由于交通线路对经济的 发展具有举足轻重的作用, 近些年,国家加大了对交通 基础设施的投资,使我国的 交通线路已有较大的增长, 截止1999年,我国的公路里 程已达135.17万公里,其中 高等级公路达1.16万公里, 铁路达5.79万公里,内河航 道达11.65万公里。但是我 国地域广大,环境复杂,自然 灾害频繁,所以要保持交通 运输港站、交通线路等基础 In recent years, the state has increased its investment in transportation infrastructure and made the traffic routes in our country have made great growth. As of 1999, the mileage of our country has reached 135.17 10,000 kilometers, of which 11,600 kilometers of high-grade highways, the railway up to 57,900 km, 116,600 km of inland waterways. However, China’s vast territory, complex environment and frequent natural disasters, so to maintain the transportation port, transport routes and other basic