Skip to 0 minutes and 6 secondsThe need to produce food has had the most profound impact on the natural resource base of our planet. It's the largest user of land over all other human activity. Something like 38% of the planet's ice free surface is used for the production of food one way or another. It's also the major user of water, so 70% of irrigation water is used for agriculture. And it also uses finite resources such as fossil fuels, as well as minerals, such as phosphorus.
Skip to 0 minutes and 51 secondsAnd another what you could call a natural resource, which is biodiversity, which has a value, not just in its own right, and that is of course hugely important, but also because it's the repository for human future needs, whether it be medicines or further species that could be used for food production, and so forth. Land and soil is fundamental. Soil is very susceptible to erosion and degradation. Both chemical loss, the reduction in soil organic matter, or the physical loss of soil through erosion itself. The important point about soils is that they take a very long time to renew, they are renewable in that they can be recreated, but once gone it's very challenging to return the area to its original state.
Skip to 1 minute and 52 secondsBiodiversity and ecosystem services, terribly important as well. Multiple functions to do with primary production through the provision of water, pollinator species as we've seen, and the sustainable use of biodiversity has to be seen in the whole, in the round, so that we look at the whole ecosystem, not just one or two important species. The interactions in the ecosystem are paramount to maintaining the ecosystem service. The nutrient losses to the environment-- pollution-- are also an area of concern, which can actually come back and affect the primary production itself, either through its quantity or its quality. An example would be eutrophication in coastal zones leading to, for instance, red algal bloom which produces a toxin in fish and shellfish and the like.
Skip to 2 minutes and 50 secondsSo how we produce food, and what we produce, and what we produce it on and with, has profound consequences for the future of the planet and the future of humanity. Particularly when we take into account that we're already producing food in ways that are very, very damaging for these natural resources. We're polluting waterways we're extracting water at unsustainable rates, we're pumping greenhouse gases into the atmosphere, and that climatic stability is another natural resource as it were. And of course we're continuing to clear land and degrade land, and land is the ultimate finite resource. We only have one planet. But all the signs are that the pressures on this natural resource base are set to grow as the population grows.
Skip to 3 minutes and 51 secondsSo we are now over seven billion people on the planet, by 2050 we could be nine, we could be ten billion people. And it's not just a question of more mouths to feed, but it's a question of each of those individuals wanting to consume foods that a more resource intensive. So particularly I'm thinking of animal products, meat and dairy products, which require not just more land but also more water, and are associated with all the postharvest stages such as refrigeration, particularly important with perishable foods, such as meat and dairy products, and that have a disproportionately high climate impact-- they're major emitters of greenhouse gases.
Skip to 4 minutes and 43 secondsSo we think of the food chain which is one element of the food system, the production, distribution, processing, and cooking and consumption of food. And of all those stages, in general the agricultural stage is the major user of resources, and the major contributor to environmental impacts. So in a developed country such as the UK about half of all greenhouse gas emissions arise from the agricultural production stage, they also overwhelmingly use more land than any other stage, and the same applies for water use. At a global level agriculture becomes even more dominant, because in many parts world the postharvest supply chains are somewhat less industrialised and less elaborate.
Skip to 5 minutes and 43 secondsBut that general weight of concern resting on agriculture does somewhat depend-- depending on the food type that we're talking about. So with a livestock product-- meat or dairy products-- the bulk of the environmental impact occurs at the agricultural production stage-- the rearing of those animals. But if you take products such as a horticultural product, which is produced for export markets, and because of its high perishability is often transported by air, the major environmental impact occurs at the transport stage.
Skip to 6 minutes and 23 secondsAnd if you take products such as tea or coffee or cocoa, which, they use land, they require irrigation water and so forth, but actually then you get into the processing, the distribution, and the consumption-- you boiling the kettle to make yourself a cup of tea or a cup of coffee-- that can carry quite a lot of the environmental weight of the product.
Earth's natural resources
We heard earlier this week that natural resources underpin key food system activities. Now that we have explored food system actors and activities in more detail, here Dr. Tara Garnett and Dr. John Ingram from the Environmental Change Institute, University of Oxford, discuss the natural resources that are most crucial to food systems, particularly to agricultural production.
Later in the course we will consider how the pressure on Earth’s natural resources may change in the future, but in this video we get a glimpse of the food challenges we may face if we don’t move towards more resource-efficient and environmentally-sustainable food systems very soon.
Image Sources: “Terraced rice paddies near a Red Zao vil” (CC BY-NC-ND 2.0) by World Bank Photo Collection and “Rice paddies and recently cleared forest land in the Thanon Thong Chai Range, Chiang Mai Province” (CC BY 3.0) by Takeaway
© Stockholm Environment Institute