Half lakes in world threatened by agricultural activities

More than half of the world's lakes are facing serious problems caused by agricultural activities, said Marion Hammerl, president of Global Nature Fund (GNF), on Wednesday.

Soil degradation, unsustainable water withdrawal for irrigation, eutrophication and pollution by pesticides were among the biggest dangers, she told the 11th International Living Lakes Conference in Nanchang, capital of east China's Jiangxi Province.

The deterioration of lakes had become one of the most critical challenges facing mankind, Hammerl said. The rapid development of agriculture and irrational uses of resources were the main causes.

Human mistakes included the excessive use of fertilizers and pesticides, over-irrigation, insufficient waste water treatment, land reclamation for farming and over-fishing, she said.

"Those who do not look wisely to the future will soon find problems close at hand," she said, adding that cleaning up rivers, restoring lakes and improving water quality were expensive.

"It is cheaper to prevent damage than to repair it," she said.

In addition to agricultural pollution, increasing population, industrialization and urbanization had a severe impact on lake biodiversity, she added.

She called for joint efforts by governments and international organizations to curb the "dangerous situation" of lake pollution and enhance protection of lakes and wetlands.

The international Water Association (IWA) estimates that in China, 340 million people, particularly in rural areas, have no access to clean drinking water.

China has only seven percent of the world's fresh water resources to meet 22 percent of the world's population, according to the IWA. There are 361,100 square kilometers of lakes and 90,000 square kilometers of wetlands in China, with a freshwater storage of 226 billion cubic meters.

Nearly 1,000 lakes have disappeared over the past 50 years, an average rate of 20 lakes lost each year, according to statistics of the State Environmental Protection Administration of China.

About three quarters of China's 20,000 natural lakes and thousands of artificial lakes suffered from algae pollution caused by an influx of waste water containing nitrogen, phosphorus and other harmful substances.

The IWA urged China and other developing countries to better protect lake ecosystems, which contribute to the formation of rain clouds, recharge groundwater reservoirs, boost evaporation and thus produce the cooling effects in summer.

During the two-day forum, the first of its kind in China, more than 200 participants will discuss sustainable lake management, avian influenza and wildlife habitat conservation.

The conference will also provide a platform for participants to share success stories of how to balance agricultural development and lake protection, according to GNF, the conference sponsor.

In 1998, GNF initiated the Living Lakes Network, which has 43 members, in order to enhance the protection, restoration and rehabilitation of lakes and wetlands.

Poyang Lake in Jiangxi, the largest freshwater lake in China, joined the Living Lakes Network in 2003.

Source:Xinhua