WUHAN - A survey has shown that the already-yawning wealth gap among different regions and industries in China is widening, with nearly 50 percent of the gaps resulting from rural-urban disparities.

The survey, which was conducted by the Income Distribution Research Center affiliated with the Zhongnan University of Economic and Law, showed that the wealth gap among rural residents is expanding.

A green book published Wednesday by Social Sciences Academic Press suggested that incomes for rural Chinese grew faster than those of their urban counterparts for the last three years.

However, the gap among rural residents is larger than that of the urbanites, according to the survey.

Chinese urban residents earned 24,565 yuan ($3,967) in annual per capita income in 2012, while rural residents earned 7,917 yuan in per capita net income.

The survey noted that developed regions in east China had the smallest income gap, followed by the relatively underdeveloped central and western regions.

People engaged in social services and agriculture-related work earned the lowest average wages, while those working in the electric power, communication, finance and insurance industries had the highest salaries, according to the survey.

The survey said authorities should make more efforts to adjust the income redistribution system.