Japan's soil-free film farming grows crops on a dialysis-derived membrane

Yuichi Mori does not grow fruit and vegetables in fields, and there is no soil in his farming at all. As the BBC reported, the Japanese scientist grows plants on a clear, permeable polymer membrane, a technology borrowed from the dialysis machines used to treat failing kidneys. The film holds water and nutrients, and the roots draw what they need from it. His invention is one example of how Japan, short of both farmland and farm workers, has been turning to technology to change the way it grows food.

"I am using materials that were used for kidney dialysis membranes," Mori told the BBC. According to the BBC, the method uses 90 percent less water than conventional farming and needs no pesticides, because the pores of the polymer keep viruses and bacteria out. His company, Mebiol, had secured patents for the invention in about 120 countries, the report said.

Highlighting Japan, a Government of Japan publication, described the system in its autumn 2015 issue. The film farming technology, called Imec, uses a film made of hydrogel, a water-absorbing polymer gel also used in disposable nappies. Its nano-sized pores, one millionth of a millimetre across, absorb water and nutrients but block germs and viruses. Because the film holds on to water, plants have to work harder to draw it out; they respond by producing more amino acids and sugar, which improves taste and nutritional value.

Mori, Mebiol's chief executive, is a polymer physics researcher. After some 20 years on catheters, artificial blood vessels and dialysis membranes at major Japanese and American chemical and medical equipment makers, he founded Mebiol in 1995; the company is based in Hiratsuka, Kanagawa Prefecture. By 2015, the same publication said, 150 farms around Japan had adopted the method, and Mebiol had applied for patents in 134 countries and obtained them in 116.

Because the film separates the crop from the ground beneath, it can be laid on desert sand, concrete or contaminated land. Highlighting Japan reported tomatoes being grown this way across Japan and in Shanghai, Singapore and Dubai. The method was also used to revive farmland on the Tohoku coast that had been contaminated with oil, sludge and salt by the tsunami after the Great East Japan Earthquake of 2011; a 1.6-hectare tomato facility in the stricken town of Rikuzentakata adopted it. South Africa's Farmer's Weekly also reported its use on farms in Dubai and China.

According to the BBC, about 85 percent of Japan is mountainous, and in roughly a decade farm producers fell from 2.2 million to 1.7 million, with an average age of 67. Citing the 2015 farm census of the Ministry of Agriculture, Forestry and Fisheries (MAFF), Nippon.com put the number of people mainly engaged in farming at 1.75 million, 63.5 percent of them aged 65 or over. Only 12 percent of Japan's land is suitable for cultivation. MAFF figures put the country's food self-sufficiency at 38 percent on a calorie basis in fiscal 2023, against a 2030 target of 45 percent.

Against that background, the BBC described Japanese fields being turned into technology centres using artificial intelligence, the internet and modern machinery. Highlighting Japan noted that film farming does not require years of learning how to work the soil, which makes it easier for young newcomers to start farming and can help with the problem of an ageing farm population with few successors.

Citing the UN World Water Development Report, the BBC said that if environmental degradation and unsustainable pressure on water continue at current rates, about 40 percent of global grain production and 45 percent of global GDP could be at risk by 2050. The executive summary of UNESCO's 2018 report noted that global water demand has been rising by about 1 percent a year and that agriculture will remain the largest user. Some 3.6 billion people live in areas that are potentially water-scarce for at least one month a year, a figure that could reach 4.8 to 5.7 billion by 2050.

Photo: AreaPhoto / Wikimedia Commons (CC BY-SA 4.0)

Sources: BBC Bangla, BBC Mundo (via La Opinión), Highlighting Japan (Government of Japan), Farmer's Weekly (South Africa), Nippon.com, FoodNavigator, UNESCO World Water Development Report 2018, Wikipedia