Over the past half-century, the need to feed a growing world population has led to markedly expanded and intensified agricultural production. This transformation has led to the degradation of the global environment. The loss of biodiversity can disrupt key ecosystem services to agriculture, such as crop pollination and biological pest control, which underpin the final provisioning service of crop production. Around 20% of the world’s agricultural areas yield less than they did 20 years ago.
A study compiled an extensive database comprising 89 studies that measured richness and abundance of pollinators, pest natural enemies, and associated ecosystem services at 1,475 sampling locations around the world. The researchers partitioned the relative importance of richness, total abundance, and evenness in driving biodiversity–ecosystem services relationships. They found clear evidence that the richness of service-providing organisms positively influenced ecosystem service delivery. This was detected for both pollination and pest control in almost all the studies.
Furthermore, landscape simplification indirectly affected ecosystem services by reducing both the richness and abundance of service-providing organisms. Roughly a third of the negative effects of landscape simplification on pollination was due to a loss in pollinator richness. This effect was even greater for pest control where natural enemy richness mediated about 50% of the total effect of landscape simplification. In turn, there was decreased crop production. Insecticide use undermined the full potential of natural pest control.
In sum, the study found strong evidence for positive biodiversity–ecosystem service relationships, highlighting that managing landscapes to enhance the richness of service-providing organisms is a promising pathway toward a more sustainable food production globally. Preserving biodiversity-driven services will consistently confer greater resilience to agroecosystems, such that we could expect improved crop production under a broader range of potential future conditions.
https://www.rural21.com/english/news/detail/article/loss-of-biodiversity-causes-yield-reductions-00003446/
– Third World Network
