The heart of a city to some people is the central business district where people live in the hustle and bustle.
Or to others it can be the architecture of various landmarks which to them embody the city's spirit. But in Guangzhou, its people call an area of wetlands their "green heart".
On sunny weekend mornings, when the mists over Haizhu Lake gradually disappear, it is easy to spot birds spreading their wings and flying high into the sky.
Haizhu Lake is a part of Guangzhou Haizhu National Wetland Park. With an area of 1,100 hectares, the wetland is one of the largest downtown wetland parks among China's super metropolises.
It is located in the southern part of the central axis of Guangzhou. When the weather is good, people can spot the city's landmark, Canton Tower, from the wetlands.
As a typical urban lake and riverine wetland in the Pearl River, the water brought to the wetlands by the ebb and flow of the tide is purified by the wetland, which showcases wetland areas' function as "the kidney of the Earth".
It also provides an important stopover and wintering site for migratory birds that pass over the Pearl River Delta.
Known as the Gigantic Orchard, the wetlands produce beautiful star fruit, which serves as a delicacy for the birds.
After the wetland park was open to the public, it became a hot spot for citizens living in the urban area.
The wetland park was awarded the Model Prize of China Habitat Environment in 2016, in appreciation for its contribution to preserving the local ecology and improving the environment.
According to the administration of forestry and gardening in Guangzhou municipality, at present there are a total of 19 wetland parks in the city.
These range from coastal wetlands and urban or countryside wetlands, to riverine or wild field wetlands. Seven of them were newly established this year.