阅读图文材料，回答下列问题

材料一：贵州自然灾害频发，主要有干旱、冰雹、洪涝、雪灾、冰冻、滑坡、泥石流、坍塌等，给农业生产和人民生活造成不利影响．

材料二：石漠化的形成有自然原因和人为原因．山高坡陡，气候温暖、雨水丰沛而集中，为石漠化形成提供了侵蚀动力和溶蚀条件．过度樵采、不合理的耕作方式、乱砍滥伐、乱放牧、过度开垦是石漠化形成的主要原因．“石漠化”发展最直接的后果就是土地资源的丧失．又由于石漠化地区缺少植被，不能涵养水源，往往伴随着严重人畜饮水困难．

材料三：把石漠化治理与退耕还林、防护林建设、水土保持、人畜饮水、扶贫开发等生态工程有机地结合起来加以综合防治．如封山育林、荒山造林、退耕还林、转变群众生产生

活方式、实施生态移民等；尤其是要重视调整石漠化地区能源结构，加快农村能源建设步伐，减少森林资源的能源性消耗；调整种植业结构，发展林果业、木本粮油．

C

    Fat and shy, Ben Saunders was the last kid in his class picked for any sports team. “Foothall, tennis, cricket-anything with a round ball, I was useless,” he says now with a laugh. But back then he was the one always made fun of in school gym classes in Devonshire, England.

    It was a mountain bike he received for his 15th birthday that changed him. At first he went biking alone in a nearby forest. Then he began to-ride the bike along with a runner friend. Gradually, Saunders set up his mind on building up his body, increasing his speed and strength. At the age of 18, he ran his first marathon.

    The following year he met John Ridgway and was hired as an instructor at Ridgway's school of adventure in Scotland, where he learnt about Ridgway's cold-water exploits. Greatly interested, Saunders read all he could about North Pole explorers and adventures, then decided that this would be his future.

    In 2001, after becoming a skillful skier, Saunders started his first long-distance expedition towards the North Pole. It took unbelievable energy. He suffered frostbite, ran into a polar bear and pushed his body to the limit, pulling his supply-loaded sled（雪橇）up and over rocky ice.

    Saunders has since become the youngest person to ski alone to the North Pole, and he's skied more of the North Pole by himself than any other British man. His old playmates would not believe the change.

    Next October, Saunder, 27, heads south from the coast of Antarctica to the South Pole and back, a 2900-kilometer journey that has never been completed on skis.