Planetary health research digest
Authors: Sam Hinsley
Journal: The Lancet Planetary Health (2019)

The contributions that nature makes to humans depend on local social and ecological factors, but there is a lack of high-resolution data mapping the magnitude of these contributions at a global scale. Rebecca Chaplin-Kramer, from Natural Capital Project at Stanford University, and colleagues selected water quality regulation, coastal risk reduction, and crop pollination as examples of these natural contributions to investigate. They used modelling and open-source data to produce spatially explicit global estimates of these contributions and people's needs for them, and combined these with three diverse scenarios from the Shared Socioeconomic Pathways to investigate possible future changes. The resulting estimates showed that, in many parts of the world where nature's contributions are the most beneficial to people, the ability of nature to provide them will decline, particularly in Africa and south Asia. Without sustainable development policies being enacted, billions of people will be put at risk of higher water pollution and lost crop production due to insufficient pollination. By mapping these natural contributions and people's needs for them, future locally appropriate policies can be designed to close the gaps between them. A large proportion of the species most at threat in the planet's ongoing biodiversity crisis are small arthropods. Land use has been indicated to be a key driver of arthropod biodiversity loss, but there have been few large scale studies into the specific elements responsible for this decline. Sebastian Seibold of the Terrestrial Ecology Research Group at the Technical University of Munich, and colleagues investigated changes in arthropod diversity and biomass across 150 grassland and 140 forest sites in Germany between 2008 and 2017 and how land use types affected these changes. They found declines in biomass and species diversity across grassland and forest sites, with additional reductions in abundance in grassland sites. Declines occurred at all trophic levels and in grasslands, the declines were greater in areas of increased arable land cover. These findings add to the argument that land use practices should be considered across the landscape rather than just the land being managed. Phasing out fossil fuels will be crucial to achieving the goals of the Paris Agreement, but policies to do so will need to be acceptable to the public to be effective. The phasing out of fossil fuel-powered cars presents a particular challenge given the scale of the effect this will have on people's daily lives. Adrian Rinscheid, from the Institute for Economy and the Environment of the University of St Gallen, and colleagues set out to identify what would be most publicly acceptable in policies to phase out fossil fuel-powered cars in the USA. They used a demographically representative sample of 1520 US residents who were asked to rate 24 320 hypothetical policy scenarios in a conjoint experiment to identify which characteristics made policies appealing. The policies identified as being most acceptable were those that took effect no later than 2030, used subsidies rather than taxes or bans, afforded greater (ie, >30%) reductions in pollution, and cost the least. Endorsement by trusted groups also improved acceptability, but depended on individual preferences (eg, political party affiliation). The authors make the case for early adoption of softer policy measures over more distant, but stronger options such as bans and taxes. Dietary risk factors are a major cause of non-communicable disease burden in India, including low fruit and vegetable consumption. While average fruit and vegetable consumption in India has previously been reported to be low compared with WHO-recommended levels (400 g/person/day), the key socioeconomic and demographic drivers of consumption remain unknown. Samira Choudhury, of the Centre for Development, Environment and Policy at SOAS University of London, and colleagues analysed data from a nationally representative survey of household consumption and expenditure in India for 2011–12. They found that median fruit and vegetable consumption was low at 200 g/person/day, with a highly unequal distribution. The only variables with a significant effect among the lowest percentiles of consumption were household income and belonging to socioeconomically disadvantaged castes or tribes. Although economic growth could potentially raise incomes, downstream policies that directly affect consumers, such as government provided fruit-and-vegetable-rich meals, could have more rapid effects and be more directly targeted at disadvantaged groups. Fore more on mapping nature's contributions see https://science.sciencemag.org/content/366/6462/255.fullFore more on arthropod biodiversity see https://www.nature.com/articles/s41586-019-1684-3Fore more on fossil fuel phase out see https://www.tandfonline.com/doi/abs/10.1080/14693062.2019.1677550Fore more on fruit and vegetables in India see https://www.sciencedirect.com/science/article/pii/S2211912419300884#! Fore more on mapping nature's contributions see https://science.sciencemag.org/content/366/6462/255.full Fore more on arthropod biodiversity see https://www.nature.com/articles/s41586-019-1684-3 Fore more on fossil fuel phase out see https://www.tandfonline.com/doi/abs/10.1080/14693062.2019.1677550 Fore more on fruit and vegetables in India see https://www.sciencedirect.com/science/article/pii/S2211912419300884#!