Since the 1980s, a number of laws have been made or amended to officially recognize farmers' rights to use or circulate the land they have contracted.

A law adopted in 2003 provided clear guidelines on the use of contracted farmland, including subcontracting, leasing, exchange or transfer.

In recent years, the government has called for deepening reform of the land system in rural areas to give farmers more rights - in particular, the right to make greater use of land they have contracted.

In 2014, for example, provinces, autonomous regions and municipalities began issuing certificates to farmers.

The certificates provide information about land they have contracted, such as dimensions and boundaries, along with identification details to facilitate subcontracting. Almost everyone who contracted farmland was expected to have received a certificate by the end of last year.

As a result, more farmers have leased their land to others, or used it as security for loans, bringing more profits.

Meanwhile, greater circulation of land has promoted consolidation of small plots into sizeable blocks, and facilitated the development of modern agriculture in many regions.