China has toiled over the last few years to restore and preserve its wetland resources, the largest in Asia and fourth largest in the world. Often referred to as the world's "kidneys," the areas were for a time endangered by its rapid agricultural growth.

Excessive cultivation once reduced China's largest marshland area by more than 3 million hectares (7.4 million acres), or two thirds, on the Sanjiang (Three Rivers) Plain, an area between the Songhua, Nenjiang and Heilong rivers in the country's northernmost Heilongjiang province. China plans to have ruined wetland areas reclaimed by 2020.

In 1999, the local government banned any cultivation and excavation on the Sanjiang Plain and set up a wetland preservation zone that has since become "paradise regained" for rare species such as gray cranes and red-crowned cranes.

In the wake of the disastrous floods that deluged many Chinese provinces in the summer of 1998, officials in the drainage area of Dongting Lake, a large freshwater lake in the middle reaches of the Yangtze River, started a "grain for water" program to increase the lake's water storage and prevent future floods.

"All these changes show that China is set to contribute tremendously to the protection of wetlands and ecological systems," said Yin Hong, an official with the State Forestry Bureau, at an international conference on wetland studies held recently in Nanjing.

Yin and his colleagues have worked to ensure China's fulfillment of the Convention on Wetlands, an international convention designed to protect waterfowl and wetland resources, which China entered into in 1992.

The wetlands earned their nickname "kidneys" because of their vital role in water conservation and the prevention of erosion and flooding.

However, their importance has not always been appreciated. A great deal of suffering came to the lands at the time when the country held that natural wetland -- 65 million hectares (160.5 million acres) of wetland, about 10 percent of the world's total -- was "waste land" and listed it as reserved resources for agricultural purposes.

Decades of cultivation reduced China's lake coverage by 1.3 million hectares (3.1 million acres) -- about 20 lakes every year, an official in charge of wetland preservation revealed at the conference.

Meanwhile, excessive cultivation caused half of the country's mudflats to disappear and worsened water pollution in major lakes and rivers.

In addition, experts say that floods, droughts, red tides and sandstorms that have afflicted north China frequently in recent years, are also closely related to the shrinkage of natural wetlands, which can store excess water to control floods, and purify water and soil.

Previous statistics show that related ecological damage caused economic losses equal to four to eight percent of China's gross national product.

Waking up to the disastrous consequences, in 2000 the Chinese government implemented an action plan for protecting China's wetlands, and the Ministry of Agriculture decided that natural wetland would be removed from the list of reserved arable land resources.

According to the action plan, China will work out a legal system for wetland protection and set up an advanced monitoring network for the wetland ecological system. By 2010, it will curb wetlands degradation caused by human activities and reclaim most natural wetlands by 2020.

To achieve this goal, China has so far invested 19.9 million yuan (US$2.4 million) to return farmlands and pastures to wetlands, restore mangroves -- believed to be natural protectors of maritime environment -- along rivers and lakes, and set up wetland preservation zones, which had totaled 353 by June 2002.

Today, 3.03 million hectares (7.5 million acres) of wetlands in China have been listed as major wetland areas of the world.

Residents in these areas, now convinced of the importance of their resources and the ecological environment, are standing behind the government.

"In the past, farmers on the Sanjiang Plain used to flock to the marshland in spring picking jars of mallard eggs," said Tong Shouzheng, a local scientist for agricultural ecology studies. He added that "only very few people do this today."

(Xinhua News Agency September 28, 2002)