To prevent the deserts coming near, China has planted billions of trees—to replace destroyed forests and as barriers against the sand. This isn't a cure, though, say experts, as thirsty trees can make the problem worse by taking in groundwater.

    “Planting tress is one way, but it isn't that simple. It doesn't solve the basic issue of water resources,” says Wu Bo, a professor. “We need to calculate how much water the trees will absorb, or else it could have a negative effect.”

    Villagers in Zhengxin have taken on this challenge, with limited success. When the irrigation channels began to run dry, Lu Xianglin switched from wheat to cotton on his land. He also planted trees to protect his fields from sandstorms. He says he still gets good yields（产量） using flood irrigation and earns a good income for his family.

    Other farmers haven't stuck it out（坚持到底）: about one in three have left Zhengxin in the past 10 years after their wheat crops died. Young people who can find jobs in the towns rarely return.

    Last week, Mr Lu joined the other men in his village on a government-arranged trip to see the land that has been set aside for their relocation, nearly 40 miles to the south. The next day, he was back, shaking his head at the plan. The idea of uprooting his family troubles him, as does the idea of giving up the land that fed his forefathers. He prefers to stay and keep up the fight.

    “With enough water, this problem can be solved,” Lu says. “We can plant trees and grass, and they will grow bigger. That will stop the desert.”

    Experts say that farmers could switch to drip irrigation （滴灌）to lessen their water intake for growing crops. Elsewhere in the region, farmers have built brick greenhouses as part of a plan to grow vegetables using less water. Roadside signs urge farmers to “Save Water, Protect the Environment”.

   “One thing I enjoy about my job is that I can work on something that is actually active,” says Game McGimsey, an American volcanologist (火山学家). Part of his job includes keeping an eye on Alaska's many active volcanoes and giving people a heads-up when a volcano might erupt (喷发).

    Like most jobs in the sciences, volcanology requires a lot of education. McGimsey received an undergraduate degree in geology at the University of North Carolina, then landed an internship (实习期) with a geologist at the USGS (美国地质勘探局) whose area of expertise was volcanoes. After earning a graduate degree at the University of Colorado, McGimsey accepted a job with the USGS and has been with the Alaska Volcano Observatory for 25 years.

    Volcanoes can influence the world in ways we might not think about. For example, on Dec. 15, 1989, a 747 jetliner (a large airplane) flew through a thick ash (灰) cloud produced by Mount Redoubt, an Alaskan volcano that hadn't erupted in 25 years. The ash caused all four engines to die, and the plane's electronics went dead.

    “The plane was within several thousand feet of flying into the mountains below when the pilots got a couple of the engines restarted and landed safely in Anchorage,” McGimsey says. It cost nearly $80 million to repair the damage to the plane.

    Such situations show just how dangerous volcanoes can be. However, volcanologists know the risks and are prepared to protect themselves.

    “There is certainly a higher danger level in volcanology than some other jobs,” McGimsey admits. “We understand how serious the danger is, and we don't like taking unnecessary chances. We avoid getting too close to an erupting volcano, because it's not worth injury or death simply to get a rock or a photograph.”

    There are countless short videos on YouTube. It's a website for people to post video made by themselves. Many people make a lot of money through doing so. Then, who made the most over the past year?

    YouTube's top-earning celebrity is a 25-year-old video-game-playing young man who shows a strong sense of humor in his videos. He earned $12 million over the past year. Forbes magazine says Sweden's Felix Kjellberg, better known by his handle "PewDiePie", tops its first list of people who have turned short videos into huge piles of cash.

    YouTube stars make money mainly by getting paid to interact with products on their channels and sharing ad revenue(收入) with YouTube. Some also star in movies, write books, go on tour, or sell music. They're a hit with younger audiences and brands trying to reach the next generation of consumers.

    Two acts tied for the second place on Forbes' list, both earning $8.5 million: comedy prankster(搞恶作剧的人) duo Smosh(Ian Hecox and Anthony Padilla) and the Fine Brothers(Benny and Rafi Fine). Dancing violinist Lindsey Stirling ranked fourth with $6 million. Tied for fifth were comedians Rhett and Link(made of Rhett McLaughlin and Charles Lincoln III) and video game commentators(解说员) Olajide Olatunji, known as "KSI," with $4.5 million. Make-up artist Michelle Phan was seventh at $3 million. The No. 8 place was a three-way tie at $2.5 million shared by comedian Lilly Singh, or "Superwoman;" prankster Roman Atwood; and chef Rosanna Pansino.

    Forbes is best known for its list of billionaires and this list marks its first attempt at ranking YouTube stars. It says it measured earnings before management fees and taxes and came up with the figures based on data from online sources such as Nielsen, IMDb and interviews with managers, lawyers, industry insiders and the stars themselves.

    Welcome to SummerCamps.com; find and book the very best summer camps. Your children are precious so we offer the highest quality of camps that will meet each child's needs and interests.

    Catalina Sea Camp

    Sea Camp offers three one-week sessions to boys and girls aged 8-13 and two three-week sessions to teens aged 12-17. Our hand-picked instructors create an atmosphere of fun and excitement while leading campers to a host of ocean adventures, marine(海洋的) biology, and social summer camp activities.

    Address: Toyon Way, San Bruno, California 94066

    Phone: 800-645-1423

    Camp Cayuga

    Camp Cayuga is a private summer camp for children aged 6 to 16. The camp is on a 350-acre land in the Pocono Mountains of Northeast Pennsylvania, just outside the village of Honesdale. It's a 3-hour drive from New York City and Philadelphia.

    Address: 321 Niles Pond Road-Suite ISC, Honesdale, Pennsylvania 18431

    Phone: 908-470-1224

    Camp Rockmont

    Camp Rockmont is a Christian summer camp for boys, aged 6-16, in the Blue Ridge Mountains of North Carolina. Rockmont's duty of developing boys into healthy young men is accomplished through age-appropriate skills, activities, and challenges that help campers to know themselves better.

    Address: 375 Lake Eden Road， Black Mountain, North Carolina 28711

    Phone: 828-686-3885

    Primitive Pursuits Overnight Camps

    Primitive Pursuits Overnight Camps offer week-long Summer Adventure Overnight Camps in New York's Finger Lakes to your children aged 11-15. Campers experience a week of nature-based skills training, inspiring challenges, and fun activities under the guidance of skilled instructors.

    Address: 611 County Rd 13, Van Etten, New York 14889

    Phone: 607-272-2292

    When I was six, Dad brought home a dog one day, who was called “Brownie". My brothers and I all loved Brownie and did different things with her. One of us would walk her, another would feed her, then there were baths, playing catch and many other games, Brownie, in return, loved each and every one of us. One thing that most touched my heart was that she would go to whoever was sick and just be with them, we always felt better when she was around.

    One day, as I was getting her food, she chewed up(咬破)one of Dad's shoes, which had to be thrown away in the end. I knew Dad would be mad and I had to let her know what she did was wrong. When I looked at her and said, "Bad girl," she looked down at the ground and then went and hid. I saw a tear in her eyes.

    Brownie turned out to be more than just our family pet, she went everywhere with us. People would stop and ask if they could pet her. Of course she'd let anyone pet her. She was just the most lovable dog. There were many times when we'd be out walking and a small child would come over and pull her hair. she never barked(吠) or tried to get away. Funny thing is she would smile. This frightened people because they thought she was showing her teeth. Far from the truth, she loves everyone.

(Now many years have passed since Brownie died of old age. I still miss days when she was with us.)

    Bedtime on the Orient Express. We stood in the corridor while a woman pulled our bunk beds (双层铺) into place-- there wasn't room in the carriage for all three of us. Barking the news that she would be waking us at 7 a.m. with a cup of instant coffee and a piece of cheese, the woman left and we retired for the night.

    'Bunk beds?' you may be thinking. Small carriage? Instant coffee? This can't be the real Orient Express! Oh, but it is. This is a very real Orient Express indeed. In search of a long weekend in Vienna, there seemed no more attractive way for my friend and me to get there.

    The original Orient Express service was started in 1863. Luxury carriages ran the route from Paris, France to Giugiu, Romania. In 1934, Agatha Christie sent Hercule Poirot on just such a journey in her novel Murder on the Orient Express. However, there was a rise in air travel which was quicker and cheaper and eventually the whole operation was brought to a halt in 1977. The name was reused in 1982, when the Venice Simplon-Orient-Expresss took its first voyage between London and Venice.

    Admittedly I would have loved to take the Venice Simplon-Orient-Express, with its on-board shop and piano in the bar, but at around £1,700 per person for a four-night one-way journey, it was too expensive for us. So we chose this excellent way of buying into the romance for a small amount of the cost.

    But we loved it. Ours was no luxury bedroom, but it had its own rough charm-- not to mention the magic of travelling across international borders overnight. I haven't slept in a bunk bed since I was seven, and climbing up into it took 25 years off me. For one night only, it was comfortably appealing. Naturally, I took a copy of Murder on the Orient Express to read on the train. I smiled at the descriptions of airy dining cars and fresh coffee.

    My weekend in Vienna was wonderful and reunited with the cut-price Orient Express at the end of the holiday, we were rather delighted to see our little carriage again. Good old bunk beds. Terrifying old attendant. And best of all, nobody got murdered.