BEIJING - China vowed to renew its efforts to improve agriculture through science and technology as part of a major effort to boost the country's agricultural production and increase farmers' incomes, a central policy document said.

Developing agricultural technology is the core issue to ensure the quality and safety of agricultural products, according to this year's No 1 document issued by the Central Committee of the Communist Party of China (CPC) and the State Council on Wednesday.

The central authorities regularly release a major policy document at the beginning of each year to address government priorities.

This is the ninth consecutive year that the first document has been themed on rural issues.

China will also quicken the pace of constructing water-conservation facilities, treat rivers and lakes, strengthen reservoirs, prevent geological disasters and increase the areas that have access to irrigation, the document said.

Similarly, the document said the country will push for agricultural mechanization by boosting credit support for the purchase of machinery.

It also pledged to launch key ecological projects in the country.

With 9 percent of the world's arable land being used to feed 22 percent of the world population, China's achievements and contributions to world food security are universally recognized.

The country's grain output hit 571 million tons in 2011, a 4.5 percent year-on-year increase and the eighth consecutive year of growth, statistics from the National Bureau of Statistics showed.

The latest harvest exceeded the nation's plan to boost the annual grain yield to 550 million tons by 2020.

Meanwhile, the output of all major agricultural products in China has increased in 2011, for the first time in 16 years, Minister of Agriculture Han Changfu said at the central government's conference on rural work in December.

Analysts and senior officials said that the country must boost technological inputs into agricultural production to counter food demands of a growing population and the shrinkage of arable land, which is being lost to rapid urbanization.

"China is now leading the world in some fields of agricultural technology, such as cultivating grain seed varieties," said Li Maosong, director of the Chinese Academy of Agricultural Sciences' agriculture information office.

Meanwhile, the country lags behind in many other fields, compared with the United States and some European countries, including corn and vegetable production, and raising livestock and poultry, he said.

Li said the country will show strong demand for top-quality seed varieties, such as anti-drought and pest-resistant seeds, and advanced cultivation methods in the next few years to improve unit yield and the quality and safety of agricultural products.

Also, statistics from the National Bureau of Statistics showed that urban residents accounted for 51.2 percent of the population in 2011, surpassing 50 percent for the first time, meaning more rural labor was being lost, analysts said.

"Major efforts will be strengthened to provide more educational training on science and technology in the rural areas to produce professionals in the sector to facilitate production growth," Chen Mengshan, chief economist of the Ministry of Agriculture, was quoted by Xinhua News Agency as saying on Wednesday.