While few would question the need for chemical fertilizers in China, the real need is for its effective use to prevent environmental damage, experts say.

In the wake of a recent survey, which points to a lack of knowledge among the country's farmers, experts are calling for more education and environmentally-friendly farming.

"We can produce enough food to feed the country's growing population by improving soil fertility and plant nutrition with chemical fertilizers," said Cheng Xu, a professor with the China Agricultural University. "Otherwise, more land will be cultivated and the risk of erosion from wind or water increased."

However, chemical fertilizers are a double edged blade. If misused, they can severely harm the environment, Cheng said yesterday.

Agricultural experts participated in the annual meeting of the non-governmental advisory body China Council for International Cooperation on Environment and Development late last month in Beijing. Experts agreed that more than half of the nitrogen-based fertilizer used in China flies off with the wind or runs off when fields are watered.

The health of millions of people in 13 provinces and regions in the country has been threatened by fertilizer pollution, which mainly contaminates water sources.

A recent survey shows Chinese farmers still lack basic knowledge of how to use fertilizers effectively.

A survey released by the China Consumers' Association last week found that more than one third of surveyed farmers misuse chemical fertilizers, while even more lack basic knowledge about the product they are using.

Agronomists say different plants and crops need different fertilizing measures including deep ploughing after fertilizing and dissolving before applying.

And more than 45.9 percent of respondents said they do not know about balanced fertilizing measures.

Balanced fertilizing, consisting of slow release of nitrogen, potassium and phosphorus, has been promoted by experts in rural areas in recent decades.

In Tongxiang of east China's Zhejiang Province, an eco-construction program has been introduced to maximize use of resources and minimize pollution.

(China Daily November 2, 2004)