It also reveals the scale of what some have called Beijing's escalating ­soft-power "charm offensive" to secure political and economic clout on the continent.

The Chinese government releases very little information on its foreign aid activities, which remain state secrets. In one of the most ambitious attempts to date to chip away at this secrecy, United States researchers have launched the largest public database of Chinese development finance in Africa, detailing nearly 1700 projects in 50 countries between 2000 and 2011.

China's financial commitments are significantly larger than previous estimates, though still less than the estimated $90-billion the US committed over that period. Researchers at AidData, at the College of William and Mary, have spent 18 months compiling and encoding thousands of media reports to construct the database. The data, which challenges what has for years been the dominant story – Beijing's unrelenting quest for natural resources – is likely to fuel ongoing debate over China's motives in Africa.

There are few mining projects in the database and, though transport, storage and energy initiatives account for some of the largest sums, the data also reveals how China has put hundreds of millions of dollars towards health, education and cultural projects.

In Liberia, it has put millions towards the installation of solar traffic lights in Monrovia and financed a malaria prevention centre. In Mozambique, its projects include a National School for Visual Arts in Maputo. In Algeria, construction has begun on a 1400-seat opera house.

China has also sent thousands of doctors and teachers to work in Africa, welcomed many more students to learn in China or in Chinese language classes abroad and rolled out a continent-wide network of sports stadiums and concert halls.

"The dominant narrative has been one of China's insatiable desire for resources. But this database suggests there may be more things going on," said Vijaya Ramachandran, senior fellow at the Washington DC-based thinktank Centre for Global Development and co-author of a report on the AidData project.

Only a fraction of the database's projects (totalling $16-billion) would count as official development assistance under the rules set by the Organisation for Economic Co-operation and Development (OECD). Ramachandran, however, insists China is still playing an important role in closing funding gaps in Africa.

While aid from OECD countries stagnates or shrinks under the pressure of budgets and an increasingly sceptical public, a host of new emerging donors – including Brazil, Venezuela and Iran – are expanding their work in other developing countries. They have largely resisted calls to disclose data or abide by international aid transparency standards.

This lack of information has fuelled speculation over what the donors are doing – and why. Many of the cultural and sporting projects across the continent are probably "upfront sweeteners" to win government favour, suggests Stephen Chan, professor at the School of Oriental and African Studies in London. But he rejects the idea that China has a master strategy in Africa.

"There are 54 countries in Africa. You're off your head if you think there's one single agenda."

Deborah Brautigam, head of the international development programme at Johns Hopkins University, said: "There are a lot of reasons countries give aid, and China is no different." – © Guardian News & Media 2013

Winning hearts and minds, then business and influence

China has been courting Robert Ochola with the awkward intensity of a high-school romance.

First it granted the 36-year-old Kenyan agricultural official a full scholarship for a three-year ­master's degree in Beijing. Then came the comfortable dorm room, the snazzy banquets and the complimentary Peking opera tickets. "Sometimes it's a bit too much," Ochola said, smiling.

Last year, then Chinese president Hu Jintao announced an aid programme that would offer 18 000 government scholarships and train 30 000 Africans "in various sectors" by 2015. Ochola is one of 63 government officials from Kenya to benefit from this.

Chinese training programmes vary in type and duration, from three-week political tours to advanced degree programmes.

China advertises these programmes as a kind-hearted diplomatic gesture – the terms "equality", "all-round co-operation" and "mutual gain" pepper its state media reports and programme descriptions. Experts say they're a calculated long-term investment to win the hearts and minds of Africa's future leaders, many of whom fear China's investment in the continent may come with invisible strings attached.

"Don't forget that people who are coming on these courses have only seen a tiny part of what China does," said Kenneth King, a professor emeritus at the University of Edinburgh and the author of a forthcoming book about China's soft power in Africa. "They've seen China building roads in Ethiopia, or building dams in many other countries. But they haven't seen a Chinese university, for example. They haven't seen a Chinese vocational school or a hospital."

Ochola is adjusting to life in China. He spends most days studying Chinese language, economics and maize-growing. Though he's awed by the gleaming skyscrapers and well-organised institutions, its dismal environmental record and tight political control give him pause. "If they were to go for a less restrictive system, I think the ­benefits would be better."

Many African officials see China's developing status as part of its appeal – something they can relate to, said Meng Bo, an assistant dean at the prestigious Tsinghua University school of public policy and management in Beijing. Tsinghua has offered a one-year English-language master's programme for officials from developing countries since 2008 and, until this year, about 80% of its students have been from Africa

Mahamat Adam, a Cameroonian business consultant and former member of the China-Africa Business Council, is wary. "It must be understood by the Africans: they are not there to do philanthropy, they are there to do business. The Chinese are here to work for us, but they're here for their own interests first." – © Guardian News & Media 2013