A shortage in the city's supply of donated blood has led the authorities to offer inducements to get people to give.

The Beijing Blood Center says it is receiving about 20 percent less blood than it needs, prompting it to offer regular donors the chance to make free medical appointments online and read nearly 1,000 magazines on the Web.

Foreign donors can also access the incentives.

The latest statistics show that the center's daily blood collection has fallen to 2,400 ml since last week, creating a 400-ml shortage in the amount needed each day for medical use.

Several local media outlets have reported that local authorities have started to limit hospitals' use and are calling on patients who are booked in for elective surgery to postpone the procedures in order to make sure there is enough blood for emergencies.

Liu Jiang, director of the blood center, said the hot weather is the main reason for the fall in donations.

Liu said 94 percent of donors decide to give blood on a basis and many are not choosing to give at the moment because they are less likely to go out during the hot weather. All of the capital's blood used in medical procedures has been supplied by voluntary donors since 2006.

Liu said supply tends to fall during the hot months of July and August and the cold months of December, January and February.

The center plans to update its official website and create an online membership system for blood donors. Donors will be able to register online to attend one of 63 hospitals, including 19 in Beijing. They will also be exempt from paying the 3-yuan online appointment fee, according to the center's news release on Monday.

In addition, the updated website is working with online reading websites and job-boards, so donors can browse nearly 1,000 best-selling magazines and search numerous recruitment sites for free.

"Our data shows that around 80 percent of the tens of thousands of blood donors we have are young - aged between 18 and 30 - and, in order to attract more of this group, we plan to provide the reading service and recruitment information," said Liu.

He said the center is also working hard to solve the recurring problem of blood shortages at certain times of the year and is installing minus-80-C storage facilities, so blood can be kept for up to 10 years.

Expatriates are welcome to donate blood and the center has "no limitations on the nationalities of donors," according to an operator on the center's hotline.

All would-be donors must first complete a medical examination and share relevant personal information.

"The process may take 45 minutes. If donors are English-speaking foreigners, they can ask for forms in English, which are available at almost all blood donation locations," said a hotline operator.

The donation sites are open from 8 am to 4 pm seven days a week.

"If you are foreign, please remember to bring your passport because we will need to register you."

Expatriates are treated the same as local residents and will get the same encouragement if they donate blood, according to the hotline.