South Korean environmentalists participates in a rally held to commemorate the Fukushima nuclear disaster on the eve of the one year anniversary of Japan's earthquake and tsunami on March 10, 2012 in Seoul, South Korea. Currently four nuclear power plants are in operation in South Korea while the government plans to increase the number of reactors to 32 by the year 2021. (Photo by Chung Sung-Jun/Getty Images)

A Dartmoor Hill pony foal runs on the moor on Dartmoor on May 17, 2011 in Princetown England. Although a tourist attraction, especially during the foaling season and often seen as part of the landscape of Dartmoor, many ponies face an uncertain future due to unsustainable breeding and their falling market values. The charity South West Equine Protection estimates that last year 1500 ponies were slaughtered – with many being sold for lion meat to nearby zoos. Along with other equine charities, they are calling for the removal of stallions from the moor to bring numbers down to sustainable levels. (Photo by Matt Cardy/Getty Images)

Kale grows at Kajodlingen farm in Gothenburg, Sweden, September 28, 2016. They are doing it on the rooftops, on tower block balconies and even on a disused railway: Swedes have discovered a passion for urban gardening as a way of growing fresh food and getting back in touch with nature. Part of a global movement, an increasing number of Swedish city-dwellers are growing their own in window boxes and allotments or are visiting public gardens built in or on industrial or office spaces. (Photo by Maxim Shemetov/Reuters)

Teeming with images of spectacular underwater scenes from around the world, Call of the Blue is the culmination of a five-year project by the photographer and ocean conservationist Philip Hamilton. This groundbreaking book includes contributions from acclaimed scientists and ocean “guardians”, who reveal what drove them to answer the call of the blue. (Photo by Philip Hamilton/The Guardian)

A Sumatran Tiger looks at visiting children from it's enclosure during the ZSL London Zoo's annual stocktake of animals on January 5, 2015 in London, England. The zoo's annual stocktake requires keepers to check on the numbers of every one of the 800 different animal species, including every invertebrate, bird, fish, mammal, reptile, and amphibian. (Photo by Dan Kitwood/Getty Images)

Urszula Sidoruk, 19, from the paramilitary group SJS Strzelec (Shooters Association), trains her workout at a gym in Siedlce, eastern Poland March 18, 2014. Inspired by the war in Ukraine, growing numbers of Poles are joining volunteer paramilitary groups, where they receive basic army training and prepare to defend their homeland. (Photo by Kacper Pempel/Reuters)

Family and friends sit in a vehicle trailer, where they will spend the night, near the enclosure for buffalos awaiting sacrifice on the eve of the sacrificial ceremony for the “Gadhimai Mela” festival in Bariyapur November 27, 2014. The festival renowned for its large number of animal sacrifices, is held every five years at the Gadhimai Temple where devotees from Nepal and bordering India will sacrifice buffaloes, goats and birds while offering prayers to Gadhimai, the goddess of power. (Photo by Navesh Chitrakar/Reuters)