Three principal changes are needed for a more biodiversity-supporting food system. Humanity must shift towards more plant-based diets, set aside more land as protected natural habitat, and adopt more sustainable farming methods.
Our food system today is driving both environmental harm and deteriorations in public health. Its current design is also amplifying external risks to society, as COVID-19 has demonstrated. The pandemic has highlighted the high degree of risk concentrated in certain food supply chains, poor labour standards in food-processing plants that have accelerated the spread of the disease among workers, and the limitations of ‘just-in-time’ business models that have depleted emergency food stores.
Moving to a food system that supports environmental and human health requires fundamentally changing consumption habits and redesigning how food production systems utilize natural resources. Reducing the conflict between humanity’s requirement for food and the negative impacts of food production on biodiversity and the environment will not be achieved simply by identifying a single approach to biodiversity-friendly farming. At the same time, building the resilience of the food system to respond to ‘black swan’ events such as COVID-19 cannot be done through ‘tweaks’ at the margins alone. Instead, transformative change, including a realignment of the incentives that drive unsustainable practices, is required both to the way we produce food and to what we consume.
The successful redesign of the food system in support of biodiversity and improved public health will depend on three key ‘levers’: changing our diets; setting aside land for biodiversity; and adapting how we farm.
3.1 Dietary change
The first key lever for food system redesign is to change diets in such a way as to reduce overall demand for food, and thus reduce demand for the use of land that supports its production. Evidence of the potential for dietary change to deliver fundamental shifts in agriculture and land use has been mounting in recent years. Scientists, civil society and policymakers are increasingly recognizing dietary change as a central pillar in food system transformation. A number of high-profile reports have begun to outline pathways through which all actors in the food system – from financers to producers to retailers to consumers – can effect positive behaviour changes in favour of healthier diets from sustainable production systems.
The importance of dietary change to redesign of the food system stems from three key principles. Firstly, on average and at a global level, we produce more food than we need per capita. Globally, as much as a third of the edible parts of food produced for human consumption are lost or wasted, equal to around 1.3 billion tons per year, either on the farm, in transit, through processing, or at the point of retail and consumption. Secondly, the environmental footprint of food – its associated land use, GHG emissions, water use and biodiversity impact – varies significantly from one product to the next. In general, the largest differences occur between animal-sourced and plant-sourced foods, with the latter having smaller footprints; in some cases, substantially smaller (see Figure 7). And thirdly, demand for the most environmentally damaging foods is both high and rising, a trend partly associated with nutrition transitions that are increasing demand for animal products.
Were global dietary patterns to shift to the extent that we did not waste food, overconsume calories or demand excessive amounts of the most environmentally damaging foods, this would very significantly reduce total demand for food – and hence total demand for land and other natural resources. For example, a switch from beef to beans in the diets of the entire US population could free up 692,918 km2 – equivalent to 42 per cent of US cropland – for other uses such as ecosystem restoration or more nature-friendly farming. Such a shift would also contribute substantially to climate goals (in this example, meeting between 42 and 74 per cent of the US GHG reduction goal for 2020). It would likely contribute to a range of other public goods including improved dietary quality and reduced incidence of diet-related disease associated with overconsumption of red and processed meat. Pandemic risk could also be significantly lowered by reducing animal farming. While the convergence of global food consumption around predominantly plant-based diets is the most crucial element in addressing demand, additional measures (such as efforts to reduce waste and overconsumption of calories) are required to bring food system emissions in line with the temperature goals of the Paris Agreement on climate change.
3.2 Setting aside land for biodiversity
The second key lever for creating a more biodiversity-supporting food system is to set aside land specifically for the conservation and proliferation of habitats and wildlife. Biodiversity is highest in areas of unconverted land. Even farming practices that are designed to be wildlife-friendly require some degree of modification of natural habitat. From a purely theoretical perspective, and according to a growing body of academic literature, setting aside land for biodiversity to the exclusion of other uses, including farming, and either protecting or restoring natural habitat would offer the most benefit to biodiversity across a given landscape.
Setting aside land for biodiversity to the exclusion of other uses, including farming, and either protecting or restoring natural habitat would offer the most benefit to biodiversity across a given landscape.
The value of preserving undisturbed habitats and ecosystems – both for the sake of biodiversity and to support natural carbon sequestration and storage – has underpinned many of the global efforts to preserve primary forest cover, particularly in the tropics. When it comes to restoring native ecosystems, the carbon sequestration potential of particular measures varies according to geographical location and the type of underlying native ecosystem being restored. For example, returning all permanent pasture worldwide to its native forest cover would store 72 gigatonnes of carbon (GtC), whereas returning pasture to its native grassland cover would store less than half this amount (34 GtC), even though native grassland covers three times more land area than native forest. The biggest potential for carbon sequestration through such ecosystem restoration efforts is concentrated in high-income and upper-middle-income countries, which account for 70 per cent of the carbon that would be sequestered by restoring land currently occupied by animal agriculture.
The greatest gains for biodiversity will occur when we preserve or restore whole ecosystems. With some exceptions, this will typically require significant areas of land to be left or managed for nature, primarily because the extinction risk for any species grows as its population size shrinks, and because many large animals require a large area of habitat to sustain an adequate population. Human dietary shifts are thus essential in order to preserve existing native ecosystems and restore those that have been removed or degraded.
3.3 Adapting the way we farm the land
The third lever for transforming the food system in support of biodiversity is to adopt more biodiversity-supporting modes of food production. One way to do this is to retain pockets of habitat for wildlife within the agricultural landscape (some of which can be on farms; others can be patches of land ‘spared for nature’ within the wider farming landscape). The other way is to change farming methods.
There are three key avenues through which the latter can be achieved. Firstly, we can decrease the volume of inputs. Reduced-input farming has already been widely adopted in developed countries through precision agriculture. Precision agriculture involves the use of a range of technologies to target more efficient use of inputs (according to the ‘4 Rs’ principle: the right source, in the right amount, in the right place, at the right time).
Secondly, we can substitute certain inputs or practices for more sustainable alternatives: forgoing chemical and synthetic inputs as much as possible and instead using ecological processes to manage soil fertility (through crop rotations, for example), supporting natural pollination and pest control, and moving to methods such as ‘no-till’ farming that limit disturbance of natural processes and habitats. And thirdly, we can switch to modes of production that utilize land and other natural resources in fundamentally different ways, for example replacing conventional agriculture with agroforestry, or converting to agro-ecological approaches (see technical annex for further discussion). Since such practices imply breaking out of many of the ‘lock-ins’ associated with today’s system – including land tenure models, the sunk costs of large farm machinery, and the nature of the dominant supply chains – adoption remains limited to date.
Dietary change is a necessary global enabler to allow widespread adoption of nature-friendly farming without increasing the pressure to convert natural land.
There are many specific ways in which agriculture can become more nature-friendly and support biodiversity (including through agro-ecological farming and regenerative farming, of which organic farming is an example). As outlined above, alternative approaches typically require the use of natural processes to support production, rather than a full substitution of synthetic inputs (nitrogen, pesticides) with natural ones to enable specialization at scale. These approaches are typically associated with enhancing diversity: of farm outputs (genetics, agroforestry), land use across space (to improve biodiversity for ecosystem services) and time (e.g. crop rotations). While some approaches may increase agricultural productivity, in general nature-friendly farming is less productive than conventional methods. For example, on a like-for-like comparison, organic farms typically yield 34 per cent less than intensively managed farms. Even if farm-level incomes can be maintained via appealing to premium markets, dietary change is still a necessary global enabler to allow widespread adoption of nature-friendly farming without increasing the pressure to convert natural land.
In essence, these three avenues – gaining efficiency, substituting artificial processes with ecological ones, and redesigning the system – are about maintaining adequate food yields while reducing environmentally damaging inputs. In other words, they are about sustainably intensifying production. While the concept of ‘sustainable intensification’ is subject to much debate and is often used to describe practices that are far from sustainable, the underlying principle is one that now lies behind approaches such as ‘ecological intensification’ (see Box 3).