A combination photo shows the Kremlin, the GUM department store and the St. Basil's Cathedral before (top) and during Earth Hour in Moscow on March 27, 2021. [Photo/Agencies] GENEVA -- As lights around the world turn off at 8:30 pm local time on Saturday to mark Earth Hour 2021, World Wildlife Fund (WWF) International calls for urgent action to turn the tide and secure a nature-positive world by 2030, while raising hopes the COP15 biodiversity conference to be held in China could become the next "Paris Agreement for nature." This year's event shines a spotlight on the perilous state of the planet, urging individuals, leaders and environmentalists to set nature on the path of recovery. "This is the time to unite people, to speak up for nature," WWF International Director General Marco Lambertini told Xinhua in a recent interview.