Beijing —- For a nation that desperately wants to get the Olympics right, many things are going wrong.

Just over a month before the Aug. 8 opening ceremony for the Summer Olympics in Beijing, tens of thousands of Chinese are battling a plague of locusts and a spreading bloom of bright green algae covering the Olympic sailing course.

In Beijing, hoteliers are worried that tight visa restrictions have discouraged tourism and profits during the Games could be far below an expected windfall.

The problems —- some seemingly biblical, some clearly man-made —- have distracted from gargantuan efforts by Beijing to host a spectacular Games. China has spent a record $37 billion to prepare for the Olympics, an amount four times more than Athens spent on the 2004 Summer Olympics. The money has gone for new subway lines, an airport terminal and more than three dozen new and refurbished sports venues.

On Wednesday, hundreds of laborers scrambled to finish work at the Olympic Green, a milelong strip that will be the Games' epicenter. The only major structure still under construction —- a 525-foot-tall broadcasting tower wedged between China's National Stadium and National Aquatics Center —- will be finished by July 15, said Wang Guanghai, a security manager at the site.

Qi Dan, a university student visiting Beijing from central China, peered through a security fence and said "every Chinese person is excited that we are hosting the Olympics. It means we have really become part of the world."

But if the Games will highlight China's growing global prominence, it will also throw a harsh spotlight on problems caused by China's rapid development and slow political opening.

The 154-square-mile algal bloom off the coast of Qingdao, a city on the Yellow Sea southeast of Beijing, and a plague of millions of locusts in northern China have underscored how the country's environment has suffered from pollution and overuse.

While at least one Chinese official has called the algae outbreak a "natural disaster," a biologist at Shanghai Fisheries University said the algae had multiplied because pollution from nearby factories and many fish farms along the coast had "destroyed the natural balance."

Wu Jichuan, a retired entomologist at the Chinese Academy of Sciences in Beijing, said the locust infestation —- which Beijing is battling with 33,000 exterminators and 200 tons of pesticide, according to state media —- is linked to China's deteriorating environment because locusts breed more rapidly in dry areas with little natural vegetation. Grasslands in Inner Mongolia, the center of the outbreak, have been heavily damaged in recent years by farmers overgrazing their livestock.

The Games also have highlighted Beijing's strict social controls.

China has tightened visa restrictions, including limiting multiple-entry visas and requiring applicants to show hotel bookings and return plane tickets. And some people working for activist groups have been denied visas for the Games, said Nicholas Bequelin, a Hong Kong-based researcher for Human Rights Watch.

The stricter laws also have deterred some tourists. Chinese officials have said they expect 1.5 million visitors to the city during the Games. But Beijing's Tourism Bureau said in May that only 77 percent of five-star hotel rooms and less than half of four-star hotel rooms had been booked. And Wang Rui, a saleswoman at the five-star Yuyang Hotel in downtown Beijing, said on Friday only 40 to 50 percent of that hotel's rooms had been reserved.

Visitors who do travel to Beijing can expect increased scrutiny.

China will deploy 80,000 police, soldiers and guards during the Games and has mobilized hundreds of thousands of citizens to monitor people considered security risks, Bequelin said.

"There is a very, very large surveillance network [in Beijing]," he said. "If there is a protest it will be stopped within minutes if not seconds."

The city will force many factories to close during the Olympics. And to reduce traffic congestion and air pollution, half of all private cars will be banned from July 20 until Sept. 20, three days after the closing ceremony of the Sept. 6-17 Paralympic Games.

"The government wants to make things easier for visitors, but their restrictions are too severe," a taxi driver surnamed Wang said as he drove through a street packed with pedestrians, cars and cyclists this week.

Like most Chinese, however, he welcomed the Olympics as an opportunity for Beijing to engage with the world.

"Everyone will be able to learn more about China," he said.