5.3 Human drivers

A potent driver of biodiversity, although a recent one, is humankind. That said, however, humans have had an impact on the environment throughout history – for example, as hunters and farmers. The leading naturalist and broadcaster Sir David Attenborough summarises the impact these roles have had in the following video.

Video 2 David Attenborough introduction on human impact

Transcript

This impact has recently been exacerbated indirectly via human’s increasing influence on global nutrient cycling and climate change. Moreover, activities like pollution, deforestation and over-exploitation have had a far-reaching impact on all types of ecosystems (see Figures 15–18). These human drivers can change biodiversity by influencing species composition or, at the other extreme, making some species go extinct (i.e. disappear) from a region. For example, consider the European bison, (Bison bonasus), which was hunted to extinction in Europe, or species-rich meadows that have seen a decline in their biodiversity due to over-fertilisation, which has the consequence of destabilising plant-species composition. Overall, the loss of species has accelerated drastically over the last 10,000 years, since the development of human culture and society.

Figures 15–18 Human induced biodiversity drivers. Figure 15 Deforestation of habitats for crop production (top left). Figure 16 Increased greenhouse-gas emission from intensive livestock farming (top right). Figure 17 Commercial agriculture and excessive use of pesticides (bottom left). Figure 18 Nutrient enrichment of water bodies from aquaculture (bottom right).