PLANET EARTH'S 'doomsday vault' of seedstock of food crops now contains one million varieties, following the addition of a further batch of specimens.

The Svalbard Global Seed Vault, built in 2008 into a mountainside on the island of Spitsbergen in the Norwegian Arctic archipelago of Svalbard, halfway between Norway and the North Pole, was designed as a storage facility to protect vital crop seeds against the worst cataclysms of nuclear war or disease, and thus safeguard global food supplies.

It is only opened a few times a year in order to maintain the best atmosphere to preserve the seeds inside, and was most recently accessed to deposit newly collected seeds from India, Mali, Peru and the Cherokee Nation in the United States, which banked samples of maize, beans and squash. At the same time, the Royal Botanical Gardens at Kew banked seeds harvested from the meadows of Prince Charles’ private residence, Highgrove, including from grass species, clovers and broad-leaved flowering herbs.

The Svalbard vault also serves as a backup for plant breeders to develop new varieties of crops. The world once cultivated around 7000 different plants, but mankind now gets about 60% of its calories from only three main crops — maize, wheat and rice — making food supplies vulnerable if climate change causes those harvests to fail.

“The seed vault is the backup in the global system of conservation to secure food security on Earth,” said Stefan Schmitz, executive director of the Crop Trust, the Bonn-based organization which manages the vault.

“We need to preserve this biodiversity, this crop diversity, to provide healthy diets and nutritious foods, and for providing farmers, especially smallholders, with sustainable livelihoods so that they can adapt to new conditions.”

In October, Norway completed a year-long upgrade of the vault, which was built at Svalbard because it offered such a cool and stable location, but which has itself suffered effects driven by climate change, with an unexpected thaw of permafrost letting water into its tunnel entrance – although no seeds were damaged.