Climate challenges make sustainable agriculture an urgent priority

Around the world, alarm bells are ringing over food security issues. On December 12, Finland announced plans to increase its emergency grain stocks in preparation for possible shortages; a catastrophic crop failure in the summer of 2021 left the country’s grain levels at a 10-year low.

A report released the same week warned that approximately 8.3 million people across Somalia are likely to face crisis levels of food insecurity next spring, following five consecutive seasons of poor rainfall. The UK’s National Farmers Union warned that the country is sleepwalking into a food supply crisis, with yields of energy-intensive crops such as tomatoes, cucumbers and pears likely to hit all-time lows since records began in 1985.

The war in Ukraine and its myriad consequences have certainly played a role in sparking these food emergencies . “It’s not whether we are going to have a food crisis,” Svein Tore Holsether, the head of Norwegian fertiliser producer Yara International, cautioned back in March, just a few weeks after the invasion of Ukraine. “It’s how large that crisis will be”.

Even before the conflict in Ukraine, however, climate change was putting increasing strain on food production around the world. Yields of staple crops like maize are expected to experience significant and imminent declines: one NASA study estimated that the knock-on effects of greenhouse gas emissions — including rising temperatures and changing rainfall patterns — may shave some 24% off global maize production by 2030, a steep decline which the study’s lead author acknowledged would have “severe implications worldwide”.

Countless other critical crops are likely to be similarly affected–studies suggest that world crop yields are expected to decrease by 25% overall over the next 25 years due to climate change — at the same time that global food production needs to double in order to compensate for the estimated growth in the human population, estimated to have reached the milestone of 8 billion last month.

Under the circumstances, developing more sustainable agricultural methods allowing farmers to adapt to the transforming climate is more essential than ever.

Innovating to overcome soil salinity

One major challenge is a profound decrease in the amount of arable land available to be cultivated. Factors including erosion and pollution have stripped the Earth of more than a third of its arable land since 1975, and some 43% of the global population lives in areas affected by land degradation.

Soils are not only steadily losing carbon, but a combination of heat stress and rising ocean temperatures are leading to an important increase in soil salinity, driving crop yields down and squeezing farmers’ margins to the point where cultivation is no longer financially viable on some plots of land.

One study estimated that the effects on global food production are substantial — each year, roughly 124 trillion kilocalories are lost to soil salinity, enough to feed some 170 million people every day.

Fortunately, some entrepreneurs and researchers have found promising solutions to reclaim land which ordinarily would have been unsuitable for agricultural activities due to high salt content. Italian entrepreneur Gaetano Buglisi has developed a number of projects aiming to revitalise abandoned or inadequately used agricultural land, and today cultivates more than 1,000 hectares of fruit in the south of Italy.

While this land’s salinity made it unsuitable for most crops and conventional farming techniques, Buglisi managed to find particular varieties of exotic fruit, such as mangoes, that were able to withstand the land’s high salt content, and coupled them with Agriculture 4.0 techniques to regenerate both the previously-abandoned land and the agricultural community surrounding it.

Given the sharply accelerating effects of climate change on Italian agriculture — the country suffered large-scale crop losses in the summer of 2022 following the worst drought in 70 years, with widespread salt contamination — projects like Buglisi’s must become more common.

In a similar vein, researchers from the King Abdullah University of Science and Technology (KAUST) in Saudi Arabia — a country which has particularly salty soil that has made sustained agriculture difficult and is especially vulnerable to climate change — have established a “Salt Lab” to find crops that are naturally hardier in salty soil, like the mango varietal which Gaetano Buglisi identified.

The Salt Lab has already had a number of important breakthroughs; its researchers discovered a genetic mutation in some strains of barley with 30% higher yields in high-salinity soil than other strains and are now partnering with agtech startup Red Sea Farms to operate a pilot greenhouse testing whether tomatoes can successfully be grown using mostly saltwater to irrigate the crops, as well as to cool the greenhouse in an energy-efficient manner.

Developing ways to preserve increasingly scarce water resources

If the pilot greenhouse is a success, it could provide a blueprint for countless regions which are currently inhospitable to agriculture due to insufficient freshwater.

While naturally arid countries like Saudi Arabia have always struggled with a dearth of freshwater, water resources are now becoming scarce around the world: the amount of water available to each person on average has declined by more than 20% over the past two decades. Worryingly, this scarcity comes just as climate-induced extreme heat and droughts spark a need for greater crop irrigation.

In addition to the possibility of saltwater irrigation that Red Sea Farms and KAUST are trialling, there are a number of encouraging projects aiming to keep crop yields high while using less of our precious freshwater resources.

Dutch businessman Pieter Hoff, a former lily planter, invented the Waterboxx “plant cocoon,” a device constructed from recycled cardboard which collects overnight condensation to water plants in small doses, while also preventing water from evaporating and protecting plant roots from the sun.

Over the past five years, more than 55,000 trees have been planted using 20,000 Waterboxx units — the device is reusable — using up to 90% less water than with drip irrigation.

Other innovators are targeting drip irrigation itself for improvement. Uri Shani, the former chairman of Israel’s water authority and a professor of soil physics at the Hebrew University of Jerusalem, founded irrigation startup N-Drip. Shani conceived a new design of emitter — a small but critical component of drip irrigation systems — capable of functioning with only the water pressure provided by gravity.

The first field trial of N-Drip, in Eswatini, indicated that the system managed to increase crop yields by 30% while using less water, and the system is now undergoing larger trials in 17 countries, from the southwestern US to Vietnam.

The food crises around the world are indeed alarming, particularly since the recent COP27 climate conference showcasing a lack of ambition for the decisive action that is needed to slow the alarming pace of climate change. in the coming years, agriculture will be under increasing strain as extreme weather events proliferate, soils become saltier and drier, and freshwater resources more scarce.

As such, crafting a more resilient agricultural system — whether by revitalising underutilised land with carefully-chosen crop varieties or reinventing irrigation systems to drastically curb freshwater use — should be a matter of urgent priority.