In 1798, English cleric and scholar Thomas Robert Malthus published a study concluding that the world’s population would grow faster than the supply of food.

Basing his conclusion on the Law of Diminishing Returns, Malthus theorized that populations were growing in geometric or exponential progression while food production was increasing in arithmetic progression. The result could only be catastrophic famine.

Over the centuries, the Malthusian Theory failed to pan out. While pockets of famine have existed off and on in some regions of Africa and Asia, the world as a whole hasn’t outgrown its ability to feed itself.

What Mathus failed to foresee were technological innovations such as the steel plow, the tractor, the threshing machine, disease-resistant grains and chemical fertilizers — developments that led to dramatic increases in food production.

Fast-forward to 2018 and we are hearing murmurs from a number of economists and agronomists warning of a potential shortfall in the world food supply — the Malthusian-connected cause behind it being rampant population growth.

Demographers project that the current world population of 7.6 billion will grow to about 10 billion in just a few decades. The UN’s Food and Agricultural Organization estimates that an increase of at least 50 percent in food production levels from 2010 will be needed to provide for the world’s food security.

There are a number of serious obstacles to achieving that kind of increase. We are not gaining any natural resources. In fact, elements such as land and water are diminishing throughout much of the world.

If predictions are true that 7 out of 10 people will live in a city by 2050, we are not gaining any farmers either. To put this into perspective, less than 2 percent of the U.S. population is currently employed in agriculture. It was close to half the population in 1900.

The world also is running out of farmland at an alarming rate. Nearly a million acres of it across the globe have disappeared due to urban development, erosion and overuse during the last century alone.

The American Farmland Trust estimates that farmland in the U.S. is disappearing at a rate of two acres per minute. Pointing to the serious effects of erosion, a study from the University of Sheffield’s Grantham Centre for Sustainable Futures reports that roughly a third of the earth’s arable land has eroded just during the last 40 years.

Toss in the unpredictable impact of climate change and the problems facing the agricultural industry loom even more daunting. Drought and erratic weather patterns are causing farmers worldwide to scramble with issues of crop management and protection.

There are problems too even after food is produced, owing to waste and inefficiencies. Up to 30 percent of food is wasted on the farm, between farm and store — and in the home.

To some extent, new developments in agriculture such as factory farms and tech-driven innovations, including improved irrigation methods, precision ag equipment, farm management software and genetically modified seeds have improved farming efficiency – but it is clear that even greater technological advances are going to be required to avoid a future food crisis.

Fortunately, there are some exciting innovations under development and on the horizon that could go a long way toward providing the food we’ll need to feed the world.

Here’s a look at some of them:

Underwater Farming

Instead of growing food on the land’s surface, why not utilize the vast area beneath the sea? This is precisely what two different projects are looking to do.

One is Nemo’s Garden, a project underway in Italy that uses transparent underwater bubbles (biospheres) that house and grow edible plants, including beans, strawberries, lettuce, garlic and basil. Plants are kept hydrated by drips of water condensing on the inner walls of the biospheres — and the near constant temperature between day and night creates ideal growing conditions.

American entrepreneur Bren Smith has a different idea. He calls it a 3-D Ocean Farm, and it is basically a vertical underwater garden. Kelp (seaweed) and mussels grow on ropes floating above oyster and clam cages located at the bottom of Long Island Sound.

Anchored to buoys, this simple setup is capable of truly impressive yields. The farm already has the capacity to grow 20 tons of sea vegetables and 500,000 shellfish per acre every year.

The Vereos Floating Greenhouse

A floating hydroponics farm developed in Germany offers another intriguing solution to feeding coastal communities. The solar-powered, 42-square-foot plastic-domed Vereos makes and recycles fresh water using a small onboard reverse osmosis plant and is fitted inside with shelving for growing vegetables.

Rooftop Greenhouse Gardens

City dwellers know finding green space can be a problem — and a group in Santa Cruz, California, called Cityblooms is answering the challenge with a connected series of lightweight hydroponic rooftop microfarm modules that will grow just about anything except root vegetables.

The GrowUp Box

London-based urban farming firm GrowUp has devised a method that allows customers to grow plants and raise fish in their own backyards with the GrowUp Box.

The box is made from a recycled shipping container and has two levels. On the top, greens are grown in vertical columns, while tilapia are farmed in tanks at the bottom.

It is largely self-sustaining with only minimal input required. The plants work to purify the water while fish waste fertilizes the plants above. The company is now developing a commercial-scale version of its aquaponics farm.

Local Roots Container Farm

Los Angeles startup Local Roots retrofits 40-foot-long shipping containers, turning them into "TerraFarms" that yield as many leafy greens as five acres of farmland — but 20 days faster and using as little as 1 percent of the water.

Climate controls and LED grow lights help nurture crops that so far include butterhead lettuce, kale, basil and arugula. The company leases TerraFarms to wholesalers, restaurant chains and SpaceX. The United Nations is conducting field tests on them as well.

Agrihoods

Here’s a concept for producing more food that’s not so much high-tech as it is simple and sensible.

Community-based cooperative farming is hardly a new idea either — it has been practiced in the U.S. since the early 18th century. But in the context of today’s realities, including the widespread development of master-planned communities, farming in the hood is reemerging as a trend in residential living.

According to the Urban Land Institute (ULI), more than 200 residential developments across the country — including such biggies as Rancho Mission Viejo in California and Atlanta’s Serenbe — have embraced the agrihood concept by setting aside plots of land for growing produce.

Volunteers cultivate the crops and either share the bounty and/or sell it to fellow residents. Not only do residents get a feel-good taste of country life, but also as ULI spokesman Ed McMahon points out, "Farms are less expensive to build than fairways."