to conservation efforts. These are also good examples of flagship species: charismatic organisms that draw attention to build awareness.

3.2.7 The tragedy of the commons describes possible outcomes of the shared unrestricted use of a resource, with implications for sustainability and the impacts on biodiversity.

3.2.8 Biodiversity hotspots are under threat from habitat destruction, which could lead to a significant loss of biological diversity, especially in tropical biomes.

3.2.9 Key areas that should be prioritised for biodiversity conservation have been identified on the basis of the international importance of their species and habitats.

3.2.10 In KBAs, there is conflict between exploitation, sustainable development and conservation.

3.2.11 Traditional indigenous approaches to land management can be seen as more sustainable but are facing challenges of population growth, economic development, climate change and a lack of governmental support and protection.

3.2.12 Environmental justice must be considered when undertaking conservation efforts to address biodiversity loss.

3.2.13 The planetary boundary “loss of biosphere integrity” indicates that species extinctions have already crossed a critical threshold.

Practical activities

Practical 3.2.2 – Investigate human impacts on biodiversity

Possible engagement opportunities

Add these from the syllabus and expand on them for local context. Explicitly link to UN SDGs.
Assess the tensions between exploitation, sustainable development and conservation in a local ecosystem or protected area.
Raise awareness of indigenous land rights.
Raise awareness of endangered species and volunteer in a local NGO for wildlife rehabilitation.

Happy learning!