On Saturday, Chen Qi, an undertaker from Dalian in Liaoning province, set sail for another sea burial. It was an especially busy day for Chen, whose ship was carrying 60 urns from Harbin, Heilongjiang province. Since 2009, 559 people from the inland northeastern city have had their ashes scattered at sea.

Chinese people often bury the ashes of deceased loved ones in time to pay tribute to them on Tomb Sweeping Day, which falls on April 4 this year.

Graveyards are always packed with people on the day, which is also known as the Qingming Festival, but increasing numbers are opting for sea burials in which ashes, often accompanied by flower petals, are scattered at sea.

"We have seen more families take part in sea burials in recent years," said Chen, who has been in the business for 19 years. "Their attitudes toward burials has changed."

Chinese people traditionally believed that souls only rest in peace if their bodies are covered by soil, which was also considered more respectful to the deceased. But attitudes are changing.

"Old people ultimately don't care how they are buried," said Weibo user "Kangzhuo". "What truly matters to them is the well-being of their children."

Chen said: "They've also realized that nobody will look after their graves when their children and grandchildren all pass away."

Having an environmentally friendly burial has become important to many.

"We all realize that sea burials do the least harm to our environment," said a woman surnamed Ren from Harbin, who attended the sea burial in Dalian to see off her late mother. "So we just decided to give up on the idea of buying a grave."