The central authorities Tuesday issued guidelines on an ecological “red line” that will declare certain regions under mandatory and rigorous protection.

The document was jointly issued by the General Office of the Communist Party of China (CPC) Central Committee and the General Office of the State Council.

By the end of 2020, according to the document, China should have clearly defined the “red line.”

Given that China’s ecological environment remains fragile and the environmental safety situation is pretty grim, the ecological “red line” serves as both a “bottom line” and a “lifeline” in safeguarding national ecological safety, according to the document.

The “red line” strategy will cover regions with important ecological functions, including water and soil conservation, biodiversity maintenance as well as windbreak and sand-fixation, along with ecologically fragile regions which are prone to soil erosion, desertification and salinization.

The guidelines asked Beijing, Tianjin and Hebei, as well as regions along the Yangtze River Economic Belt to draw up a “red line” for ecological protection by the end of 2017, while other areas should come up with a “red line” before the end of 2018.

By the end of 2020, the demarcation of the border and calibration of the regions should be completed and an ecological protection “red line” system will be basically established.

By 2030, the layout of the ecological protection “red line” will be further optimized, effectively implemented, the ecological function of the regions promoted, and national ecological safety guaranteed, according to the document.

The move aims to ensure protected regions will not be ecologically degraded, and their acreage will not be decreased.

“China started to explore the theory and methods of the ‘red line’ in 2012 and made a series of pilots programs,” said Lu Jun, deputy head of the Chinese Academy for Environmental Planning.

China’s environmental protection still lags behind its economic status, and decades of breakneck growth have left the country saddled with problems such as smog and contaminated waterways and soil.

In one of its latest attempts to fight pollution, China appointed “river chiefs” nationwide in December.

China detained 720 people for environment-related crimes in 2016, according to the national environment work conference in January.

Through public tip-offs and random checks, inspectors looked into 33,000 cases and imposed fines totalling 440 million yuan (about 63.6 million U.S. dollars) after central government inspections in several provinces and municipalities, including Beijing and Shanghai.

Last year, a total of 4.05 million high-emission vehicles were taken off the country’s roads.

Partly due to such efforts, Chinese cities reported less PM2.5 pollution in 2016, with the average density of PM2.5 in 338 cities falling by 6 percent. Meanwhile, days with good air quality rose 2.1 percent from a year ago.

The central authorities handled 11,735 suggestions and proposals submitted by legislators and political advisors in 2016, over 90 percent of all of those submitted.

Xi Yanchun, spokeswoman with the State Council Information Office said at a press conference on Tuesday that State Council departments had responded to 7,873 suggestions raised by deputies to the National People’s Congress and 3,862 proposals put forward by members of the National Committee of the Chinese People’s Political Consultative Conference during the annual sessions of the two bodies held in March 2016.

This means that 91.5 percent of the national legislators’ suggestions and 90.9 percent of political advisors’ proposals put forward during the two sessions were handled by the central authorities, Xi said.

More than 3,000 suggestions and proposals had been adopted by State Council departments and over 1,300 policies and measures have been introduced accordingly, Xi said, adding that the process had improved the quality of government decision-making.

The Ministry of Education (MOE), which handled 1,023 legislators’ suggestions and 805 political advisors’ proposals, introduced 81 new policies in 2016, most of which were inspired by the suggestions and proposals, according to Shen Xiaoming, vice minister of the MOE, at the briefing.

Issues of top concern last year included student life, educational equality and development of higher education, Shen said.

Inspired by the suggestions and proposals, the National Health and Family Planning Commission issued a guideline on what it calls “Healthy China,” with more than 20 other authorities, and launched an action plan to improve medical services, according to Cui Li, deputy director of the commission, at the briefing.

Beijing police announced Tuesday that 77 suspects had been arrested in connection to organized prostitution.

After a raid on Dec. 23, 2016 at three alleged brothels that were operating as entertainment venues, the police submitted an arrest request to the procuratorate so that those linked to organized prostitution could be detained for questioning.

The arrest warrant was approved on Jan. 26, 2017, and the investigation continues.

Nanjing of East China’s Jiangsu province will become the third city in the world where Italian architect Stefano Boeri will build Vertical Forest buildings, which could possibly improve the city’s air quality, according to CNET, an American media outlet on technology.

In architect Boeri’s design, a set of two towers will be stylized with around 1,100 trees and a combination of over 2,500 shrubs and plants, which is believed to make 60 kilograms of oxygen every day by absorbing carbon dioxide.

The two towers are expected to be completed by next year and will stand at 107m and 199m tall respectively. The shorter building will house a Hyatt hotel, while the taller one will be home to a museum, offices and an architecture school.

Two previous vertical forest buildings were built in Milan, Italy, and Lausanne, Switzerland.

Boeri’s plan in China is much more ambitious as similar structures are also planned for Shanghai, southwestern Chongqing, northern Shijiazhuang and southern Liuzhou.

A suspect who allegedly offered student loans in exchange for nude photos was arrested by police in Gansu province in January.

Authorities said the man, surnamed Yang, had been preying on young women who were in need of money for college and other expenses, seeking his victims through social media, and that he had been doing this activity for many years.

Female students were ordered to disrobe and hold up their personal identification cards for photos before they were provided with high-interest student loans.

The young women were told the photos would be published if they failed to pay off their debts.

Yang also allegedly asked for sexual services from women who were unable to pay their loans.

Yang was arrested after a victim reported her case to the police. JD Capital’s Jiedaibao, a platform for individuals to loan and lend, especially between friends and acquaintances, was apparently used several times to set up transactions between perpetrators and victims in similar cases.

Jiedaibao said the company has no control over demands for collateral as such practices are made by a lender as part of “a private trade deal.”

Users who were asked for nude photos in exchange of loans are encouraged to contact the police.

To better protect the interests of its users, Jiedaibao’s customer service department established a one-million-yuan fund to combat the “naked loans” issue.

The company also said it would work with the police on any investigation of such practices.