The two hectares of land covered with black soil that were once the pride of farmer Lei Guangsheng are now a problem without an easy solution.

"The soil is becoming harder and less productive," said the 62-year-old of Dongling Village in Northeast China's Jilin Province.

Per-hectare corn output is approximately 23 tons, seven tons less than five years ago, Lei complained.

But there is help on the way, as the Ministry of Agriculture has launched a massive drive to help farmers test the quality of their soil before applying the correct amount of fertilizer, division director Chen Mengshan said.

The central budget has earmarked 500 million yuan (US$61.65 million) this year to cover the cost of testing farmland soil, he said.

The funds will be used to give localities special equipment and subsidize efforts to apply the right amounts of fertilizer, the official said.

In many regions, soil degradation is largely attributable to the irresponsible use of fertilizers, according to Jiang Yalun, a senior agronomist in Jilin.

He said farmers mostly use only one kind of chemical fertilizer for several years in a row, without testing what elements the soil actually lacks.

In Lei's village, most farmers fertilized the soil with farmyard manure 10 years ago, but now most have opted for chemical fertilizers.

However, it seems that each year, the more chemical fertilizers are used, the poorer the soil is, Lei said.

Over the past five decades in Jilin, dubbed "the granary of China" for its large areas of fertile and productive black soil, 34 per cent of its prime farmland has been eroded, and the black soil layer has been reduced by 50 per cent, according to a report released by the Chinese Academy of Engineering.

"If the deterioration cannot be halted in time, sustainable development will be gravely affected in the region," Xinhua quoted the report as saying.

With the launch of soil testing, the Ministry of Agriculture expects to improve the quality of the country's farmland by increasing the use of organic fertilizers.

It also hopes to use a better mix of nitrogen, phosphorus, kalium and microbe fertilizers, Chen told China Daily.

Areas, including some in Northeast China, will carry out pilot projects in which at least 18.67 million hectares of farmland will be tested to see what exactly the soil needs in order to improve yields, he said.

Agricultural technicians will go to each farm in pilot areas, advising them how to apply fertilizers in the most efficient and scientific way.

Experts say such efforts will also help cut agricultural production costs because many farmers, as in Lei's case, often use too much fertilizer, which costs a lot of money.

"The decline in soil conditions is inevitable once it is turned from its natural state into arable land," said Han Xiaozeng, a researcher with the Northeast Institute of Geography and Agricultural Ecology, which is based in Harbin, capital of Northeast China's Heilongjiang Province.

"What we can do is to slow down that process," he said.

Han proposed allowing natural vegetation to return to farmland on steep slopes, and rotating grass and grain crops.

"If properly treated and fertilized, soil can even be improved year by year," he said.

Source: China Daily