For most of us in Europe, 8th August is just another summer's day. But it also marks a more chilling moment in our calendar: the day our world starts going into debt. By the 8th we will have used up the supply of natural resources that the Earth can regenerate within one year. For the remaining 40 percent of the year, we will add to the overdraft of nature's budget.
Called 'Earth Overshoot Day', it is a stark reminder that the planet we live on has natural limits within which we must live. And perhaps no other sector is feeling these boundaries more than the agriculture sector that feeds us. As the population surges and our diets become more resource-intensive (think meat, dairy, oils), agriculture is faced with the Herculean task of meeting an ever-increasing demand for food while helping to sustain our landscapes and the very biosphere of the Earth itself.
Today, agriculture is the world's single largest driver of global environmental change, much of it negative. So the basic challenge is this: can we produce even more food by intensifying our agricultural production, yet stay within the Earth's budget? Can agriculture become a key contributor to a global transition to a sustainable world? According to a recent paper published in scientific journal Ambio, the answer is yes, if we take better care not to cross the 'planetary boundaries' that affect our food system most directly. This is what we need to do.
We need to make our soils a carbon trap. We must transform agriculture from the world's single largest source of greenhouse gases into a major sink by adapting the way we farm so we capture carbon in the soil. According to the Intergovernmental Panel on Climate Change, about 90 percent of agriculture's technical potential to reduce the effects of climate change lies in this very method.
We have to grow more food on less land and reduce waste. We need more forest cover for our Earth system to function sustainably rather than less. To reverse the trend of deforestation, we have to drastically reduce the conversion of forests into agricultural land by making existing farmland more productive and reduce the estimated 30% of waste in the food supply chain. Part of the answer lies in increasing the uptake of crop and livestock varieties that have a high ratio of productivity to use of inputs.
We must get more crop per drop. Around 70% of global freshwater is used for agriculture. To get back on budget, we need to improve water productivity in agriculture by 50 percent by 2030 by using water more productively. This can be done through conservation agriculture and managing water at the watershed level. Such measures can also improve resilience to climate shocks.
We should protect our biodiversity. Agricultural expansion is undermining the Earth's biodiversity at an alarming rate. Healthy agriculture depends on this genetic diversity, so we must encourage farming systems that adopt an ecosystems approach, that reduce biodiversity loss in agricultural landscapes and value the services that the natural environment provides, such as the flood regulating effect of wetlands.
We need to use fertilizer more efficiently and recover nutrients. We are extracting too much nitrogen from the atmosphere and we are running out of the phosphorus we need to fertilize our food crops. The excess runoff pollutes our river and groundwater systems. We have to rebalance the way we use fertilizer, without increasing overall use and encourage the recycling of nutrients from human, agricultural, livestock and solid waste.
We need to reduce the energy footprint of agriculture. Groundwater irrigation supports an increasingly large proportion of food production with implications for energy use and resource depletion. We have increasing opportunities to expand the use of solar power and more efficient irrigation and food processing practices and thereby reduce emissions.
To tackle these challenges, we need to enlist the help of the world's farmers. Over 2.5 billion smallholders provide up to 80 percent of the food in Asia and sub-Saharan Africa. For them to produce more over the long term, and reduce their ecological footprint, they have to be encouraged to shift their main focus beyond productivity to sustainability. To do this we will have to invest heavily in research into the crops, diets and farming practices that are healthy both for people and the planet.
We already have ways to achieve some of this painlessly - the so-called 'win-win' solutions. For example, farmers practicing conservation agriculture in Brazil (which involves minimal soil disturbance to maintain moisture, nutrients and carbon content) lost 30 percent less of their maize crop than conventional farmers when drought hit. Encouraging a shift to less resource-intensive diets - lower in refined sugars and fats - will address the twin challenge of improving global health and reducing emissions of greenhouse gases and resource footprints.
In India, solar powered irrigation pumps offer an attractive way to access more groundwater to produce more food. This has the advantage of reducing emissions whilst improving productivity. But there are huge concerns about the sustainability of already diminished groundwater resources. To solve this, the International Water Management Institute and partners are testing ways to incentivize farmers to put unused electricity back into the national grid. This represents a triple win for farmers, the environment and the government.
We cannot pretend this will be easy - staying within our natural resource budget will require difficult trade-offs. But it is in all of our interests, as food producers or consumers, to tread more lightly on our planet which is already buckling under the pressure of our demands. Earth Overshoot Day should serve as a wake up call. Collectively, we need to balance nature's books, and live within our planet's boundaries.