Thread by @ZoologyDave

Who wants a nice thread on environmental pressures from the global food system? You know you do @GlobalFoodLeeds @SRILeeds 1/

An awesome team led by @BSHalpern & @ucsb_nceas calculated and, for the first time, produced a spatial map of where pressures from the food system are produced. Paper at: nature.com/articles/s4189…, email me if you want a PDF 2/

We found that these pressures (disturbance, nutrient pollution, water use, and GHG emissions) are wildly uneven in their distribution. Over 90% of pressures come from just 10% of the world; with 40% of pressures from the just 1% 3/

Perhaps unsurprisingly (given this uneven spread), the distribution of individual pressures are quite similar: e.g. high water use is associated with high nutrient pollution. 4/

...although there are some differences: places where only one or two pressures overlap 5/

Perhaps less surprising is the finding that a few countries dominate cumulative pressures: India, China, US, Brazil and Pakistan have nearly 50% of pressures (with a big chunk of the world's food production and population) 6/

And, as you may have guessed, livestock represent an enormous proportion of the world's environmental pressure from food systems (for not a huge amount of food produced) 7/

Livestock also provide a really interesting insight into the linkages between marine and terrestrial #foodsystems. A lot of marine food is used to supply livestock, and a chunk of crops feed #aquaculture farms. What you do on land matters in the sea, and vice-versa 8/

So what does this mean for #sustainability? Well, firstly, we looked at PRESSURES not IMPACTS. The latter will require an in-depth understanding of the sensitivity of different environments: a litre of water in Leeds does not equal a litre in California 9/

See this ace diagram from @cdkuempel doi.org/10.1016/j.onee… 10/

So we provide the basis for other people to understand the pressures on their particular system, and investigate what this means for the #biodiversity, the #environment, and for people there. 10/

There are some big findings here, but I think the real value is what this research allows us to do now. Understanding #foodsystems #sustainability requires putting all food, & all pressures, on the same table doi.org/10.1073/pnas.1…. Only then can you understand what to do 11/11